Tagged: NASA/MIT TESS Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 5:42 pm on January 8, 2020 Permalink | Reply
    Tags: "NASA’s new exoplanet hunter found its first potentially habitable world", , , , , , , NASA/MIT TESS, Planet TOI 700 d   

    From MIT Technology Review: “NASA’s new exoplanet hunter found its first potentially habitable world” 

    MIT Technology Review
    From MIT Technology Review

    Neel V. Patel

    TOI 700 d

    NASA’s Transiting Exoplanet Survey Satellite (TESS) has just found a new potentially habitable exoplanet the size of Earth, located about 100 light-years away. It’s the first potentially habitable exoplanet the telescope has found since it was launched in April 2018.

    NASA/MIT TESS replaced Kepler in search for exoplanets

    It’s called TOI 700 d [science paper https://arxiv.org/abs/2001.00952 ]. It orbits a red dwarf star about 40% less massive than the sun and half as cool. The planet itself is about 1.2 times the size of Earth and orbits the host star every 37 days, receiving close to 86% of the amount of sunlight Earth does.

    Most notably, TOI 700 d is in what’s thought to be its star’s habitable zone, meaning it’s at a distance where temperatures ought to be moderate enough to support liquid water on the surface. This raises hopes TOI 700 d could be amenable to life—even though no one can agree on what it means for a planet to be habitable.

    A set of 20 different simulations meant to model TOI 700 d suggest the planet is rocky and has an atmosphere that helps it retain water, but there’s a chance it might simply be a gaseous mini-Neptune. We won’t know for sure until follow-up observations are made with some sharper instruments, such as the upcoming James Webb Space Telescope, which is planned for launch in March 2021.

    NASA/ESA/CSA Webb Telescope annotated

    TESS finds exoplanets using the tried-and-true technique of looking for objects as they’re transiting in front of their host stars.

    Planet transit. NASA/Ames

    Data from NASA’s Spitzer Space Telescope was also used to get some closer measurements of the planet’s size and orbit.

    NASA/Spitzer Infrared Telescope

    Tess is NASA’s newest exoplanet-hunting space telescope, the successor to the renowned Kepler Space Telescope that was used to find some 2,600 exoplanets.

    NASA/Kepler Telescope, and K2 March 7, 2009 until November 15, 2018

    TESS, able to survey 85% of the night sky (400 times more than what Kepler could monitor), is about to finish its primary two-year mission but has fallen woefully short of expectations. NASA initially thought TESS was going to find more than 20,000 transiting exoplanets, but with only months left it has only identified 1,588 candidates. Even so, the telescope’s mission will almost surely be extended.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    The mission of MIT Technology Review is to equip its audiences with the intelligence to understand a world shaped by technology.

  • richardmitnick 1:33 pm on January 7, 2020 Permalink | Reply
    Tags: "NASA’s TESS Mission Uncovers Its 1st World with Two Stars", , , , , NASA/MIT TESS,   

    From SETI Institute: “NASA’s TESS Mission Uncovers Its 1st World with Two Stars” 

    SETI Logo new
    From SETI Institute

    Jan 6, 2020
    Rebecca McDonald
    Director of Communications
    SETI Institute

    Written by
    Jeanette Kazmierczak
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    TOI 1338 b is silhouetted by its host stars. TESS only detects transits from the larger star. Credit: NASA’s Goddard Space Flight Center/Chris Smith.

    In 2019, when Wolf Cukier finished his junior year at Scarsdale High School in New York, he joined NASA’s Goddard Space Flight Center in Greenbelt, Maryland, as a summer intern. His job was to examine variations in star brightness captured by NASA’s Transiting Exoplanet Survey Satellite (TESS) and uploaded to the Planet Hunters TESS citizen science project.

    NASA/MIT TESS replaced Kepler in search for exoplanets

    “I was looking through the data for everything the volunteers had flagged as an eclipsing binary, a system where two stars circle around each other and from our view eclipse each other every orbit,” Cukier said. “About three days into my internship, I saw a signal from a system called TOI 1338. At first I thought it was a stellar eclipse, but the timing was wrong. It turned out to be a planet.”

    TOI 1338 b, as it is now called, is TESS’s first circumbinary planet, a world orbiting two stars. The discovery was featured in a panel discussion on Monday, Jan. 6, at the 235th American Astronomical Society meeting in Honolulu. A paper, which Cukier co-authored along with scientists from Goddard, San Diego State University, the University of Chicago and other institutions, has been submitted to a scientific journal.

    The TOI 1338 system lies 1,300 light-years away in the constellation Pictor. The two stars orbit each other every 15 days. One is about 10% more massive than our Sun, while the other is cooler, dimmer and only one-third the Sun’s mass.

    TOI 1338 b is the only known planet in the system. It’s around 6.9 times larger than Earth, or between the sizes of Neptune and Saturn. The planet orbits in almost exactly the same plane as the stars, so it experiences regular stellar eclipses.

    TESS has four cameras, which each take a full-frame image of a patch of the sky every 30 minutes for 27 days. Scientists use the observations to generate graphs of how the brightness of stars change over time. When a planet crosses in front of its star from our perspective, an event called a transit, its passage causes a distinct dip in the star’s brightness.

    Planet transit. NASA/Ames

    But planets orbiting two stars are more difficult to detect than those orbiting one. TOI 1338 b’s transits are irregular, between every 93 and 95 days, and vary in depth and duration thanks to the orbital motion of its stars. TESS only sees the transits crossing the larger star; the transits of the smaller star are too faint to detect.

    “These are the types of signals that algorithms really struggle with,” said lead author Veselin Kostov, a research scientist at the SETI Institute and Goddard. “The human eye is extremely good at finding patterns in data, especially non-periodic patterns like those we see in transits from these systems.”

    This explains why Cukier had to visually examine each potential transit. For example, he initially thought TOI 1338 b’s transit was a result of the smaller star in the system passing in front of the larger one — both cause similar dips in brightness. But the timing was wrong for an eclipse.

    After identifying TOI 1338 b, the research team used a software package called eleanor, named after Eleanor Arroway, the central character in Carl Sagan’s novel “Contact,” to confirm the transits were real and not a result of instrumental artifacts.

    “Throughout all of its images, TESS is monitoring millions of stars,” said co-author Adina Feinstein, a graduate student at the University of Chicago. “That’s why our team created eleanor. It’s an accessible way to download, analyze and visualize transit data. We designed it with planets in mind, but other members of the community use it to study stars, asteroids and even galaxies.”

    TOI 1338 had already been studied from the ground by radial velocity surveys, which measure motion along our line of sight. Kostov’s team used this archival data to analyze the system and confirm the planet. Although the planet transits irregularly, its orbit is stable for at least the next 10 million years. The orbit’s angle to us, however, changes enough that the planet transit will cease after November 2023 and resume eight years later.

    NASA’s Kepler and K2 missions previously discovered 12 circumbinary planets in 10 systems, all similar to TOI 1338 b.

    NASA/Kepler Telescope, and K2 March 7, 2009 until November 15, 2018

    Observations of binary systems are biased toward finding larger planets, Kostov said. Transits of smaller bodies don’t have as big an effect on the stars’ brightness. TESS is expected to observe hundreds of thousands of eclipsing binaries during its initial two-year mission, so many more of these circumbinary planets should be waiting for discovery.

    NASA’s Transiting Exoplanet Survey Satellite found its first circumbinary planet, a world orbiting two stars 1,300 light-years away. Watch to learn more about this Saturn-size world called TOI 1338 b.
    Credit: NASA’s Goddard Space Flight Center

    TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center. Additional partners include Northrop Grumman, based in Falls Church, Virginia; NASA’s Ames Research Center in California’s Silicon Valley; the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts; MIT’s Lincoln Laboratory; and the Space Telescope Science Institute in Baltimore. More than a dozen universities, research institutes and observatories worldwide are participants in the mission.

    See the full article here.


    Please help promote STEM in your local schools.

    Stem Education Coalition

    SETI Institute

    About the SETI Institute
    What is life? How does it begin? Are we alone? These are some of the questions we ask in our quest to learn about and share the wonders of the universe. At the SETI Institute we have a passion for discovery and for passing knowledge along as scientific ambassadors.

    The SETI Institute is a 501 (c)(3) nonprofit scientific research institute headquartered in Mountain View, California. We are a key research contractor to NASA and the National Science Foundation (NSF), and we collaborate with industry partners throughout Silicon Valley and beyond.

    Founded in 1984, the SETI Institute employs more than 130 scientists, educators, and administrative staff. Work at the SETI Institute is anchored by three centers: the Carl Sagan Center for the Study of Life in the Universe (research), the Center for Education and the Center for Outreach.

    The SETI Institute welcomes philanthropic support from individuals, private foundations, corporations and other groups to support our education and outreach initiatives, as well as unfunded scientific research and fieldwork.

    A Special Thank You to SETI Institute Partners and Collaborators
    • Campoalto, Chile, NASA Ames Research Center, NASA Headquarters, National Science Foundation, Aerojet Rocketdyne,SRI International

    Frontier Development Lab Partners
    • Breakthrough Prize Foundation, European Space Agency, Google Cloud, IBM, Intel, KBRwyle. Kx Lockheed Martin, NASA Ames Research Center, Nvidia, SpaceResources Luxembourg, XPrize

    In-kind Service Providers
    • Gunderson Dettmer – General legal services, Hello Pilgrim – Website Design and Development Steptoe & Johnson – IP legal services, Danielle Futselaar

    SETI/Allen Telescope Array situated at the Hat Creek Radio Observatory, 290 miles (470 km) northeast of San Francisco, California, USA, Altitude 986 m (3,235 ft)

    SETI Institute – 189 Bernardo Ave., Suite 100
    Mountain View, CA 94043
    Phone 650.961.6633 – Fax 650-961-7099
    Privacy PolicyQuestions and Comments

    Also in the hunt, but not a part of the SETI Institute

    SETI@home, a BOINC project originated in the Space Science Lab at UC Berkeley


    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

  • richardmitnick 12:02 pm on December 31, 2019 Permalink | Reply
    Tags: , , , , , ESA’s Characterising Exoplanet Satellite Cheops, , Future giant ground based optical telescopes, , NASA/MIT TESS   

    From ars technica: “The 2010s: Decade of the exoplanet” 

    Ars Technica
    From ars technica

    John Timmer

    Artist conception of Kepler-186f, the first Earth-size exoplanet found in a star’s “habitable zone.”

    ESO Belgian robotic Trappist National Telescope at Cerro La Silla, Chile

    A size comparison of the planets of the TRAPPIST-1 system, lined up in order of increasing distance from their host star. The planetary surfaces are portrayed with an artist’s impression of their potential surface features, including water, ice, and atmospheres. NASA

    Centauris Alpha Beta Proxima 27, February 2012. Skatebiker

    The last ten years will arguably be seen as the “decade of the exoplanet.” That might seem like an obvious thing to say, given that the discovery of the first exoplanet was honored with a Nobel Prize this year. But that discovery happened back in 1995—so what made the 2010s so pivotal?

    One key event: 2009’s launch of the Kepler planet-hunting probe.

    NASA/Kepler Telescope, and K2 March 7, 2009 until November 15, 2018

    Kepler spawned a completely new scientific discipline, one that has moved from basic discovery—there are exoplanets!—to inferring exoplanetary composition, figuring out exoplanetary atmosphere, and pondering what exoplanets might tell us about prospects for life outside our Solar System.

    To get a sense of how this happened, we talked to someone who was in the field when the decade started: Andrew Szentgyorgyi, currently at the Harvard-Smithsonian Center for Astrophysics, where he’s the principal investigator on the Giant Magellan Telescope’s Large Earth Finder instrument.

    Giant Magellan Telescope, 21 meters, to be at the Carnegie Institution for Science’s Las Campanas Observatory, to be built some 115 km (71 mi) north-northeast of La Serena, Chile, over 2,500 m (8,200 ft) high

    In addition to being famous for having taught your author his “intro to physics” course, Szentgyorgyi was working on a similar instrument when the first exoplanet was discovered.

    Two ways to find a planet

    The Nobel-winning discovery of 51 Pegasi b came via the “radial velocity” method, which relies on the fact that a planet exerts a gravitational influence on its host star, causing the star to accelerate slightly toward the planet.

    Radial Velocity Method-Las Cumbres Observatory

    Radial velocity Image via SuperWasp http http://www.superwasp.org-exoplanets.htm

    Unless the planet’s orbit is oriented so that it’s perpendicular to the line of sight between Earth and the star, some of that acceleration will draw the star either closer to or farther from Earth. This acceleration can be detected via a blue or red shift in the star’s light, respectively.

    The surfaces of stars can expand and contract, which also produces red and blue shifts, but these won’t have the regularity of acceleration produced by an orbital body. But it explains why, back in the 1990s, people studying the surface changes in stars were already building the necessary hardware to study radial velocity.

    “We had a group that was building instruments that I’ve worked with to study the pulsations of stars—astroseismology,” Szentgyorgyi told Ars, “but that turns out to be sort of the same instrumentation you would use” to discern exoplanets.

    He called the discovery of 51 Pegasi b a “seismic event” and said that he and his collaborators began thinking about how to use their instruments “probably when I got the copy of Nature” that the discovery was published in. Because some researchers already had the right equipment, a steady if small flow of exoplanet announcements followed.

    During this time, researchers developed an alternate way to find exoplanets, termed the “transit method.”

    Planet transit. NASA/Ames

    The transit method requires a more limited geometry from an exoplanet’s orbit: the plane has to cause the exoplanet to pass through the line of sight between its host star and Earth. During these transits, the planet will eclipse a small fraction of light from the host star, causing a dip in its brightness. This doesn’t require the specialized equipment needed for radial velocity detections, but it does require a telescope that can detect small brightness differences despite the flicker caused by the light passing through our atmosphere.

    By 2009, transit detections were adding regularly to the growing list of exoplanets.

    The tsunami

    In the first year it was launched, Kepler started finding new planets. Given time and a better understanding of how to use the instrument, the early years of the 2010s saw thousands of new planets cataloged. In 2009, Szentgyorgyi said, “it was still ‘you’re finding handfuls of exoplanetary systems.’ And then with the launch of Kepler, there’s this tsunami of results which has transformed the field.”

    Suddenly, rather than dozens of exoplanets, we knew about thousands.

    The tsunami of Kepler planet discoveries.

    The sheer numbers involved had a profound effect on our understanding of planet formation. Rather than simply having a single example to test our models against—our own Solar System—we suddenly had many systems to examine (containing over 4,000 currently known exoplanets). These include objects that don’t exist in our Solar System, things like hot Jupiters, super-Earths, warm Neptunes, and more. “You found all these crazy things that, you know, don’t make any sense from the context of what we knew about the Solar System,” Szentgyorgyi told Ars.

    It’s one thing to have models of planet formation that say some of these planets can form; it’s quite another to know that hundreds of them actually exist. And, in the case of hot Jupiters, it suggests that many exosolar systems are dynamic, shuffling planets to places where they can’t form and, in some cases, can’t survive indefinitely.

    But Kepler gave us more than new exoplanets; it provided a different kind of data. Radial velocity measurements only tell you how much the star is moving, but that motion could be caused by a relatively small planet with an orbital plane aligned with the line of sight from Earth. Or it could be caused by a massive planet with an orbit that’s highly inclined from that line of sight. Physics dictates that, from our perspective, these will produce the same acceleration of the star. Kepler helped us sort out the differences.

    A massive planet orbiting at a steep angle (left) and a small one orbiting at a shallow one will both produce the same motion of a star relative to Earth.

    “Kepler not only found thousands and thousands of exoplanets, but it found them where we know the geometry,” Szentgyorgyi told Ars. “If you know the geometry—if you know the planet transits—you know your orbital inclination is in the plane you’re looking.” This allows follow-on observations using radial velocity to provide a more definitive mass of the exoplanet. Kepler also gave us the radius of each exoplanet.

    “Once you know the mass and radius, you can infer the density,” Szentgyorgyi said. “There’s a remarkable amount of science you can do with that. It doesn’t seem like a lot, but it’s really huge.”

    Density can tell us if a planet is rocky or watery—or whether it’s likely to have a large atmosphere or a small one. Sometimes, it can be tough to tell two possibilities apart; density consistent with a watery world could also be provided by a rocky core and a large atmosphere. But some combinations are either physically implausible or not consistent with planetary formation models, so knowing the density gives us good insight into the planetary type.

    Beyond Kepler

    Despite NASA’s heroic efforts, which kept Kepler going even after its hardware started to fail, its tsunami of discoveries slowed considerably before the decade was over. By that point, however, it had more than done its job. We had a new catalog of thousands of confirmed exoplanets, along with a new picture of our galaxy.

    For instance, binary star systems are common in the Milky Way; we now know that their complicated gravitational environment isn’t a barrier to planet formation.

    We also know that the most common type of star is the low-mass red dwarf. It was previously possible to think that the star’s low mass would be matched by a low-mass planet-forming disk, preventing the generation of large planets and the generation of large families of smaller planets. Neither turned out to be true.

    “We’ve moved into a mode where we can actually say interesting, global, statistical things about exoplanets,” Szentgyorgyi told Ars. “Most exoplanets are small—they’re sort of Earth to sub-Neptune size. It would seem that probably most of the solar-type stars have exoplanets.” And, perhaps most important, there’s a lot of them. “The ubiquity of exoplanets certainly is a stunner… they’re just everywhere,” Szentgyorgyi added.

    That ubiquity has provided the field with two things. First, it has given scientists the confidence to build new equipment, knowing that there are going to be planets to study. The most prominent piece of gear is NASA’s Transiting Exoplanet Survey Satellite, a space-based telescope designed to perform an all-sky exoplanet survey using methods similar to Kepler’s.

    NASA/MIT TESS replaced Kepler in search for exoplanets

    But other projects are smaller, focused on finding exoplanets closer to Earth. If exoplanets are everywhere, they’re also likely to be orbiting stars that are close enough so we can do detailed studies, including characterizing their atmospheres. One famous success in this area came courtesy of the TRAPPIST telescopes [above], which spotted a system hosting at least seven planets. More data should be coming soon, too; on December 17, the European Space Agency launched the first satellite dedicated to studying known exoplanets.


    With future telescopes and associated hardware similar to what Szentgyorgyi is working on, we should be able to characterize the atmospheres of planets out to about 30 light years from Earth. One catch: this method requires that the planet passes in front of its host star from Earth’s point of view.

    When an exoplanet transits in front of its star, most of the light that reaches Earth comes directly to us from the star. But a small percentage passes through the atmosphere of the exoplanet, allowing it to interact with the gases there. The molecules that make up the atmosphere can absorb light of specific wavelengths—essentially causing them to drop out of the light that makes its way to Earth. Thus, the spectrum of the light that we can see using a telescope can contain the signatures of various gases in the exoplanet’s atmosphere.

    There are some important caveats to this method, though. Since the fraction of light that passes through the exoplanet atmosphere is small compared to that which comes directly to us from the star, we have to image multiple transits for the signal to stand out. And the host star has to have a steady output at the wavelengths we’re examining in order to keep its own variability from swamping the exoplanetary signal. Finally, gases in the exoplanet’s atmosphere are constantly in motion, which can make their signals challenging to interpret. (Clouds can also complicate matters.) Still, the approach has been used successfully on a number of exoplanets now.

    In the air

    Understanding atmospheric composition can tell us critical things about an exoplanet. Much of the news about exoplanet discoveries has been driven by what’s called the “habitable zone.” That zone is defined as the orbital region around a star where the amount of light reaching a planet’s surface is sufficient to keep water liquid. Get too close to the star and there’s enough energy reaching the planet to vaporize the water; get too far away and the energy is insufficient to keep water liquid.

    These limits, however, assume an atmosphere that’s effectively transparent at all wavelengths. As we’ve seen in the Solar System, greenhouse gases can play an outsized role in altering the properties of planets like Venus, Earth, and Mars. At the right distance from a star, greenhouse gases can make the difference between a frozen rock and a Venus-like oven. The presence of clouds can also alter a planet’s temperature and can sometimes be identified by imaging the atmosphere. Finally, the reflectivity of a planet’s surface might also influence its temperature.

    The net result is that we don’t know whether any of the planets in a star’s “habitable zone” are actually habitable. But understanding the atmosphere can give us good probabilities, at least.

    The atmosphere can also open a window into the planet’s chemistry and history. On Venus, for example, the huge levels of carbon dioxide and the presence of sulfur dioxide clouds indicate that the planet has an oxidizing environment and that its atmosphere is dominated by volcanic activity. The composition of the gas giants in the outer Solar System likely reflects the gas that was present in the disk that formed the planets early in the Solar System’s history.

    But the most intriguing prospect is that we could find something like Earth, where biological processes produce both methane and the oxygen that ultimately converts it to carbon dioxide. The presence of both in an atmosphere indicates that some process(es) are constantly producing the gases, maintaining a long-term balance. While some geological phenomena can produce both these chemicals, finding them together in an atmosphere would at least be suggestive of possible life.


    Just the prospect of finding hints of life on other worlds has rapidly transformed the study of exoplanets, since it’s a problem that touches on nearly every area of science. Take the issue of atmospheres and habitability. Even if we understand the composition of a planet’s atmosphere, its temperature won’t just pop out of a simple equation. Distance from the star, type of star, the planet’s rotation, and the circulation of the atmosphere will all play a role in determining conditions. But the climate models that we use to simulate Earth’s atmosphere haven’t been capable of handling anything but the Sun and an Earth-like atmosphere. So extensive work has had to be done to modify them to work with the conditions found elsewhere.

    Similar problems appear everywhere. Geologists and geochemists have to infer likely compositions given little more than a planet’s density and perhaps its atmospheric compositions. Their results need to be combined with atmospheric models to figure out what the surface chemistry of a planet might be. Biologists and biochemists can then take that chemistry and figure out what reactions might be possible there. Meanwhile, the planetary scientists who study our own Solar System can provide insight into how those processes have worked out here.

    “I think it’s part of the Renaissance aspect of exoplanets,” Szentgyorgyi told Ars. “A lot of people now think a lot more broadly, there’s a lot more cross-disciplinary interaction. I find that I’m going to talks about geology, I’m going to talks about the atmospheric chemistry on Titan.”

    The next decade promises incredible progress. A new generation of enormous telescopes is expected to come online, and the James Webb space telescope should devote significant time to imaging exosolar systems.

    NASA/ESA/CSA Webb Telescope annotated

    Other giant 30 meter class telescopes planned

    ESO/E-ELT,39 meter telescope to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).

    TMT-Thirty Meter Telescope, proposed and now approved for Mauna Kea, Hawaii, USA4,207 m (13,802 ft) above sea level, the only giant 30 meter class telescope for the Northern hemisphere


    We’re likely to end up with much more detailed pictures of some intriguing bodies in our galactic neighborhood.

    The data that will flow from new experiments and new devices will be interpreted by scientists who have already transformed their field. That transformation—from proving that exoplanets exist to establishing a vibrant, multidisciplinary discipline—really took place during the 2010s, which is why it deserves the title “decade of exoplanets.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Ars Technica was founded in 1998 when Founder & Editor-in-Chief Ken Fisher announced his plans for starting a publication devoted to technology that would cater to what he called “alpha geeks”: technologists and IT professionals. Ken’s vision was to build a publication with a simple editorial mission: be “technically savvy, up-to-date, and more fun” than what was currently popular in the space. In the ensuing years, with formidable contributions by a unique editorial staff, Ars Technica became a trusted source for technology news, tech policy analysis, breakdowns of the latest scientific advancements, gadget reviews, software, hardware, and nearly everything else found in between layers of silicon.

    Ars Technica innovates by listening to its core readership. Readers have come to demand devotedness to accuracy and integrity, flanked by a willingness to leave each day’s meaningless, click-bait fodder by the wayside. The result is something unique: the unparalleled marriage of breadth and depth in technology journalism. By 2001, Ars Technica was regularly producing news reports, op-eds, and the like, but the company stood out from the competition by regularly providing long thought-pieces and in-depth explainers.

    And thanks to its readership, Ars Technica also accomplished a number of industry leading moves. In 2001, Ars launched a digital subscription service when such things were non-existent for digital media. Ars was also the first IT publication to begin covering the resurgence of Apple, and the first to draw analytical and cultural ties between the world of high technology and gaming. Ars was also first to begin selling its long form content in digitally distributable forms, such as PDFs and eventually eBooks (again, starting in 2001).

  • richardmitnick 6:58 am on December 24, 2019 Permalink | Reply
    Tags: "How 2019’s space missions explored distant worlds", Japan’s Hayabusa2 spacecraft, JAXA’s original Hayabusa spacecraft, , , NASA/MIT TESS, ,   

    From Science News: “How 2019’s space missions explored distant worlds” 

    From Science News

    Maria Temming

    Planets, asteroids and Arrokoth were the focus of new discoveries.

    Japan’s Hayabusa2 spacecraft, whose shadow is visible in this image, took this photo of the asteroid Ryugu in February after briefly touching down on the asteroid’s surface to collect a sample. The spacecraft is now heading back to Earth.
    JAXA, Univ. of Tokyo, Kochi Univ., Rikkyo Univ., Nagoya Univ., Chiba Inst. Of Technology, Meiji Univ., Univ. of Aizu, AIST

    JAXA/Hayabusa 2 Credit: JAXA/Akihiro Ikeshita

    From asteroids to exoplanets, spacecraft are leaving no space rock unturned. While agencies in China, India and Israel made headlines with missions to the moon, here are some other places that space probes scouted in 2019.

    Zoom and enhance

    Touring Pluto in 2015 may have been New Horizons’ main event (SN: 12/26/15, p. 16), but flying by what used to be called Ultima Thule was an awesome encore.

    WORLD LIKE NO OTHER Long out of reach, Pluto came into focus in 2015 with the NASA/Mew Horizons mission.

    Arrokoth appears as a ruddy deformed snowman in this composite image acquired by NASA’s New Horizons spacecraft as it sped past on January 1, 2019. NASA gave Ultima Thule a new official name, Arrokoth.
    NASA, Johns Hopkins University Applied Physics Laboratory, Southwest Research Institute, Roman Tkachenko

    I spy exoplanets

    NASA’s Transiting Exoplanet Survey Satellite, or TESS, racked up eight exoplanet finds in its first few months of observation (SN: 2/2/19, p. 12).

    NASA/MIT TESS replaced Kepler in search for exoplanets

    That initial cache included some weirdos, such as a planet that is about as dense as pure water and a “lava world” known as LHS 3844b that sizzles at about 540° Celsius. TESS has since discovered a new type of exoplanet called an ultrahot Neptune, which appears to be a fluffy gas giant in the process of stripping down to its rocky core (SN: 8/31/19, p. 11).

    Among the exoplanets discovered by NASA’s Transiting Exoplanet Survey Satellite, TESS, is LHS 3844b (illustrated), a “lava world” slightly bigger than Earth.TESS/NASA and MIT

    Asteroids to go

    The Japan Aerospace Exploration Agency’s Hayabusa2 is expected to become the second spacecraft ever to bring a bit of asteroid back to Earth, after the original Hayabusa probe returned with a souvenir from the asteroid Itokawa in 2010.

    JAXA’s original Hayabusa spacecraft

    Hayabusa2 touched down on the asteroid Ryugu in February to fetch a sample from the asteroid’s surface (SN Online: 2/22/19). Then, to get a deeper sample, Hayabusa2 fired a copper projectile at Ryugu to punch a crater into the asteroid (SN Online: 4/5/19). The probe then ducked down to snag some rubble excavated from the interior (SN: 8/17/19, p. 14). Scientists won’t know exactly how much of Ryugu was collected until Hayabusa2, which started its journey home on November 13, arrives at Earth in late 2020.

    Another sample-return mission, NASA’s OSIRIS-REx, is still orbiting its asteroid.

    NASA OSIRIS-REx Spacecraft

    When the spacecraft first arrived at Bennu in December 2018, observations unveiled a rugged surface littered with boulders — bad news for a probe designed to navigate more beachlike terrain (SN: 4/13/19, p. 10).

    This mosaic image of asteroid Bennu is composed of 12 PolyCam images collected on Dec. 2 by the OSIRIS-REx spacecraft from a range of 15 miles (24 km). The image was obtained at a 50° phase angle between the spacecraft, asteroid and the Sun, and in it, Bennu spans approximately 1,500 pixels in the camera’s field of view.

    Using OSIRIS-REx’s detailed mapping of Bennu from orbit, NASA selected a site for sample collection in the asteroid’s northern hemisphere (SN Online: 12/12/19). Bits of Bennu, to be returned in 2023, may reveal whether a similar asteroid could have delivered to early Earth a molecular starter pack for life (SN: 1/19/19, p. 20).

    The space probe zipped by this Kuiper Belt object, now called Arrokoth, on New Year’s Day (SN Online: 12/30/18).

    Kuiper Belt. Minor Planet Center

    Scientists were on the edge of their seats as the probe snapped pictures and sent higher- and higher-resolution images over several weeks, revealing the visage of Arrokoth to look like an elongated blob, then a snowman and finally a pair of lumpy pancakes (SN: 3/16/19, p. 15). Uncovering the origins of Arrokoth’s awkward shape may lend insight into the early stages of planet formation (SN: 4/13/19, p. 11).

    Meanwhile, on Mars

    NASA’s Mars InSight mission may have made the first recording of a Marsquake. InSight’s seismometer is covered by the domed shield shown here.JPL-Caltech/NASA

    NASA/Mars InSight Lander

    InSight arrived on the Red Planet in November 2018, and the rookie lander may have already captured the first recording of a Marsquake (SN Online: 4/23/19). Unlike tremors on Earth, underground rumblings on Mars are thought to result from the planet contracting as it cools. Studying such seismic signals could help scientists better understand the structure of Mars’ deep interior.

    While InSight had its ear to the ground, the veteran Curiosity rover was measuring the consistency of a Martian mountain (SN Online: 1/31/19).

    NASA/Mars Curiosity Rover

    As Curiosity scaled Mount Sharp, accelerometer readings indicated surprisingly loose rock beneath the rover’s wheels — suggesting that winds formed the mountain by sweeping sediment into a giant pile.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 12:56 pm on December 9, 2019 Permalink | Reply
    Tags: "Mass-ive Implications for Exoplanetary Atmospheres", , , , , , Measuring planetary masses to some degree of precision., NASA/MIT TESS, The Use of Transmission Spectra   

    From AAS NOVA: “Mass-ive Implications for Exoplanetary Atmospheres” 


    From AAS NOVA

    9 December 2019
    Tarini Konchady

    Artist’s impression of an extrasolar planet system. [R. Hurt (IPAC)/NASA/JPL-Caltech]

    One of the goals of the Transiting Exoplanet Survey Satellite (TESS) is to identify exoplanets whose atmospheres can be characterized by other telescopes.

    NASA/MIT TESS replaced Kepler in search for exoplanets

    Part of this process entails measuring planetary masses to some degree of precision. So just how well do we need to know an exoplanet’s mass to understand its atmosphere?

    The Use of Transmission Spectra

    One way to study the atmosphere of an exoplanet is to observe the light from its host star that passes through the planet’s atmosphere. Comparing the resulting spectrum — called a transmission spectrum — with the spectrum of the host star alone can tell us about what’s in the planet’s atmosphere.

    A planet’s mass plays an important role in how far its atmosphere extends. This has prompted studies on whether a planet’s mass could be inferred from its transmission spectrum alone. In some cases, this approach works. But in other cases, the transmission spectra of very different planets can appear to be alike.

    The precision of exoplanet mass measurements versus their most likely mass. The seven planets used in this study are highlighted. [Adapted from Batalha et al. 2019]

    So should we know the mass of a planet before trying to characterize its atmosphere? If so, how well? And how do these answers change for different types of planets? Natasha Batalha (University of California, Santa Cruz) and collaborators attempt to tackle these questions with simulated James Webb Space Telescope (JWST) transmission spectra.

    Seven Special Planets

    For their study, Batalha and collaborators chose seven known planets that span the gamut of exoplanets we’ve observed. Their sample included three hot Jupiters (WASP-17b, HAT-P-1b, WASP-12b), three Neptune-like planets (HAT-P-26 b, GJ 436b, GJ 1214b), and one Earth-like planet (TRAPPIST-1e).

    To simulate transmission spectra, the authors started with models that are consistent with Hubble spectroscopy of their chosen planets. They then used these models to simulate the analogous JWST spectra.

    Aside from mass, the sample planets also varied in composition. Their host stars are also different, meaning that in real life the JWST would have to adopt different observing strategies to get quality transmission spectra.

    The accuracy with which different atmospheric properties are recovered from the simulated transmission spectra. From top left, clockwise: temperature, metallicity (the abundance of elements that are not hydrogen or helium), radius, and mass. The shaded regions correspond to mass being known and the unfilled regions correspond to mass not being known. The colors of the curves indicate different planets. [Batalha et al. 2019]

    A Matter of Caution

    To test what role mass played in the usefulness of transmission spectra, the authors attempted to measure atmospheric properties from their modeled spectra. They tried different precisions on mass (how far off the assumed mass could be from the true mass) as well as not knowing a planet’s mass at all.

    The authors found that transmission spectra alone could not reliably characterize a planet’s atmosphere. Hot Jupiters required the loosest mass constraints to infer atmospheric properties, though cloud cover — such as in the case of WASP-12b — could make that untrue. For the other Neptunes and the Earth-like planet, mass had to be known with at least a 50% precision to get accurate atmospheric properties.

    A recurring theme was that a mass measurement is necessary to distinguish one planet from others with similar transmission spectra. To this end, the authors recommend that any planets selected for atmospheric characterization have their mass known to at least 50% precision.

    One of TESS’s goals is to measure the mass of fifty Earth-sized planets, and Batalha and collaborators have set a benchmark for those measurements. This sort of groundwork is critical to exoplanet science and should contribute to great results not too long from now!


    “The Precision of Mass Measurements Required for Robust Atmospheric Characterization of Transiting Exoplanets,” Natasha E. Batalha et al 2019 ApJL 885 L25.

    See the full article here .
    See also from UCSC “From UC Santa Cruz and Carnegie Institution for Science: “Composition of gas giant planets not determined by host star, study finds”


    Please help promote STEM in your local schools.

    Stem Education Coalition


    AAS Mission and Vision Statement

    The mission of the American Astronomical Society is to enhance and share humanity’s scientific understanding of the Universe.

    The Society, through its publications, disseminates and archives the results of astronomical research. The Society also communicates and explains our understanding of the universe to the public.
    The Society facilitates and strengthens the interactions among members through professional meetings and other means. The Society supports member divisions representing specialized research and astronomical interests.
    The Society represents the goals of its community of members to the nation and the world. The Society also works with other scientific and educational societies to promote the advancement of science.
    The Society, through its members, trains, mentors and supports the next generation of astronomers. The Society supports and promotes increased participation of historically underrepresented groups in astronomy.
    The Society assists its members to develop their skills in the fields of education and public outreach at all levels. The Society promotes broad interest in astronomy, which enhances science literacy and leads many to careers in science and engineering.

    Adopted June 7, 2009

  • richardmitnick 4:54 pm on December 3, 2019 Permalink | Reply
    Tags: "NASA’s Exoplanet-Hunting Mission Catches a Natural Comet Outburst in Unprecedented Detail", , , , , NASA/MIT TESS   

    From NASA/MIT TESS: “NASA’s Exoplanet-Hunting Mission Catches a Natural Comet Outburst in Unprecedented Detail” 

    NASA/MIT TESS replaced Kepler in search for exoplanets

    NASA image

    Dec. 3, 2019

    Claire Andreoli
    NASA’s Goddard Space Flight Center
    301-286 -1940

    Matthew Wright
    University of Maryland, College Park

    Using data from NASA’s Transiting Exoplanet Survey Satellite (TESS), astronomers at the University of Maryland (UMD), in College Park, Maryland, have captured a clear start-to-finish image sequence of an explosive emission of dust, ice and gases during the close approach of comet 46P/Wirtanen in late 2018. This is the most complete and detailed observation to date of the formation and dissipation of a naturally-occurring comet outburst. The team members reported their results in the November 22 issue of The Astrophysical Journal Letters.

    This animation shows an explosive outburst of dust, ice and gases from comet 46P/Wirtanen that occurred on September 26, 2018 and dissipated over the next 20 days. The images, from NASA’s TESS spacecraft, were taken every three hours during the first three days of the outburst. Credits: Farnham et al./NASA

    “TESS spends nearly a month at a time imaging one portion of the sky. With no day or night breaks and no atmospheric interference, we have a very uniform, long-duration set of observations,” said Tony Farnham, a research scientist in the UMD Department of Astronomy and the lead author of the research paper. “As comets orbit the Sun, they can pass through TESS’ field of view. Wirtanen was a high priority for us because of its close approach in late 2018, so we decided to use its appearance in the TESS images as a test case to see what we could get out of it. We did so and were very surprised!”

    “While TESS is a powerhouse for discovering planets orbiting nearby, bright stars, its observing strategy enables so much exciting additional science,” said TESS project scientist Padi Boyd of NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Since the TESS data are rapidly made public through NASA’s Mikulski Archive for Space Telescopes (MAST), it’s exciting to see scientists identifying which data are of interest to them, and then doing all kinds of additional serendipitous science beyond exoplanets.”

    Normal comet activity is driven by sunlight vaporizing the ices near the surface of the nucleus, and the outflowing gases drag dust off the nucleus to form the coma. However, many comets are known to experience occasional spontaneous outbursts that can significantly, but temporarily increase the comet’s activity. It is not currently known what causes outbursts, but they are related to the conditions on the comet’s surface. A number of potential trigger mechanisms have been proposed, including a thermal event, in which a heat wave penetrates into a pocket of highly volatile ices, causing the ice to rapidly vaporize and produce an explosion of activity, and a mechanical event, where a cliff collapses, exposing fresh ice to direct sunlight. Thus, studies of the outburst behavior, especially in the early brightening stages that are difficult to capture, can help us understand the physical and thermal properties of the comet.

    Although Wirtanen came closest to Earth on December 16, 2018, the outburst occurred earlier in its approach, beginning on September 26, 2018. The initial brightening of the outburst occurred in two distinct phases, with an hour-long flash followed by a more gradual second stage that continued to grow brighter for another 8 hours. This second stage was likely caused by the gradual spreading of comet dust from the outburst, which causes the dust cloud to reflect more sunlight overall. After reaching peak brightness, the comet faded gradually over a period of more than two weeks. Because TESS takes detailed, composite images every 30 minutes, the team was able to view each phase in exquisite detail.

    “With 20 days’ worth of very frequent images, we were able to assess changes in brightness very easily. That’s what TESS was designed for, to perform its primary job as an exoplanet surveyor,” Farnham said. “We can’t predict when comet outbursts will happen. But even if we somehow had the opportunity to schedule these observations, we couldn’t have done any better in terms of timing. The outburst happened mere days after the observations started.”

    The team has generated a rough estimate of how much material may have been ejected in the outburst, about one million kilograms (2.2 million pounds), which could have left a crater on the comet of around 20 meters (about 65 feet) across. Further analysis of the estimated particle sizes in the dust tail may help improve this estimate. Observing more comets will also help to determine whether multi-stage brightening is rare or commonplace in comet outbursts.

    TESS has also detected for the first time Wirtanen’s dust trail. Unlike a comet’s tail—the spray of gas and fine dust that follows behind a comet, growing as it approaches the sun—a comet’s trail is a field of larger debris that traces the comet’s orbital path as it travels around the sun. Unlike a tail, which changes direction as it is blown by the solar wind, the orientation of the trail stays more or less constant over time.

    “The trail more closely follows the orbit of the comet, while the tail is offset from it, as it gets pushed around by the sun’s radiation pressure. What’s significant about the trail is that it contains the largest material,” said Michael Kelley, an associate research scientist in the UMD Department of Astronomy and a co-author of the research paper. “Tail dust is very fine, a lot like smoke. But trail dust is much larger—more like sand and pebbles. We think comets lose most of their mass through their dust trails. When the Earth runs into a comet’s dust trail, we get meteor showers.”

    While the current study describes initial results, Farnham, Kelley and their colleagues look forward to further analyses of Wirtanen, as well as other comets in TESS’ field of view. “We also don’t know what causes natural outbursts and that’s ultimately what we want to find,” Farnham said. “There are at least four other comets in the same area of the sky where TESS made these observations, with a total of about 50 comets expected in the first two years’ worth of TESS data. There’s a lot that can come of these data.”

    For an image, refer to: https://www.nasa.gov/feature/goddard/2019/tess-comet-outburst

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Transiting Exoplanet Survey Satellite (TESS) will discover thousands of exoplanets in orbit around the brightest dwarf stars in the sky. In a two-year survey of the solar neighborhood, TESS will monitor the brightness of stars for periodic drops caused by planet transits. The TESS mission is finding planets ranging from small, rocky worlds to giant planets, showcasing the diversity of planets in the galaxy.

    Astronomers predict that TESS will discover dozens of Earth-sized planets and up to 500 planets less than twice the size of Earth. In addition to Earth-sized planets, TESS is expected to find some 20,000 exoplanets in its two-year prime mission. TESS will find upwards of 17,000 planets larger than Neptune.

    TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Dr. George Ricker of MIT’s Kavli Institute for Astrophysics and Space Research serves as principal investigator for the mission. Additional partners include Northrop Grumman, based in Falls Church, Virginia; NASA’s Ames Research Center in California’s Silicon Valley; the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts; MIT’s Lincoln Laboratory in Lexington, Massachusetts; and the Space Telescope Science Institute in Baltimore. More than a dozen universities, research institutes and observatories worldwide are participants in the mission.

    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs. NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

  • richardmitnick 12:49 pm on November 14, 2019 Permalink | Reply
    Tags: , , , , Digital tracking, In the case of Planet Nine detecting its transit would be impossible because it wouldn't pass between TESS and the Sun., NASA/MIT TESS, , The search for Planet 9   

    From Science Alert: “TESS Data May Already Hold a Clue to The Mysterious Planet Nine” 


    From Science Alert

    14 NOV 2019

    Artist’s impression of Planet Nine. (nagualdesign/Tom Ruen/ESO/Wikimedia Commons)

    There seems to be something large lurking in the far reaches of the Solar System, messing with the orbits of some of the Kuper Belt rocks out past Neptune. Some astronomers believe it’s a planet, about five times the mass of Earth. They call it Planet Nine.

    But finding this potential lurker is not so simple. From here, it would appear extremely small and faint, and we don’t even know where in the sky we should be looking. Astronomers are searching (and finding some other really neat stuff in the process), but it’s slow and painstaking work.

    According to a new paper [ Research Notes of the AAS], though, there could be another way: NASA’s Transiting Exoplanet Survey Satellite (TESS). And it’s possible the planet has already been observed, and is hidden away in the TESS data.

    NASA/MIT TESS replaced Kepler in search for exoplanets

    You may be thinking “duh, it’s a planet-hunting telescope”, but looking for planets that are very far away, and looking for planets that are relatively close are two different things.

    TESS looks for exoplanets using the transit method.

    Planet transit. NASA/Ames

    It stares at sections of the sky for long durations, looking for faint, regular dips in starlight caused by planets orbiting between us and the star (what is known as a transit).

    In the case of Planet Nine, detecting its transit would be impossible, because it wouldn’t pass between TESS and the Sun.

    And a single exposure wouldn’t reveal an object as faint as Planet Nine. However, the way TESS stares at sections of the sky for long durations could be combined with an astronomy technique called digital tracking.

    In order to reveal transit dips, TESS takes a lot of photos of one field of view. If you stack these images, faint objects can become much brighter, revealing objects that would otherwise be hidden.

    Because Planet Nine is a moving object, just stacking the images wouldn’t necessarily reveal the planet. This is where you have to do a bit of guesswork to calculate an estimated orbit of the object, and sort-of shift the exposures to centre on your estimated position – and stack the images then.

    “To discover new objects, with unknown trajectories,” the researchers wrote in their paper, “we can try all possible orbits!”

    Just feed your images and orbit and parallax corrections (TESS has a highly elliptical orbit around Earth, so the line-of-sight gets displaced as it moves) into a software program and wait for the results.

    It sounds like a scattershot approach, but it might actually work. For example, digital tracking with the Hubble Space Telescope has been used to discover several objects out past Neptune.

    The next question is whether TESS is powerful enough to detect the planet. But there’s a way to test this too.

    Models have suggested Planet Nine has an apparent magnitude – that is, brightness as seen from Earth – between 19 and 24. There are some known orbiting trans-Neptunian objects that have apparent magnitudes within this range – namely, Sedna (20.5 to 20.8), 2015 BP519 (21.5) and 2015 BM518 (21.6).

    (Holman et al., Research Notes of the AAS, 2019)

    So, the team used digital tracking to resolve each of these three objects… and all three showed up, clear as a really fuzzy low-resolution crystal. But still identifiable. You can see them in the image above: From left, that’s Sedna, 2015 BP519 and 2015 BP518. The images have been shown in negative to make the objects easier to see.

    Hypothetically, TESS should be able to see any object at around those magnitudes. Which means, the researchers said, that it should also be able to see Planet Nine. It may even already be there in the data – we just haven’t found it yet.

    You’d have to test for all possible orbits, which could require a lot of computing. So… Anyone got a spare supercomputer?

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 11:03 am on November 7, 2019 Permalink | Reply
    Tags: "A Southern Sky Extravaganza From TESS", , , , , , NASA/MIT TESS   

    From Many Worlds: “A Southern Sky Extravaganza From TESS” 

    NASA NExSS bloc


    Many Words icon

    From Many Worlds

    November 7, 2019
    Marc Kaufman

    NASA/MIT TESS replaced Kepler in search for exoplanets

    Candidate exoplanets as seen by TESS in a southern sky mosaic from 13 observing sectors. (NASA/MIT/TESS)

    NASA’s Transiting Exoplanet Survey Satellite (TESS) has finished its one year full-sky observation of Southern sky and has found hundreds of candidate exoplanets and 29 confirmed planets.

    TESS searches with the Planet Transit method, the same method used so well and for so long by Kepler.

    NASA/Kepler Telescope, and K2 March 7, 2009 until November 15, 2018

    Planet transit. NASA/Ames


    It is now maneuvering its array of wide-field telescopes and cameras to focus on the northern sky to do the same kind of exploration.

    At this turning point, NASA and the Massachusetts Institute of Technology — which played a major role in designing and now operating the mission — have put together mosaic images from the first year’s observations, and they are quite something.

    Constructed from 208 TESS images taken during the mission’s first year of science operations, these images are a unique space-based look at the entire Southern sky — including the Milky Way seen edgewise, the Large and Small Magellenic galaxies, and other large stars already known to have exoplanets.

    “Analysis of TESS data focuses on individual stars and planets one at a time, but I wanted to step back and highlight everything at once, really emphasizing the spectacular view TESS gives us of the entire sky,” said Ethan Kruse, a NASA Postdoctoral Program Fellow who assembled the mosaic at NASA’s Goddard Space Flight Center.

    Overlaying the figures of selected constellations helps clarify the scale of the TESS southern mosaic. TESS has discovered 29 exoplanets, or worlds beyond our solar system, and more than 1,000 candidate planets astronomers are now investigating. NASA/MIT/TESS

    The mission is designed to vastly increase the number of known exoplanets, which are now theorized to orbit all — or most — stars in the sky.

    TESS searches for the nearest and brightest main sequence stars hosting transiting exoplanets, which are the most favorable targets for detailed investigations.

    While previous sky surveys with ground-based telescopes have mainly detected giant exoplanets, TESS will find many small planets around the nearest stars in the sky. The mission will also provide prime targets for further characterization by the James Webb Space Telescope, as well as other large ground-based and space-based telescopes of the future.

    The TESS observatory uses an array of wide-field cameras to perform a survey of 85% of the sky. With the satellite observatory, it is possible to study the mass, size, density and orbit of a large cohort of small planets, including a sample of rocky planets in the habitable zones of their host stars.

    Using the known planet size, orbit and mass, TESS and ground-based follow-up will be able to determine the planets’ compositions. This will reveal whether the planets are rocky (like Earth), gas giants (like Jupiter) or something even more unusual. Additional follow-up with ground- and space-based observatories , will also allow astronomers to study the atmospheres of many of these planets.

    Here is a NASA video describing the images further, zooming in more closely on some particularly interesting features.

    Credits: NASA’s Goddard Space Flight Center Francis Reddy (University of Maryland College Park): Lead Science Writer Claire Andreoli (NASA/GSFC): Public Affairs Officer Scott Wiessinger (USRA): Lead Producer Scott Wiessinger (USRA): Editor Barb Mattson (University of Maryland College Park): Narrator Ethan Kruse (USRA): Visualizer.

    TESS is designed to survey 200,000 of the brightest stars nearest to our sun. Of the thousands of planet candidates to be identified, approximately 300 are expected to be Earth-sized and super-Earth-sized exoplanets, which are worlds no larger than twice the size of Earth.

    TESS is searching for stars 30 to 100 times brighter than those the pioneering Kepler Space Telescope mission and K2 follow-up surveyed from 2009 to 2018. TESS will cover a sky area 400 times larger than that monitored by Kepler, which intentionally stared at a small section of the sky to make it’s census.

    The satellite was launched on April 18, 2018 aboard a SpaceX Falcon 9 rocket. It’s primary mission is to observe for two years, but these missions often last considerably longer.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    About Many Worlds
    There are many worlds out there waiting to fire your imagination.

    Marc Kaufman is an experienced journalist, having spent three decades at The Washington Post and The Philadelphia Inquirer, and is the author of two books on searching for life and planetary habitability. While the “Many Worlds” column is supported by the Lunar Planetary Institute/USRA and informed by NASA’s NExSS initiative, any opinions expressed are the author’s alone.

    This site is for everyone interested in the burgeoning field of exoplanet detection and research, from the general public to scientists in the field. It will present columns, news stories and in-depth features, as well as the work of guest writers.

    About NExSS

    The Nexus for Exoplanet System Science (NExSS) is a NASA research coordination network dedicated to the study of planetary habitability. The goals of NExSS are to investigate the diversity of exoplanets and to learn how their history, geology, and climate interact to create the conditions for life. NExSS investigators also strive to put planets into an architectural context — as solar systems built over the eons through dynamical processes and sculpted by stars. Based on our understanding of our own solar system and habitable planet Earth, researchers in the network aim to identify where habitable niches are most likely to occur, which planets are most likely to be habitable. Leveraging current NASA investments in research and missions, NExSS will accelerate the discovery and characterization of other potentially life-bearing worlds in the galaxy, using a systems science approach.
    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs. NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

  • richardmitnick 12:55 pm on November 4, 2019 Permalink | Reply
    Tags: , , NASA/MIT TESS, Search for Extraterrestrial Intelligence,   

    From Breakthrough Listen Project via EarthSky: “Breakthrough Listen and TESS team up for SETI” 

    From Breakthrough Listen Project




    November 3, 2019
    Paul Scott Anderson

    Will we ever hear from an alien civilization? Will we hear from one in our lifetimes? Now 2 powerhouses in the world of astronomy have teamed up to optimize the chances of a successful search for extraterrestrial intelligence.

    Image via Breakthrough Listen/Danielle Futselaar/SETI (Search for Extraterrestrial Intelligence) Institute.

    In recent decades, missions to planets and moons in our solar system have been alert for signs of microbial life. Astronomers have found thousands of exoplanets, or worlds orbiting distant suns. There’ve been the traditional searches for intelligent radio signals (SETI), now including searches for light signals (optical SETI). Scientists now speak of technosignatures – signs of advanced technologies – as distinct from biosignatures. Late last month, two major programs announced they’re joining forces in the search for intelligent life elsewhere in our galaxy. Breakthrough Listen, part of Breakthrough Initiatives, has announced it will collaborate with NASA’s Transiting Exoplanet Survey Satellite (TESS) mission.

    NASA/MIT TESS replaced Kepler in search for exoplanets

    Breakthrough Listen has $100 million in funding and is using thousands of hours of dedicated telescope time on state-of-the-art earthly facilities – targeting a million nearby stars and the centers of 100 galaxies – in its search for technosignatures. TESS, meanwhile, uses a novel highly-elliptical orbit around Earth (at its farthest from us, it’s as far as the moon) in its task of seeking – and finding – new exoplanets, including smaller, rocky worlds like Earth.

    The new initiative was announced at the International Astronautical Congress (IAC) in Washington, D.C., on October 23, 2019. It’ll be led by TESS Deputy Science Director Sara Seager, S. Pete Worden, Executive Director of Breakthrough Initiatives and Andrew Siemion, leader of the Breakthrough Listen science team.

    The collaboration will allow Breakthrough Listen to focus on more specific targets, rocky planets like Earth that may be habitable. Using data from TESS, it is estimated that over 1,000 new “objects of interest” will be added to Breakthrough Listen’s target list. The project will use a wide range of telescopes, including Green Bank, Parkes Telescopes, MeerKAT2, Automated Planet Finder, VERITAS4, NenuFAR, FAST5, Murchison Widefield Array, LOFAR stations in Ireland and Sweden, Jodrell Bank Observatory, e-MERLIN6, Keck Observatory, Sardinia Radio Telescope and Allen Telescope Array7. Worden said:

    “It’s exciting that the world’s most powerful SETI search, with our partner facilities across the globe, will be collaborating with the TESS team and our most capable planet-hunting machine. We’re looking forward to working together as we try to answer one of the most profound questions about our place in the Universe: Are we alone?”

    TESS is the planet-hunting successor to the Kepler Space Telescope.

    NASA/Kepler Telescope, and K2 March 7, 2009 until November 15, 2018

    Like Kepler, it finds planets by detecting their transits in front of their stars.

    Planet transit. NASA/Ames

    While Kepler focused on distant stars in certain patches of the sky, TESS looks at stars much closer to us, over about 85% of the sky – 400 times more than Kepler – with a prime focus on rocky worlds similar to Earth in size and mass. TESS was launched in April 2018, and has four wide-field cameras, each monitoring a region of sky 24 degrees across (about the width of your hand held at arm’s length). Light curves – how the brightness of stars changes over time – for 20,000 stars are measured every two minutes, and the brightness of every pixel in the cameras is recorded every 30 minutes.

    Over 4,000 exoplanets have been confirmed so far in the past three decades, with many of those coming from Kepler. But TESS is now already quickly adding to that list, and is predicted to find at least 10,000 new exoplanets. Overall, scientists now estimate there are billions of planets in our galaxy alone!

    TESS has a unique advantage in working together with Breakthrough Listen. All the planetary systems it discovers will be edge-on as viewed from Earth. The majority of radio signal leakage on Earth – about 70% – comes from the plane of Earth’s orbit. If an alien civilization had transmitters emitting radio signals in a similar manner, the best chance of detecting them is to view the planetary systems edge-on.

    This, of course, has only to do with radio signals. As many scientists now suggest, there are other possibilities for detecting signs of an advanced alien civilization. If such a civilization was much further ahead technologically than us, it might not use radio at all anymore. Both Breakthrough Listen and TESS are capable of finding other kinds of anomalies as well, such as megastructures in orbit around a planet or star, perhaps resembling a Dyson sphere.

    Artist’s concept of a Dyson sphere, a hypothetical construction around a star to harness the star’s energy. This is one type of technosignature that could be detected by the new Breakthrough Listen/TESS project. Image via SentientDevelopments.com.

    Boyajian’s Star – aka Tabby’s Star – is a good example of a star exhibiting weird, potentially alien-related behavior, as Siemion noted:

    “The discovery by the Kepler spacecraft of Boyajian’s Star, an object with wild, and apparently random, variations in its light curve, sparked great excitement and a range of possible explanations, of which megastructures were just one.

    Theories about Tabby’s Star have ranged from comets to alien megastructures. Could the explanation really be an evaporating exomoon? Image via NASA/JPL-Caltech/Sky & Telescope.

    Follow-up observations have suggested that dust particles in orbit around the star are responsible for the dimming, but studies of anomalies like this are expanding our knowledge of astrophysics, as well as casting a wider net in the search for technosignatures.”

    For those of us hoping to find evidence of intelligent alien life, this new collaboration is exciting. It will help to better refine search efforts as we learn more about which planetary systems would be the best to focus on instead of the more random kinds of searches done in the past. TESS, and other future planet-hunting telescopes, will be invaluable in determining which exoplanets in our galaxy are the most likely to be habitable, allowing Breakthrough Listen and other SETI-type searches to focus more on such worlds as possible homes for alien intelligence. In Seager’s words:

    “We are very enthusiastic about joining the Breakthrough Listen SETI search. Out of all the exoplanet endeavors only SETI holds the promise for identifying signs of intelligent life.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition


    Breakthrough Listen is the largest ever scientific research program aimed at finding evidence of civilizations beyond Earth. The scope and power of the search are on an unprecedented scale:

    The program includes a survey of the 1,000,000 closest stars to Earth. It scans the center of our galaxy and the entire galactic plane. Beyond the Milky Way, it listens for messages from the 100 closest galaxies to ours.

    The instruments used are among the world’s most powerful. They are 50 times more sensitive than existing telescopes dedicated to the search for intelligence.

    These are among the astronomical resources imvolved with Breakthrough Listen

    CSIRO/Parkes Observatory, located 20 kilometres north of the town of Parkes, New South Wales, Australia

    UC Observatories Lick Autmated Planet Finder, fully robotic 2.4-meter optical telescope at Lick Observatory, situated on the summit of Mount Hamilton, east of San Jose, California, USA

    GBO radio telescope, Green Bank, West Virginia, USA

    SKA SARAO Meerkat telescope(s), 90 km outside the small Northern Cape town of Carnarvon, SA

    CfA/VERITAS, a major ground-based gamma-ray observatory with an array of four 12m optical reflectors for gamma-ray astronomy in the GeV – TeV energy range. Located at Fred Lawrence Whipple Observatory,Mount Hopkins, Arizona, US in AZ, USA, Altitude 2,606 m (8,550 ft)

    French NenuFAR Radio telescope

    SKA Murchison Widefield Array, Boolardy station in outback Western Australia, at the Murchison Radio-astronomy Observatory (MRO)

    SKA LOFAR core (“superterp”) near Exloo, Netherlands

    LOFAR Sweden Radio Telescope

    Jodrell Bank Lovell Telescope

    SETI/Allen Telescope Array situated at the Hat Creek Radio Observatory, 290 miles (470 km) northeast of San Francisco, California, USA, Altitude 986 m (3,235 ft)

    The radio surveys cover 10 times more of the sky than previous programs. They also cover at least 5 times more of the radio spectrum – and do it 100 times faster. They are sensitive enough to hear a common aircraft radar transmitting to us from any of the 1000 nearest stars.

    We are also carrying out the deepest and broadest ever search for optical laser transmissions. These spectroscopic searches are 1000 times more effective at finding laser signals than ordinary visible light surveys. They could detect a 100 watt laser (the energy of a normal household bulb) from 25 trillion miles away.

    Listen combines these instruments with innovative software and data analysis techniques.

    The initiative will span 10 years and commit a total of $100,000,000.

  • richardmitnick 3:02 pm on October 29, 2019 Permalink | Reply
    Tags: "TESS reveals an improbable planet", , , , , NASA/MIT TESS,   

    From phys.org: “TESS reveals an improbable planet” 

    From phys.org

    October 29, 2019
    Instituto de Astrofísica e Ciências do Espaço

    Credit: Instituto de Astrofísica e Ciências do Espaço

    Using asteroseismology, a team led by an Instituto de Astrofísica e Ciências do Espaço (IA) researcher studied two red-giant stars known to have exoplanets, and around one of them, found a seemingly improbable planet.

    The team studied the red-giant stars HD 212771 and HD 203949. These are the first detections of oscillations in previously known exoplanet-host stars by TESS. The result was published today in an article in The Astrophysical Journal.

    Tiago Campante (IA & Faculdade de Ciências da Universidade do Porto) says, “TESS observations are precise enough to allow measuring the gentle pulsations at the surfaces of stars. These two fairly evolved stars also host planets, providing the ideal testbed for studies of the evolution of planetary systems.”

    Having determined the physical properties of both stars, such as their mass, size and age, through asteroseismology, the authors then focused their attention on the evolutionary state of HD 203949. Their aim was to understand how its planet could have avoided engulfment, since the envelope of the star would have expanded well beyond the current planetary orbit during the red-giant phase of evolution.

    Co-author Vardan Adibekyan (IA & Universidade do Porto) says, “This study is a perfect demonstration of how stellar and exoplanetary astrophysics are linked together. Stellar analysis seems to suggest that the star is too evolved to still host a planet at such a short orbital distance, while from the exoplanet analysis, we know that the planet is there.”

    By performing extensive numerical simulations, the team thinks that star-planet tides might have brought the planet inward from its original, wider orbit, placing it where we see it today. Adibekyan says, “The solution to this scientific dilemma is hidden in the simple fact that stars and their planets not only form, but also evolve together. In this particular case, the planet managed to avoid engulfment.”

    In the past decade, asteroseismology has had a significant impact on the study of solar-type and red-giant stars, which exhibit convection-driven, solar-like oscillations. These studies have advanced considerably with space-based observatories like CoRoT (CNES/ESA) and Kepler (NASA), and are set to continue in the next decade with TESS and PLATO (ESA).

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    About Phys.org in 100 Words

    Phys.org™ (formerly Physorg.com) is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004, Phys.org’s readership has grown steadily to include 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

Compose new post
Next post/Next comment
Previous post/Previous comment
Show/Hide comments
Go to top
Go to login
Show/Hide help
shift + esc
%d bloggers like this: