Tagged: NASA Spitzer Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 3:40 pm on May 11, 2017 Permalink | Reply
    Tags: , , “Warm Neptune” HAT-P-26b, , , NASA Spitzer,   

    From Goddard: “NASA Study Finds Unexpectedly Primitive Atmosphere Around ‘Warm Neptune’ “ 

    NASA Goddard Banner
    NASA Goddard Space Flight Center

    May 11, 2017
    Elizabeth Zubritsky
    elizabeth.a.zubritsky@nasa.gov
    Nancy Neal-Jones
    nancy.n.jones@nasa.gov
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    Elizabeth Landau
    elizabeth.landau@jpl.nasa.gov
    Jet Propulsion Laboratory, Pasadena, Calif.

    1
    The atmosphere of the distant “warm Neptune” HAT-P-26b, illustrated here, is unexpectedly primitive, composed primarily of hydrogen and helium. By combining observations from NASA’s Hubble and Spitzer space telescopes, researchers determined that, unlike Neptune and Uranus, the exoplanet has relatively low metallicity, an indication of the how rich the planet is in all elements heavier than hydrogen and helium.
    Credits: NASA/GSFC

    A study [Science]combining observations from NASA’s Hubble and Spitzer space telescopes reveals that the distant planet HAT-P-26b has a primitive atmosphere composed almost entirely of hydrogen and helium.

    NASA/ESA Hubble Telescope

    NASA/Spitzer Telescope

    Located about 437 light years away, HAT-P-26b orbits a star roughly twice as old as the sun.

    2
    http://www.vladtime.ru/nauka/464041

    The analysis is one of the most detailed studies to date of a “warm Neptune,” or a planet that is Neptune-sized and close to its star. The researchers determined that HAT-P-26b’s atmosphere is relatively clear of clouds and has a strong water signature, although the planet is not a water world. This is the best measurement of water to date on an exoplanet of this size.

    The discovery of an atmosphere with this composition on this exoplanet has implications for how scientists think about the birth and development of planetary systems. Compared to Neptune and Uranus, the planets in our solar system with about the same mass, HAT-P-26b likely formed either closer to its host star or later in the development of its planetary system, or both.

    “Astronomers have just begun to investigate the atmospheres of these distant Neptune-mass planets, and almost right away, we found an example that goes against the trend in our solar system,” said Hannah Wakeford, a postdoctoral researcher at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the study published in the May 12, 2017, issue of Science. “This kind of unexpected result is why I really love exploring the atmospheres of alien planets.”

    To study HAT-P-26b’s atmosphere, the researchers used data from transits— occasions when the planet passed in front of its host star. During a transit, a fraction of the starlight gets filtered through the planet’s atmosphere, which absorbs some wavelengths of light but not others. By looking at how the signatures of the starlight change as a result of this filtering, researchers can work backward to figure out the chemical composition of the atmosphere.

    In this case, the team pooled data from four transits measured by Hubble and two seen by Spitzer. Together, those observations covered a wide range of wavelengths from yellow light through the near-infrared region.

    “To have so much information about a warm Neptune is still rare, so analyzing these data sets simultaneously is an achievement in and of itself,” said co-author Tiffany Kataria of NASA’s Jet Propulsion Laboratory in Pasadena, California.

    Because the study provided a precise measurement of water, the researchers were able to use the water signature to estimate HAT-P-26b’s metallicity. Astronomers calculate the metallicity, an indication of how rich the planet is in all elements heavier than hydrogen and helium, because it gives them clues about how a planet formed.

    To compare planets by their metallicities, scientists use the sun as a point of reference, almost like describing how much caffeine beverages have by comparing them to a cup of coffee. Jupiter has a metallicity about 2 to 5 times that of the sun. For Saturn, it’s about 10 times as much as the sun. These relatively low values mean that the two gas giants are made almost entirely of hydrogen and helium.

    The ice giants Neptune and Uranus are smaller than the gas giants but richer in the heavier elements, with metallicities of about 100 times that of the sun. So, for the four outer planets in our solar system, the trend is that the metallicities are lower for the bigger planets.

    Scientists think this happened because, as the solar system was taking shape, Neptune and Uranus formed in a region toward the outskirts of the enormous disk of dust, gas and debris that swirled around the immature sun. Summing up the complicated process of planetary formation in a nutshell: Neptune and Uranus would have been bombarded with a lot of icy debris that was rich in heavier elements. Jupiter and Saturn, which formed in a warmer part of the disk, would have encountered less of the icy debris.

    Two planets beyond our solar system also fit this trend. One is the Neptune-mass planet HAT-P-11b. The other is WASP-43b, a gas giant twice as massive as Jupiter.

    But Wakeford and her colleagues found that HAT-P-26b bucks the trend. They determined its metallicity is only about 4.8 times that of the sun, much closer to the value for Jupiter than for Neptune.

    “This analysis shows that there is a lot more diversity in the atmospheres of these exoplanets than we were expecting, which is providing insight into how planets can form and evolve differently than in our solar system,” said David K. Sing of the University of Exeter and the second author of the paper. “I would say that has been a theme in the studies of exoplanets: Researchers keep finding surprising diversity.”

    The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington.

    NASA’s Jet Propulsion Laboratory in Pasadena, California, manages the Spitzer Space Telescope for NASA’s Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at Caltech in Pasadena. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. Data are archived at the Infrared Science Archive housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA.

    For more information about Spitzer, visit:

    http://www.nasa.gov/spitzer

    For images and more information about Hubble, visit:

    http://www.nasa.gov/hubble

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.


    NASA/Goddard Campus

    Advertisements
     
  • richardmitnick 11:55 am on April 26, 2017 Permalink | Reply
    Tags: , NASA Spitzer, New planet OGLE-2016-BLG-1195Lb found   

    From Spitzer: “Iceball’ Planet Discovered Through Microlensing” 

    NASA Spitzer Telescope

    Spitzer

    04.26.17
    Elizabeth Landau
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-354-6425
    elizabeth.landau@jpl.nasa.gov

    1

    Scientists have discovered a new planet with the mass of Earth, orbiting its star at the same distance that we orbit our sun. The planet is likely far too cold to be habitable for life as we know it, however, because its star is so faint. But the discovery adds to scientists’ understanding of the types of planetary systems that exist beyond our own.

    “This ‘iceball’ planet is the lowest-mass planet ever found through microlensing,” said Yossi Shvartzvald, a NASA postdoctoral fellow based at NASA’s Jet Propulsion Laboratory, Pasadena, California, and lead author of a study published in the Astrophysical Journal Letters.

    Gravitational microlensing, S. Liebes, Physical Review B, 133 (1964): 835

    Microlensing is a technique that facilitates the discovery of distant objects by using background stars as flashlights. When a star crosses precisely in front of a bright star in the background, the gravity of the foreground star focuses the light of the background star, making it appear brighter. A planet orbiting the foreground object may cause an additional blip in the star’s brightness. In this case, the blip only lasted a few hours. This technique has found the most distant known exoplanets from Earth, and can detect low-mass planets that are substantially farther from their stars than Earth is from our sun.

    The newly discovered planet, called OGLE-2016-BLG-1195Lb, aids scientists in their quest to figure out the distribution of planets in our galaxy. An open question is whether there is a difference in the frequency of planets in the Milky Way’s central bulge compared to its disk, the pancake-like region surrounding the bulge. OGLE-2016-BLG-1195Lb is located in the disk, as are two planets previously detected through microlensing by NASA’s Spitzer Space Telescope.

    “Although we only have a handful of planetary systems with well-determined distances that are this far outside our solar system, the lack of Spitzer detections in the bulge suggests that planets may be less common toward the center of our galaxy than in the disk,” said Geoff Bryden, astronomer at JPL and co-author of the study.

    For the new study, researchers were alerted to the initial microlensing event by the ground-based Optical Gravitational Lensing Experiment (OGLE) survey, managed by the University of Warsaw in Poland. Study authors used the Korea Microlensing Telescope Network (KMTNet), operated by the Korea Astronomy and Space Science Institute, and Spitzer, to track the event from Earth and space.

    3
    KMTNet-CTIO

    1.3 meter OGLE Warsaw Telescope at the Las Campanas Observatory in Chile

    KMTNet consists of three wide-field telescopes: one in Chile, one in Australia, and one in South Africa. When scientists from the Spitzer team received the OGLE alert, they realized the potential for a planetary discovery. The microlensing event alert was only a couple of hours before Spitzer’s targets for the week were to be finalized, but it made the cut.

    With both KMTNet and Spitzer observing the event, scientists had two vantage points from which to study the objects involved, as though two eyes separated by a great distance were viewing it. Having data from these two perspectives allowed them to detect the planet with KMTNet and calculate the mass of the star and the planet using Spitzer data.

    “We are able to know details about this planet because of the synergy between KMTNet and Spitzer,” said Andrew Gould, professor emeritus of astronomy at Ohio State University, Columbus, and study co-author.

    Although OGLE-2016-BLG-1195Lb is about the same mass as Earth, and the same distance from its host star as our planet is from our sun, the similarities may end there.

    OGLE-2016-BLG-1195Lb is nearly 13,000 light-years away and orbits a star so small, scientists aren’t sure if it’s a star at all. It could be a brown dwarf, a star-like object whose core is not hot enough to generate energy through nuclear fusion. This particular star is only 7.8 percent the mass of our sun, right on the border between being a star and not.

    Alternatively, it could be an ultra-cool dwarf star much like TRAPPIST-1, which Spitzer and ground-based telescopes recently revealed to host seven Earth-size planets.

    The TRAPPIST-1 star, an ultracool dwarf, is orbited by seven Earth-size planets (NASA).

    Those seven planets all huddle closely around TRAPPIST-1, even closer than Mercury orbits our sun, and they all have potential for liquid water. But OGLE-2016-BLG-1195Lb, at the sun-Earth distance from a very faint star, would be extremely cold — likely even colder than Pluto is in our own solar system, such that any surface water would be frozen. A planet would need to orbit much closer to the tiny, faint star to receive enough light to maintain liquid water on its surface.

    Ground-based telescopes available today are not able to find smaller planets than this one using the microlensing method. A highly sensitive space telescope would be needed to spot smaller bodies in microlensing events. NASA’s upcoming Wide Field Infrared Survey Telescope (WFIRST), planned for launch in the mid-2020s, will have this capability.

    NASA/WFIRST

    “One of the problems with estimating how many planets like this are out there is that we have reached the lower limit of planet masses that we can currently detect with microlensing,” Shvartzvald said. “WFIRST will be able to change that.”

    JPL manages the Spitzer Space Telescope mission for NASA’s Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at Caltech in Pasadena, California. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. Data are archived at the Infrared Science Archive housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA. For more information about Spitzer, visit:

    http://spitzer.caltech.edu

    http://www.nasa.gov/spitzer

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory located on the campus of the California Institute of Technology and part of NASA’s Infrared Processing and Analysis Center.

    NASA image

    NASA JPL Icon

    Caltech Logo

     
  • richardmitnick 4:57 pm on April 24, 2017 Permalink | Reply
    Tags: , , , , NASA Spitzer, Where Is Spitzer Now?   

    From Spitzer: “Where Is Spitzer Now?” 

    NASA Spitzer Telescope

    Spitzer

    1

    Current Observation Details
    Target Name NGC1385
    RA 3:37:28.32
    Declination -24:30: 4.60
    Program Name SPIRITS1 1
    Principal Investigator Kasliwal
    AOT iracmapp
    Start Time 2017-04-24 21:43:34 UTC
    Duration of Observation 29.39

    How To Read The Details
    Target Name
    This is the name of the object being observed by Spitzer. The name appears as it was input by the observer, and will usually appear as a unique, universally accepted catalog designation rather than a “name” in the traditional sense of the word.
    RA
    These are the coordinates in the sky where the object is located. They work much like longitude and latitude on Earth. RA is the object’s position along the equator, and Declination is its position north or south (positive numbers are the northern sky, and negative numbers are the southern sky).
    Declination
    These are the coordinates in the sky where the object is located. They work much like longitude and latitude on Earth. RA is the object’s position along the equator, and Declination is its position north or south (positive numbers are the northern sky, and negative numbers are the southern sky).
    Program Name
    When astronomers are granted observing time on Spitzer, their planned observations are defined under a unique program name. Each program has specific goals and objectives, such as the various Legacy Science programs, whose objective is to create a substantial and coherent database of archived observations that can be used by subsequent Spitzer researchers.
    Principal Investigator
    This is the name of the scientist who leads the team of people who are making the observation on Spitzer.
    AOT
    This is the specific observing mode that Spitzer is using for its observation. Spitzer has three different instruments (IRAC – The Infrared Array Camera, IRS – The Infrared Spectrograph, and MIPS – The Multiband Imaging Photometer for Spitzer), all of which can be used in several different ways.
    Start Time
    The time that the observation began. The times are given in UTC (also known as Greenwich Mean Time), which is 8 hours ahead of Pacific Standard Time (7 hours ahead of Pacific Daylight Time).
    Duration of Observation

    Different observations require different amounts of time to gather all the data. Some observations can be quite quick, and some can take hours.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory located on the campus of the California Institute of Technology and part of NASA’s Infrared Processing and Analysis Center.

    NASA image

    NASA JPL Icon

    Caltech Logo

     
  • richardmitnick 1:35 pm on November 12, 2016 Permalink | Reply
    Tags: , , NASA Space Telescopes Pinpoint Elusive Brown Dwarf, NASA Spitzer   

    From Spitzer: “NASA Space Telescopes Pinpoint Elusive Brown Dwarf” 

    NASA Spitzer Telescope

    Spitzer

    11.10.16

    1

    In a first-of-its-kind collaboration, NASA’s Spitzer and Swift space telescopes joined forces to observe a microlensing event, when a distant star brightens due to the gravitational field of at least one foreground cosmic object.

    NASA/SWIFT Telescope
    NASA/SWIFT Telescope

    2
    That picture above is real! It’s a Hubble Space Telescope image of a cluster of galaxies with the poetic name of SDSS J1038+4849 (called that because it was first seen in the Sloan Digital Sky Survey, and the numbers are its coordinates, like latitude and longitude, on the sky). What you’re seeing is a peculiar effect of relativity called “gravitational lensing.”

    This technique is useful for finding low-mass bodies orbiting stars, such as planets. In this case, the observations revealed a brown dwarf.

    Brown Dwarf 2M1207A and companion 2M120B
    Brown Dwarf 2M1207A and companion 2M120B

    Brown dwarfs are thought to be the missing link between planets and stars, with masses up to 80 times that of Jupiter. But their centers are not hot or dense enough to generate energy through nuclear fusion the way stars do. Curiously, scientists have found that, for stars roughly the mass of our sun, less than 1 percent have a brown dwarf orbiting within 3 AU (1 AU is the distance between Earth and the sun). This phenomenon is called the “brown dwarf desert.”

    The newly discovered brown dwarf, which orbits a host star, may inhabit this desert. Spitzer and Swift observed the microlensing event after being tipped off by ground-based microlensing surveys, including the Optical Gravitational Lensing Experiment (OGLE).

    OGLE Warsaw Telescope at the Las Campanas Observatory in Chile
    1.3 meter OGLE Warsaw telescope interior
    1.3 meter OGLE Warsaw Telescope at the Las Campanas Observatory in Chile

    The discovery of this brown dwarf, with the unwieldy name OGLE-2015-BLG-1319, marks the first time two space telescopes have collaborated to observe a microlensing event.

    “We want to understand how brown dwarfs form around stars, and why there is a gap in where they are found relative to their host stars,” said Yossi Shvartzvald, a NASA postdoctoral fellow based at NASA’s Jet Propulsion Laboratory, Pasadena, California, and lead author of a study published in the Astrophysical Journal. “It’s possible that the ‘desert’ is not as dry as we think.”

    What is microlensing?

    n a microlensing event, a background source star serves as a flashlight for the observer. When a massive object passes in front of the background star along the line of sight, the background star brightens because the foreground object deflects and focuses the light from the background source star. Depending on the mass and alignment of the intervening object, the background star can briefly appear thousands of times brighter.

    One way to understand better the properties of the lensing system is to observe the microlensing event from more than one vantage point. By having multiple telescopes record the brightening of the background star, scientists can take advantage of “parallax,” the apparent difference in position of an object as seen from two points in space. When you hold your thumb in front of your nose and close your left eye, then open it and close your right eye, your thumb seems to move in space — but it stays put with two eyes open. In the context of microlensing, observing the same event from two or more widely separated locations will result in different magnification patterns.

    “Anytime you have multiple observing locations, such as Earth and one, or in this case, two space telescopes, it’s like having multiple eyes to see how far away something is,” Shvartzvald said. “From models for how microlensing works, we can then use this to calculate the relationship between the mass of the object and its distance.”

    The new study

    Spitzer observed the binary system containing the brown dwarf in July 2015, during the last two weeks of the space telescope’s microlensing campaign for that year.
    While Spitzer is over 1 AU away from Earth in an Earth-trailing orbit around the sun, Swift is in a low Earth orbit encircling our planet. Swift also saw the binary system in late June 2015 through microlensing, representing the first time this telescope had observed a microlensing event. But Swift is not far enough away from ground-based telescopes to get a significantly different view of this particular event, so no parallax was measured between the two. This gives scientists insights into the limits of the telescope’s capabilities for certain types of objects and distances.

    “Our simulations suggest that Swift could measure this parallax for nearby, less massive objects, including ‘free-floating planets,’ which do not orbit stars,” Shvartzvald said.

    By combining data from these space-based and ground-based telescopes, researchers determined that the newly discovered brown dwarf is between 30 and 65 Jupiter masses. They also found that the brown dwarf orbits a K dwarf, a type of star that tends to have about half the mass of the sun. Researchers found two possible distances between the brown dwarf and its host star, based on available data: 0.25 AU and 45 AU. The 0.25 AU distance would put this system in the brown dwarf desert.

    “In the future, we hope to have more observations of microlensing events from multiple viewing perspectives, allowing us to probe further the characteristics of brown dwarfs and planetary systems,” said Geoffrey Bryden, JPL scientist and co-author of the study.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory located on the campus of the California Institute of Technology and part of NASA’s Infrared Processing and Analysis Center.

    NASA image

    NASA JPL Icon

    Caltech Logo

     
  • richardmitnick 2:45 pm on September 28, 2016 Permalink | Reply
    Tags: , , , , NASA Spitzer, The Frontier Fields: Where Primordial Galaxies Lurk   

    From JPL-Caltech: “The Frontier Fields: Where Primordial Galaxies Lurk” 

    NASA JPL Banner

    JPL-Caltech

    September 28, 2016
    Elizabeth Landau
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-354-6425
    elizabeth.landau@jpl.nasa.gov

    Written by Adam Hadhazy

    1
    This image of galaxy cluster Abell 2744, also called Pandora’s Cluster, was taken by the Spitzer Space Telescope. The cluster is also being studied by NASA’s Hubble Space Telescope and Chandra X-Ray Observatory in a collaboration called the Frontier Fields project. Image credit:NASA/JPL-Caltech.

    NASA/Spitzer Telescope
    NASA/Spitzer Telescope

    NASA/ESA Hubble Telescope
    NASA/ESA Hubble Telescope

    NASA/Chandra Telescope
    NASA/Chandra Telescope

    In the ongoing hunt for the universe’s earliest galaxies, NASA’s Spitzer Space Telescope has wrapped up its observations for the Frontier Fields project. This ambitious project has combined the power of all three of NASA’s Great Observatories — Spitzer, the Hubble Space Telescope and the Chandra X-ray Observatory — to delve as far back in time and space as current technology can allow.

    Even with today’s best telescopes, it is difficult to gather enough light from the very first galaxies, located more than 13 billion light years away, to learn much about them beyond their approximate distance. But scientists have a tool of cosmic proportions to help in their studies. The gravity exerted by massive, foreground clusters of galaxies bends and magnifies the light of faraway, background objects, in effect creating cosmic zoom lenses. This phenomenon is called gravitational lensing.

    The Frontier Fields observations have peered through the strongest zoom lenses available by targeting six of the most massive galaxy clusters known. These lenses can magnify tiny background galaxies by as much as a factor of one hundred. With Spitzer’s new Frontier Fields data, along with data from Chandra and Hubble, astronomers will learn unprecedented details about the earliest galaxies.

    “Spitzer has finished its Frontier Fields observations and we are very excited to get all of this data out to the astronomical community,” said Peter Capak, a research scientist with the NASA/JPL Spitzer Science Center at Caltech in Pasadena, California, and the Spitzer lead for the Frontier Fields project.

    A recent paper published in the journal Astronomy & Astrophysics presented the full catalog data for two of the six galaxy clusters studied by the Frontier Fields: Abell 2744 — nicknamed Pandora’s Cluster — and MACS J0416, both located about four billion light years away. The other galaxy clusters selected for Frontier Fields are RXC J2248, MACS J1149, MACS J0717 and Abell 370.

    Eager astronomers will comb the Frontier Fields catalogs for the tiniest, dimmest-lensed objects, many of which should prove to be the most distant galaxies ever glimpsed. The current record-holder, a galaxy called GN-z11, was reported in March by Hubble researchers at the astonishing distance of 13.4 billion light-years, only a few hundred million years after the big bang. The discovery of this galaxy did not require gravitational lenses because it is an outlying, extremely bright object for its epoch. With the magnification boost provided by gravitational lenses, the Frontier Fields project will allow researchers to study typical objects at such incredible distances, painting a more accurate and complete picture of the universe’s earliest galaxies.

    Astronomers want to understand how these primeval galaxies arose, how their constituent mass developed into stars, and how these stars have enriched the galaxies with chemical elements fused in their thermonuclear furnaces. To learn about the origin and evolution of the earliest galaxies, which are quite faint, astronomers need to collect as much light as possible across a range of frequencies. With sufficient light from these galaxies, astronomers can perform spectroscopy, pulling out details about stars’ compositions, temperatures and their environments by examining the signatures of chemical elements imprinted in the light.

    “With the Frontier Fields approach,” said Capak, “the most remote and faintest galaxies are made bright enough for us to start to say some definite things about them, such as their star formation histories.”

    Because the universe has expanded over its 13.8-billion-year history, light from extremely distant objects has been stretched out, or redshifted, on its long journey to Earth. Optical light emitted by stars in the gravitational-lensed, background galaxies viewed in the Frontier Fields has therefore redshifted into infrared. Spitzer can use this infrared light to gauge the population sizes of stars in a galaxy, which in turn gives clues to the galaxy’s mass. Combining the light seen by Spitzer and Hubble allows astronomers to identify galaxies at the edge of the observable universe.

    Hubble, meanwhile, scans the Frontier Fields galaxy clusters in optical and near-infrared light, which has redshifted from ultraviolet light on its journey to Earth. Chandra, for its part, observes the foreground galaxy clusters in high-energy X-rays emitted by black holes and ambient hot gas. Along with Spitzer, the space telescopes size up the masses of the galaxy clusters, including their unseen but substantial dark matter content. Nailing down the clusters’ total mass is a critical step in quantifying the magnification and distortion they produce on background galaxies of interest. Recent multi-wavelength results in this vein from the Frontier Fields project regarding the MACS J0416 and MACS J0717 clusters were published in October 2015 and February 2016. These results also brought in radio wave observations from the Karl G. Jansky Very Large Array to see star-forming regions otherwise hidden by gas and dust.

    The Frontier Fields collaboration has inspired scientists involved in the effort as they look ahead to delving even deeper into the universe with the James Webb Space Telescope, which is planned for launch in 2018.

    “The Frontier Fields has been an entirely community-led project, which is different from the way many projects of this magnitude are typically pursued,” said Lisa Storrie-Lombardi of the Spitzer Science Center, also with the Frontier Fields project. “People have gotten together and really embraced Frontier Fields.”

    In addition to the six Frontier Fields galaxy clusters, Spitzer has done follow-up observations on other, slightly shallower fields Hubble has gazed into, expanding the overall number of cosmic regions where fairly deep observations have been taken. These additional fields will further serve as rich areas of investigation for Webb and future instruments.

    NASA’s Jet Propulsion Laboratory, Pasadena, California, manages the Spitzer Space Telescope mission for NASA’s Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at Caltech. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. Data are archived at the Infrared Science Archive, housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA.

    For more information about Spitzer, visit:

    http://www.nasa.gov/spitzer

    http://spitzer.caltech.edu

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

    Caltech Logo

    NASA image

     
  • richardmitnick 12:54 pm on September 8, 2016 Permalink | Reply
    Tags: 'Enterprise' Nebulae Seen by Spitzer (annotated), , , NASA Spitzer   

    From Spitzer: “‘Enterprise’ Nebulae Seen by Spitzer (annotated)” 

    NASA Spitzer Telescope

    Spitzer

    09.08.16

    1

    Just in time for the 50th anniversary of the TV series “Star Trek,” which first aired September 8th,1966, a new infrared image from NASA’s Spitzer Space Telescope may remind fans of the historic show.

    Since ancient times, people have imagined familiar objects when gazing at the heavens. There are many examples of this phenomenon, known as pareidolia, including the constellations and the well-known nebulae named Ant, Stingray and Hourglass.

    On the right of the image, the sketch shows hints of the saucer and hull of the original USS Enterprise, captained by James T. Kirk, as if it were emerging from a dark nebula. To the left, its “Next Generation” successor, Jean-Luc Picard’s Enterprise-D, flies off in the opposite direction.

    Astronomically speaking, the region pictured in the image falls within the disk of our Milky Way galaxy and displays two regions of star formation hidden behind a haze of dust when viewed in visible light. Spitzer’s ability to peer deeper into dust clouds has revealed a myriad of stellar birthplaces like these, which are officially known only by their catalog numbers, IRAS 19340+2016 and IRAS 19343+2026.

    Trekkies, however, may prefer using the more familiar designations NCC-1701 and NCC-1701-D. Fifty years after its inception, Star Trek still inspires fans and astronomers alike to boldly explore where no one has gone before.

    This image was assembled using data from Spitzer’s biggest surveys of the Milky Way, called GLIMPSE and MIPSGAL. Light with a wavelength of 3.5 microns is shown in blue, 8.0 microns in green, and 24 microns in red. The green colors highlight organic molecules in the dust clouds, illuminated by starlight. Red colors are related to thermal radiation emitted from the very hottest areas of dust.

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory located on the campus of the California Institute of Technology and part of NASA’s Infrared Processing and Analysis Center.

    NASA image

    NASA JPL Icon

     
  • richardmitnick 1:08 pm on August 29, 2016 Permalink | Reply
    Tags: , , IRAS 19312+1950, , NASA Spitzer   

    From JPL: “NASA Team Probes Peculiar Age-Defying Star” 

    NASA JPL Banner

    JPL-Caltech

    August 29, 2016
    Elizabeth Landau
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-354-6425
    elizabeth.landau@jpl.nasa.gov

    Written by Elizabeth Zubritsky
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    1
    An age-defying star called IRAS 19312+1950 exhibits features characteristic of a very young star and a very old star. The object stands out as extremely bright inside a large, chemically rich cloud of material, as shown in this image from NASA’s Spitzer Space Telescope. IRAS 19312+1950 is the bright red star in the center of this image. Image credit: NASA/JPL-Caltech

    A NASA-led team of scientists thinks the star — which is about 10 times as massive as our sun and emits about 20,000 times as much energy — is a newly forming protostar. That was a big surprise, because the region had not been known as a stellar nursery before. But the presence of a nearby interstellar bubble, which indicates the presence of a recently formed massive star, also supports this idea.

    For years, astronomers have puzzled over a massive star lodged deep in the Milky Way that shows conflicting signs of being extremely old and extremely young.

    Researchers initially classified the star as elderly, perhaps a red supergiant. But a new study by a NASA-led team of researchers suggests that the object, labeled IRAS 19312+1950, might be something quite different — a protostar, a star still in the making.

    “Astronomers recognized this object as noteworthy around the year 2000 and have been trying ever since to decide how far along its development is,” said Martin Cordiner, an astrochemist working at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. He is the lead author of a paper in the Astrophysical Journal describing the team’s findings, from observations made using NASA’s Spitzer Space Telescope and ESA’s Herschel Space Observatory.

    NASA/Spitzer Telescope
    NASA/Spitzer Telescope

    ESA/Herschel
    ESA/Herschel

    Located more than 12,000 light-years from Earth, the object first stood out as peculiar when it was observed at particular radio frequencies. Several teams of astronomers studied it using ground-based telescopes and concluded that it is an oxygen-rich star about 10 times as massive as the sun. The question was: What kind of star?

    Some researchers favor the idea that the star is evolved — past the peak of its life cycle and on the decline. For most of their lives, stars obtain their energy by fusing hydrogen in their cores, as the sun does now. But older stars have used up most of their hydrogen and must rely on heavier fuels that don’t last as long, leading to rapid deterioration.

    Two early clues — intense radio sources called masers — suggested the star was old. In astronomy, masers occur when the molecules in certain kinds of gases get revved up and emit a lot of radiation over a very limited range of frequencies. The result is a powerful radio beacon — the microwave equivalent of a laser.

    One maser observed with IRAS 19312+1950 is almost exclusively associated with late-stage stars. This is the silicon oxide maser, produced by molecules made of one silicon atom and one oxygen atom. Researchers don’t know why this maser is nearly always restricted to elderly stars, but of thousands of known silicon oxide masers, only a few exceptions to this rule have been noted.

    Also spotted with the star was a hydroxyl maser, produced by molecules comprised of one oxygen atom and one hydrogen atom. Hydroxyl masers can occur in various kinds of astronomical objects, but when one occurs with an elderly star, the radio signal has a distinctive pattern — it’s especially strong at a frequency of 1612 megahertz. That’s the pattern researchers found in this case.

    Even so, the object didn’t entirely fit with evolved stars. Especially puzzling was the smorgasbord of chemicals found in the large cloud of material surrounding the star. A chemical-rich cloud like this is typical of the regions where new stars are born, but no such stellar nursery had been identified near this star.

    Scientists initially proposed that the object was an old star surrounded by a surprising cloud typical of the kind that usually accompanies young stars. Another idea was that the observations might somehow be capturing two objects: a very old star and an embryonic cloud of star-making material in the same field.

    Cordiner and his colleagues began to reconsider the object, conducting observations using ESA’s Herschel Space Observatory and analyzing data gathered earlier with NASA’s Spitzer Space Telescope. Both telescopes operate at infrared wavelengths, which gave the team new insight into the gases, dust and ices in the cloud surrounding the star.

    The additional information leads Cordiner and colleagues to think the star is in a very early stage of formation. The object is much brighter than it first appeared, they say, emitting about 20,000 times the energy of our sun. The team found large quantities of ices made from water and carbon dioxide in the cloud around the object. These ices are located on dust grains relatively close to the star, and all this dust and ice blocks out starlight making the star seem dimmer than it really is.

    In addition, the dense cloud around the object appears to be collapsing, which happens when a growing star pulls in material. In contrast, the material around an evolved star is expanding and is in the process of escaping to the interstellar medium. The entire envelope of material has an estimated mass of 500 to 700 suns, which is much more than could have been produced by an elderly or dying star.

    “We think the star is probably in an embryonic stage, getting near the end of its accretion stage — the period when it pulls in new material to fuel its growth,” said Cordiner.

    Also supporting the idea of a young star are the very fast wind speeds measured in two jets of gas streaming away from opposite poles of the star. Such jets of material, known as a bipolar outflow, can be seen emanating from young or old stars. However, fast, narrowly focused jets are rarely observed in evolved stars. In this case, the team measured winds at the breakneck speed of at least 200,000 miles per hour (90 kilometers per second) — a common characteristic of a protostar.

    Still, the researchers acknowledge that the object is not a typical protostar. For reasons they can’t explain yet, the star has spectacular features of both a very young and a very old star.

    “No matter how one looks at this object, it’s fascinating, and it has something new to tell us about the life cycles of stars,” said Steven Charnley, a Goddard astrochemist and co-author of the paper.

    NASA’s Jet Propulsion Laboratory in Pasadena, California, manages the Spitzer Space Telescope mission, whose science operations are conducted at the Spitzer Science Center. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado.

    Herschel is an ESA space observatory with science instruments provided by European-led principal investigator consortia and with important participation from NASA.

    For more information, visit:

    http://www.nasa.gov/spitzer

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

    Caltech Logo
    jpl

    NASA image

     
  • richardmitnick 8:11 pm on August 25, 2016 Permalink | Reply
    Tags: , , , NASA Spitzer   

    From JPL-Caltech: “Spitzer Space Telescope Begins ‘Beyond’ Phase” 

    NASA JPL Banner

    JPL-Caltech

    NASA Spitzer Telescope
    Spitzer

    August 25, 2016

    Elizabeth Landau
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-354-6425
    elizabeth.landau@jpl.nasa.gov

    1

    Spitzer Space Telescope Begins ‘Beyond’ Phase

    This diagram shows how the different phases of Spitzer’s mission relate to its location relative to the Earth over time.Credit: NASA/JPL-Caltech

    Celebrating the spacecraft’s ability to push the boundaries of space science and technology, NASA’s Spitzer Space Telescope team has dubbed the next phase of its journey “Beyond.”

    “Spitzer is operating well beyond the limits that were set for it at the beginning of the mission,” said Michael Werner, the project scientist for Spitzer at NASA’s Jet Propulsion Laboratory in Pasadena, California. “We never envisioned operating 13 years after launch, and scientists are making discoveries in areas of science we never imagined exploring with the spacecraft.”

    NASA recently granted the spacecraft a two-and-a-half-year mission extension. This Beyond phase of the Spitzer mission will explore a wide range of topics in astronomy and cosmology, as well as planetary bodies in and out of our solar system.

    Because of Spitzer’s orbit and age, the Beyond phase presents a variety of new engineering challenges. Spitzer trails Earth in its journey around the sun, but because the spacecraft travels slower than Earth, the distance between Spitzer and Earth has widened over time. As Spitzer gets farther away, its antenna must be pointed at higher angles toward the sun to communicate with Earth, which means that parts of the spacecraft will experience more and more heat. At the same time, Spitzer’s solar panels point away from the sun and will receive less sunlight, so the batteries will be under greater stress. To enable this riskier mode of operations, the mission team will have to override some autonomous safety systems.

    “Balancing these concerns on a heat-sensitive spacecraft will be a delicate dance, but engineers are hard at work preparing for the new challenges in the Beyond phase,” said Mark Effertz, the Spitzer spacecraft chief engineer at Lockheed Martin Space Systems Company, Littleton, Colorado, which built the spacecraft.

    Spitzer, which launched on Aug. 25, 2003, has consistently adapted to new scientific and engineering challenges during its mission, and the team expects it will continue to do so during the “Beyond” phase, which begins Oct. 1. The selected research proposals for the Beyond phase, also known as Cycle 13, include a variety of objects that Spitzer wasn’t originally planned to address — such as galaxies in the early universe, the black hole at the center of the Milky Way and exoplanets.

    Sag A*  NASA Chandra X-Ray Observatory 23 July 2014, the supermassive black hole at the center of the Milky Way
    Sag A* NASA Chandra X-Ray Observatory 23 July 2014, the supermassive black hole at the center of the Milky Way

    “We never even considered using Spitzer for studying exoplanets when it launched,” said Sean Carey of NASA’s Spitzer Science Center at Caltech in Pasadena. “It would have seemed ludicrous back then, but now it’s an important part of what Spitzer does.”

    Spitzer’s exoplanet exploration

    Spitzer has many qualities that make it a valuable asset in exoplanet science, including an extremely accurate star-targeting system and the ability to control unwanted changes in temperature. Its stable environment and ability to observe stars for long periods of time led to the first detection of light from known exoplanets in 2005. More recently, Spitzer’s Infrared Array Camera (IRAC) has been used for finding exoplanets using the “transit” method — looking for a dip in a star’s brightness that corresponds to a planet passing in front of it. This brightness change needs to be measured with exquisite accuracy to detect exoplanets. IRAC scientists have created a special type of observation to make such measurements, using single pixels within the camera.

    Another planet-finding technique that Spitzer uses, but was not designed for, is called microlensing. When a star passes in front of another star, the gravity of the first star can act as a lens, making the light from the more distant star appear brighter. Scientists are using microlensing to look for a blip in that brightening, which could mean that the foreground star has a planet orbiting it. Spitzer and the ground-based Polish Optical Gravitational Lensing Experiment (OGLE) were used together to find one of the most distant planets known outside the solar system, as reported in 2015. This type of investigation is made possible by Spitzer’s increasing distance from Earth, and could not have been done early in the mission.

    Peering into the early universe

    Understanding the early universe is another area where Spitzer has broken ground. IRAC was designed to detect remote galaxies roughly 12 billion light-years away — so distant that their light has been traveling for roughly 88 percent of the history of the universe. But now, thanks to collaborations between Spitzer and NASA’s Hubble Space Telescope, scientists can peer even further into the past. The farthest galaxy ever seen, GN-z11, was characterized in a 2016 study using data from these telescopes. GN-z11 is about 13.4 billion light-years away, meaning its light has been traveling since 400 million years after the big bang.

    “When we designed the IRAC instrument, we didn’t know those more distant galaxies existed,” said Giovanni Fazio, principal investigator of IRAC, based at the Harvard Smithsonian Center for Astrophysics in Cambridge, Massachusetts. “The combination of the Hubble Space Telescope and Spitzer has been fantastic, with the telescopes working together to determine their distance, stellar mass and age.”

    Closer to home, Spitzer advanced astronomers’ understanding of Saturn when scientists using the observatory discovered the planet’s largest ring in 2009. Most of the material in this ring — consisting of ice and dust — begins 3.7 million miles (6 million kilometers) from Saturn and extends about 7.4 million miles (12 million kilometers) beyond that. Though the ring doesn’t reflect much visible light, making it difficult for Earth-based telescopes to see, Spitzer could detect the infrared glow from the cool dust.

    The multiple phases of Spitzer

    Spitzer reinvented itself in May 2009 with its warm mission, after the depletion of the liquid helium coolant that was chilling its instruments since August 2003. At the conclusion of the “cold mission,” Spitzer’s Infrared Spectrograph and Multiband Imaging Photometer stopped working, but two of the four cameras in IRAC persisted. Since then, the spacecraft has made numerous discoveries despite operating in warmer conditions (which, at about minus 405 Fahrenheit or 30 Kelvin, is still cold by Earthly standards).

    “With the IRAC team and the Spitzer Science Center team working together, we’ve really learned how to operate the IRAC instrument better than we thought we could,” Fazio said. “The telescope is also very stable and in an excellent orbit for observing a large part of the sky.”

    Spitzer’s Beyond mission phase will last until the commissioning phase of NASA’s James Webb Space Telescope, currently planned to launch in October 2018. Spitzer is set to identify targets that Webb can later observe more intensely.

    “We are very excited to continue Spitzer in its Beyond phase. We fully expect new, exciting discoveries to be made over the next two-and-a-half years,” said Suzanne Dodd, project manager for Spitzer, based at JPL.

    JPL manages the Spitzer Space Telescope mission for NASA’s Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at Caltech in Pasadena, California. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. Data are archived at the Infrared Science Archive housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA. For more information about Spitzer, visit:

    http://spitzer.caltech.edu

    http://www.nasa.gov/spitzer

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

    Caltech Logo

    jpl

    NASA image

     
  • richardmitnick 3:31 pm on July 22, 2016 Permalink | Reply
    Tags: , , NASA Spitzer,   

    From Spitzer: “Seeing the Milky Way’s Giant Black Hole with New Eyes” 

    NASA Spitzer Telescope

    Spitzer

    07.21.16

    1

    At the center of our Milky Way galaxy lies a cosmic beast called Sagittarius A*. This supermassive black hole packs about four million sun-masses into a volume roughly the size of our solar system.

    Sag A*  NASA Chandra X-Ray Observatory 23 July 2014, the supermassive black hole at the center of the Milky Way
    Sag A* NASA Chandra X-Ray Observatory 23 July 2014, the supermassive black hole at the center of the Milky Way

    Recently, NASA’s Spitzer Space Telescope began exploring this exotic object. The telescope has observed a great many cosmic phenomena, from galaxy clusters to stellar nurseries during its 13-year career, but the black hole at the center of the Milky Way was never a part of the spacecraft designers’ plans.

    “A decade ago, no one would have taken you seriously if you had mentioned doing science like this with Spitzer,” said Varoujan Gorjian, a research astronomer at NASA’s Jet Propulsion Laboratory in Pasadena, California, who studies supermassive black holes. “We are very pleased that, because of its recent sensitivity boost, Spitzer can now serve as another arrow in our quiver when targeting the black hole at the heart of the Milky Way.”

    The sensitivity boost involves an observing mode originally intended to study exoplanets. It has given Spitzer the unexpected capability to monitor infrared flares emitted by this monster black hole, known as Sagittarius A* (pronounced “Sagittarius-A-star”). In a trial run in December 2013, Spitzer took an unprecedented 23-hour exposure. Though other telescopes have observed variability in the Sagittarius A* region, Spitzer was the first to observe it at the wavelength of 4.5 microns.

    Building on that success, a fresh round of observations has just been completed, with Spitzer observing Sagittarius A* simultaneously with NASA’s Chandra X-ray Observatory and the ground-based ALMA and SMA microwave observatories .

    NASA/Chandra Telescope
    NASA/Chandra Telescope

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at  Chajnantor plateau, at 5,000 metres
    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    SMA Submillimeter Array
    CfA SMA Submillimeter Array 8-element radio interferometer, Maunakea, Hawaii, USA

    Spitzer’s contributions will aid ongoing efforts in understanding why the Milky Way’s big black hole accretes, or gobbles up, material so calmly, compared to black holes in similar galaxies.

    “We can now use Spitzer to study the emission from the innermost regions of the accretion flow onto the black hole, near the event horizon,” said Joseph Hora, an astronomer at the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Massachusetts, and the lead author of a 2014 study in The Astrophysical Journal reporting Spitzer’s Sagittarius A* observations. The observing project was led by Giovanni Fazio, also of CfA, with collaborators including the University of California, Los Angeles (UCLA) Galactic Center group led by Andrea Ghez.

    Eyeing a monster

    Located 26,000 light years away, Sagittarius A* is completely obscured by dust. Radio telescopes on Earth were the first to hone in on Sagittarius A* because radio waves freely pass through this dust, as well as our planet’s atmosphere. Other critical insights into Sagittarius A* have since come from the Chandra telescope, which scoops up dust-penetrating X-rays in space.

    The study of Sagittarius A* in infrared light has been knottier, but hugely successful. Although infrared light can also penetrate dust, only certain infrared wavelengths transmit through Earth’s atmosphere. Plus, these sorts of observations must contend with infrared light emitted by both the atmosphere and telescopic equipment itself.

    Despite these obstacles, starting in the mid-1990s, the 10-meter Keck Telescope in Hawaii tracked the orbits of stars (in infrared) whipping about an unseen, colossal mass emitting radio waves and X-rays at the center of our galaxy.

    Keck Observatory, Mauna Kea, Hawaii, USA
    Keck Observatory, Mauna Kea, Hawaii, USA

    Ground-based observations more recently captured an outburst of infrared light from Sagittarius A* itself, presumably as it wolfed down some matter that had strayed too close. Researchers desperately want more of these sorts of observations of Sagittarius A*’s variability. Comparing these data in additional wavelengths to radio waves and X-rays will help them construct a thorough model for just how Sagittarius A* interacts with its cosmic environment.

    Encouraged by the Keck results, Fazio and colleagues began considering using Spitzer’s infrared camera to investigate Sagittarius A*. The odds did not look good, though. Because Spitzer’s resolution cannot match that of the Keck telescope, the light from Sagittarius A* would be blended with the light of the many bright stars in the black hole’s central galactic vicinity. Tracking its variability therefore seemed out of Spitzer’s reach.

    Unleashing Spitzer’s full power

    Fortunately, NASA engineers in the early 2010s were already seeking to increase Spitzer’s stability and targeting — essentially, its ability to pick one spot in the universe and stare at it with minimal wobbling. The intended purpose of this upgrade was to let Spitzer point fixedly at a star and watch for miniscule dimming as an exoplanet crossed, or transited. Such transits reveal an exoplanet’s size, as well as clues about its atmospheric composition.

    Planet transit. NASA/Ames
    Planet transit. NASA/Ames

    To achieve the necessary stability for exoplanet studies, Spitzer’s engineers took three steps. First, in October 2010, they figured out an intermittent wobble within Spitzer stemmed from an internal heater switching on for an hour to warm a battery. The engineers managed to cut the wobble in half while preserving the battery by reducing the heater to 30-minute cycles. Next, in September 2011, the engineers repurposed a “Peak-Up” camera, used during Spitzer’s early, cryogenic mission. The Peak-Up Camera can precisely place infrared light onto an exact part of a pixel in Spitzer’s infrared camera. Engineers also mapped an individual pixel for its “sweet spot” that returns the most stable observations.

    With these refinements in place, Spitzer could theoretically look for tiny brightness changes due to Sagittarius A* without having to isolate the object from its nearby stars. Because those neighboring stars do not vary much in brightness, any variations seen in the combined light from that region can be chalked up to activity by Sagittarius A*. Remarkably, Spitzer can detect a change of a few tenths of a percent in infrared light emanating from the Milky Way’s core.

    “When Sagittarius A* flares, it produces an increase in light in the infrared range. If the flare is bright enough, then Spitzer sees that as light poured on top of what’s coming at the telescope already,” said Gorjian.

    With a view undisturbed by Earth’s atmosphere and the ability to monitor Sagittarius A* for more than 20 hours straight, Spitzer is an important extension of ground-based infrared observations of the black hole.

    “With Spitzer, you can monitor longer, and that’s critical in determining what is causing the variability in Sagittarius A*,” said Hora.

    Spitzer’s upcoming observations this summer in tandem with Chandra will gather infrared and X-ray emission to probe material very close to the Sagittarius A* black hole itself, helping test models of what causes the flare. It’s a whole new science objective for Spitzer, which continues to surprise and delight so many years after its launch in the summer of 2003.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory located on the campus of the California Institute of Technology and part of NASA’s Infrared Processing and Analysis Center.

    NASA image

    NASA JPL Icon

     
  • richardmitnick 3:44 pm on June 14, 2016 Permalink | Reply
    Tags: , FU Orionis Gluttonous Star May Hold Clues to Planet Formation, , , NASA Spitzer   

    From JPL-Caltech: “Gluttonous Star May Hold Clues to Planet Formation” 

    NASA JPL Banner

    JPL-Caltech

    June 14, 2016
    Elizabeth Landau
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-354-6425
    elizabeth.landau@jpl.nasa.gov

    1
    The brightness of outbursting star FU Orionis has been slowly fading since its initial flare-up in 1936. Researchers found that it has dimmed by about 13 percent in short infrared wavelengths from 2004 (left) to 2016 (right). Credit: NASA/JPL-Caltech

    In 1936, the young star FU Orionis began gobbling material from its surrounding disk of gas and dust with a sudden voraciousness. During a three-month binge, as matter turned into energy, the star became 100 times brighter, heating the disk around it to temperatures of up to 12,000 degrees Fahrenheit (7,000 Kelvin). FU Orionis is still devouring gas to this day, although not as quickly.

    This brightening is the most extreme event of its kind that has been confirmed around a star the size of the sun, and may have implications for how stars and planets form. The intense baking of the star’s surrounding disk likely changed its chemistry, permanently altering material that could one day turn into planets.

    “By studying FU Orionis, we’re seeing the absolute baby years of a solar system,” said Joel Green, a project scientist at the Space Telescope Science Institute, Baltimore, Maryland. “Our own sun may have gone through a similar brightening, which would have been a crucial step in the formation of Earth and other planets in our solar system.”

    Visible light observations of FU Orionis, which is about 1,500 light-years away from Earth in the constellation Orion, have shown astronomers that the star’s extreme brightness began slowly fading after its initial 1936 burst. But Green and colleagues wanted to know more about the relationship between the star and surrounding disk. Is the star still gorging on it? Is its composition changing? When will the star’s brightness return to pre-outburst levels?

    To answer these questions, scientists needed to observe the star’s brightness at infrared wavelengths, which are longer than the human eye can see and provide temperature measurements.

    Green and his team compared infrared data obtained in 2016 using the Stratospheric Observatory for Infrared Astronomy, SOFIA, to observations made with NASA’s Spitzer Space Telescope in 2004.

    NASA/DLR SOFIA
    NASA/DLR SOFIA

    NASA/Spitzer Telescope
    NASA/Spitzer Telescope

    SOFIA, the world’s largest airborne observatory, is jointly operated by NASA and the German Aerospace Center and provides observations at wavelengths no longer attainable by Spitzer. The SOFIA data were taken using the FORCAST instrument (Faint Object infrared Camera for the SOFIA Telescope).

    NASA/SOFIA Forcast
    NASA/SOFIA Forcast

    “By combining data from the two telescopes collected over a 12-year interval, we were able to gain a unique perspective on the star’s behavior over time,” Green said. He presented the results at the American Astronomical Society meeting in San Diego, this week.

    Using these infrared observations and other historical data, researchers found that FU Orionis had continued its ravenous snacking after the initial brightening event: The star has eaten the equivalent of 18 Jupiters in the last 80 years.

    The recent measurements provided by SOFIA inform researchers that the total amount of visible and infrared light energy coming out of the FU Orionis system decreased by about 13 percent over the 12 years since the Spitzer observations. Researchers determined that this decrease is caused by dimming of the star at short infrared wavelengths, but not at longer wavelengths. That means up to 13 percent of the hottest material of the disk has disappeared, while colder material has stayed intact.

    “A decrease in the hottest gas means that the star is eating the innermost part of the disk, but the rest of the disk has essentially not changed in the last 12 years,” Green said. “This result is consistent with computer models, but for the first time we are able to confirm the theory with observations.”

    Astronomers predict, partly based on the new results, that FU Orionis will run out of hot material to nosh on within the next few hundred years. At that point, the star will return to the state it was in before the dramatic 1936 brightening event. Scientists are unsure what the star was like before or what set off the feeding frenzy.

    “The material falling into the star is like water from a hose that’s slowly being pinched off,” Green said. “Eventually the water will stop.”

    If our sun had a brightening event like FU Orionis did in 1936, this could explain why certain elements are more abundant on Mars than on Earth. A sudden 100-fold brightening would have altered the chemical composition of material close to the star, but not as much farther from it. Because Mars formed farther from the sun, its component material would not have been heated up as much as Earth’s was.

    At a few hundred thousand years old, FU Orionis is a toddler in the typical lifespan of a star. The 80 years of brightening and fading since 1936 represent only a tiny fraction of the star’s life so far, but these changes happened to occur at a time when astronomers could observe.

    “It’s amazing that an entire protoplanetary disk can change on such a short timescale, within a human lifetime,” said Luisa Rebull, study co-author and research scientist at the Infrared Processing and Analysis Center (IPAC), based at Caltech, Pasadena, California.

    Green plans to gain more insight into the FU Orionis feeding phenomenon with NASA’s James Webb Space Telescope, which will launch in 2018.

    NASA/ESA/CSA Webb Telescope annotated
    NASA/ESA/CSA Webb Telescope annotated

    SOFIA has mid-infrared high-resolution spectrometers and far-infrared science instrumentation that complement Webb’s planned near- and mid-infrared capabilities. Spitzer is expected to continue exploring the universe in infrared light, and enabling groundbreaking scientific investigations, into early 2019.

    NASA’s Jet Propulsion Laboratory, Pasadena, California, manages the Spitzer Space Telescope mission for NASA. Science operations are conducted at the Spitzer Science Center at Caltech. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. Data are archived at the Infrared Science Archive housed at IPAC at Caltech. Caltech manages JPL for NASA.

    SOFIA is a joint project of NASA and the German Aerospace Center (DLR). The aircraft is based at NASA Armstrong Flight Research Center’s facility in Palmdale, California. NASA’s Ames Research Center in Moffett Field, California, manages the SOFIA science and mission operations in cooperation with the Universities Space Research Association (USRA) headquartered in Columbia, Maryland, and the German SOFIA Institute (DSI) at the University of Stuttgart.

    For more information about Spitzer, visit:

    http://www.nasa.gov/spitzer

    http://spitzer.caltech.edu

    For more information about SOFIA, visit:

    http://www.nasa.gov/sofia

    http://www.dlr.de/en/sofia

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

    Caltech Logo
    jpl

    NASA image

     
c
Compose new post
j
Next post/Next comment
k
Previous post/Previous comment
r
Reply
e
Edit
o
Show/Hide comments
t
Go to top
l
Go to login
h
Show/Hide help
shift + esc
Cancel
%d bloggers like this: