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  • richardmitnick 6:43 am on July 24, 2015 Permalink | Reply
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    From Keck: “Found: Earth’s Closest Cousin Yet” 

    Keck Observatory

    Keck Observatory

    Keck Observatory

    July 23, 2015
    No Writer Credit

    1
    This artist’s concept compares Earth (left) to the new planet, called Kepler-452b, which is about 60 percent larger in diameter.
    Credit: NASA/JPL-Caltech/T. Pyle

    2
    This size and scale of the Kepler-452 system compared alongside the Kepler-186 system and the solar system. Kepler-186 is a miniature solar system that would fit entirely inside the orbit of Mercury. Credit: NASA/JPL-CalTech/R. Hurt

    The W. M. Keck Observatory has confirmed the first near-Earth-size planet in the “habitable zone” around a sun-like star. This discovery and the introduction of 11 other new small habitable zone candidate planets were originally made by NASA’s Kepler space telescopes and mark another milestone in the journey to finding another “Earth.”

    NASA Kepler Telescope
    Kepler

    “We can think of Kepler-452b as bigger, older cousin to Earth, providing an opportunity to understand and reflect upon Earth’s evolving environment,” said Jon Jenkins, Kepler data analysis lead at NASA’s Ames Research Center in Moffett Field, California, who led the team that discovered Kepler-452b. “It’s awe-inspiring to consider that this planet has spent 6 billion years in the habitable zone of its star; about 1.5 billion years longer than Earth. That’s substantial opportunity for life to arise, should all the necessary ingredients and conditions for life exist on this planet.”

    The data from Kepler suggested to the team there was a planet causing the light from it’s host star to dim as is orbited around it. The team then turned to ground-based observatories including the University of Texas at Austin’s McDonald Observatory, the Fred Lawrence Whipple Observatory on Mt. Hopkins, Arizona, and the world’s largest telescopes at Keck Observatory on Maunakea, Hawaii for confirmation.

    U Texas McDonald Observatory Campus
    University of Texas at Austin’s McDonald Observatory

    CfA Whipple Observatory
    CfA Fred Lawrence Whipple Observatory

    Specifically, the ten-meter Keck I telescope, fitted with the HIRES instrument was used to confirm the Kepler data as well as to more precisely determine the properties of the star, specifically its temperature, surface gravity and metallicity.

    Keck HIRES
    HIRES

    “These fundamental properties are used to determine the stellar mass and radius allowing for precise determination of the planet size,” said Howard Isaacson, researcher in the astronomy department at UC Berkeley and mamba of the discovery team. “With the precise stellar parameters from the HIRES spectrum, we can show that planet radius is closer to the size of the Earth, than say Neptune (~4x Earth’s radius). With a radius of 1.6 times the radius of the Earth, the chances of the planet having some sort of rocky surface is predicted to be ~50%. The Keck Observatory spectrum is also used to rule out false positive scenarios. Background stars can confuses the interpretation of the planet hypothesis, and the Keck Observatory spectrum shows that no such background stars are present.”

    The newly discovered Kepler-452b is the smallest planet to date discovered orbiting a sun-like star (G2-type star) in the habitable zone — the area around a star where liquid water could pool on the surface of an orbiting planet. The confirmation of Kepler-452b brings the total number of confirmed planets to 1,030.

    Kepler-452b is 60 percent larger than Earth and is considered a super-Earth-size planet. While its mass and composition are not yet determined, previous research suggests that planets the size of Kepler-452b have a good chance of being rocky.

    While Kepler-452b is larger than Earth, its 385-day orbit is only 5 percent longer. The planet is 5 percent farther from its parent star Kepler-452 than Earth is from the Sun. Kepler-452 is 6 billion years old, 1.5 billion years older than our sun, has the same temperature, and is 10 percent larger and 20 percent brighter.

    The Kepler-452 system is located 1,400 light-years away in the constellation Cygnus. The research paper reporting this finding has been accepted for publication in The Astronomical Journal.

    In addition to confirming Kepler-452b, the Kepler team has increased the number of new exoplanet candidates by 521 from their analysis of observations conducted from May 2009 to May 2013, raising the number of planet candidates detected by the Kepler mission to 4,696. Candidates require follow-up observations and analysis to verify they are actual planets.

    Twelve of the new planet candidates have diameters between one to two times that of Earth, and orbit in their star’s habitable zone. Of these, nine orbit stars that are similar to our sun in size and temperature. These candidates are likely targets for future observing runs at Keck Observatory for confirmation.

    “We’ve been able to fully automate our process of identifying planet candidates, which means we can finally assess every transit signal in the entire Kepler dataset quickly and uniformly,” said Jeff Coughlin, Kepler scientist at the SETI Institute in Mountain View, California, who led the analysis of a new candidate catalog. “This gives astronomers a statistically sound population of planet candidates to accurately determine the number of small, possibly rocky planets like Earth in our Milky Way galaxy.”

    These findings, presented in the seventh Kepler Candidate Catalog, will be submitted for publication in the Astrophysical Journal. These findings are derived from data publically available on the NASA Exoplanet Archive.

    HIRES (the High-Resolution Echelle Spectrometer) produces spectra of single objects at very high spectral resolution, yet covering a wide wavelength range. It does this by separating the light into many “stripes” of spectra stacked across a mosaic of three large CCD detectors. HIRES is famous for finding planets orbiting other stars. Astronomers also use HIRES to study distant galaxies and quasars, finding clues to the Big Bang. 


    See the full article here.

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    Mission
    To advance the frontiers of astronomy and share our discoveries with the world.

    The W. M. Keck Observatory operates the largest, most scientifically productive telescopes on Earth. The two, 10-meter optical/infrared telescopes on the summit of Mauna Kea on the Island of Hawaii feature a suite of advanced instruments including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectrometer and world-leading laser guide star adaptive optics systems. Keck Observatory is a private 501(c) 3 non-profit organization and a scientific partnership of the California Institute of Technology, the University of California and NASA.

    Today Keck Observatory is supported by both public funding sources and private philanthropy. As a 501(c)3, the organization is managed by the California Association for Research in Astronomy (CARA), whose Board of Directors includes representatives from the California Institute of Technology and the University of California, with liaisons to the board from NASA and the Keck Foundation.
    Keck UCal

    Keck NASA

    Keck Caltech

     
  • richardmitnick 11:40 am on July 23, 2015 Permalink | Reply
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    From NASA Kepler: “NASA’s Kepler Mission Discovers Bigger, Older Cousin to Earth” 

    NASA Kepler Logo

    NASA Kepler Telescope
    NASA/Kepler

    July 23, 2015

    1
    This artist’s concept compares Earth (left) to the new planet, called Kepler-452b, which is about 60 percent larger in diameter. Credits: NASA/JPL-Caltech/T. Pyle

    2
    This size and scale of the Kepler-452 system compared alongside the Kepler-186 system and the solar system. Kepler-186 is a miniature solar system that would fit entirely inside the orbit of Mercury. Credits: NASA/JPL-CalTech/R. Hurt

    NASA’s Kepler mission has confirmed the first near-Earth-size planet in the “habitable zone” around a sun-like star. This discovery and the introduction of 11 other new small habitable zone candidate planets mark another milestone in the journey to finding another “Earth.”

    The newly discovered Kepler-452b is the smallest planet to date discovered orbiting in the habitable zone — the area around a star where liquid water could pool on the surface of an orbiting planet — of a G2-type star, like our sun. The confirmation of Kepler-452b brings the total number of confirmed planets to 1,030.

    “On the 20th anniversary year of the discovery that proved other suns host planets, the Kepler exoplanet explorer has discovered a planet and star which most closely resemble the Earth and our Sun,” said John Grunsfeld, associate administrator of NASA’s Science Mission Directorate at the agency’s headquarters in Washington. “This exciting result brings us one step closer to finding an Earth 2.0.”

    Kepler-452b is 60 percent larger in diameter than Earth and is considered a super-Earth-size planet. While its mass and composition are not yet determined, previous research suggests that planets the size of Kepler-452b have a good chance of being rocky.

    While Kepler-452b is larger than Earth, its 385-day orbit is only 5 percent longer. The planet is 5 percent farther from its parent star Kepler-452 than Earth is from the Sun. Kepler-452 is 6 billion years old, 1.5 billion years older than our sun, has the same temperature, and is 20 percent brighter and has a diameter 10 percent larger.

    “We can think of Kepler-452b as an older, bigger cousin to Earth, providing an opportunity to understand and reflect upon Earth’s evolving environment,” said Jon Jenkins, Kepler data analysis lead at NASA’s Ames Research Center in Moffett Field, California, who led the team that discovered Kepler-452b. “It’s awe-inspiring to consider that this planet has spent 6 billion years in the habitable zone of its star; longer than Earth. That’s substantial opportunity for life to arise, should all the necessary ingredients and conditions for life exist on this planet.”

    To help confirm the finding and better determine the properties of the Kepler-452 system, the team conducted ground-based observations at the University of Texas at Austin’s McDonald Observatory, the Fred Lawrence Whipple Observatory on Mt. Hopkins, Arizona, and the W. M. Keck Observatory atop Mauna Kea in Hawaii. These measurements were key for the researchers to confirm the planetary nature of Kepler-452b, to refine the size and brightness of its host star and to better pin down the size of the planet and its orbit.

    U Texas McDonald Observatory Campus
    U Texas McDonald Observatory

    CfA Whipple Observatory
    CfA Whipple Observatory

    Keck Observatory
    Keck Observatory

    The Kepler-452 system is located 1,400 light-years away in the constellation Cygnus. The research paper reporting this finding has been accepted for publication in The Astronomical Journal.

    In addition to confirming Kepler-452b, the Kepler team has increased the number of new exoplanet candidates by 521 from their analysis of observations conducted from May 2009 to May 2013, raising the number of planet candidates detected by the Kepler mission to 4,696. Candidates require follow-up observations and analysis to verify they are actual planets.

    Twelve of the new planet candidates have diameters between one to two times that of Earth, and orbit in their star’s habitable zone. Of these, nine orbit stars that are similar to our sun in size and temperature.

    “We’ve been able to fully automate our process of identifying planet candidates, which means we can finally assess every transit signal in the entire Kepler dataset quickly and uniformly,” said Jeff Coughlin, Kepler scientist at the SETI Institute in Mountain View, California, who led the analysis of a new candidate catalog. “This gives astronomers a statistically sound population of planet candidates to accurately determine the number of small, possibly rocky planets like Earth in our Milky Way galaxy.”

    These findings, presented in the seventh Kepler Candidate Catalog, will be submitted for publication in the Astrophysical Journal. These findings are derived from data publically available on the NASA Exoplanet Archive.

    Scientists now are producing the last catalog based on the original Kepler mission’s four-year data set. The final analysis will be conducted using sophisticated software that is increasingly sensitive to the tiny telltale signatures of Earth-size planets.

    Ames manages the Kepler and K2 missions for NASA’s Science Mission Directorate. NASA’s Jet Propulsion Laboratory in Pasadena, California, managed Kepler mission development. Ball Aerospace & Technologies Corporation operates the flight system with support from the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder.

    For more information about the Kepler mission, visit:

    http://www.nasa.gov/kepler

    See the full article here.

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    The Kepler Mission, NASA Discovery mission #10, is specifically designed to survey our region of the Milky Way galaxy to discover hundreds of Earth-size and smaller planets in or near the habitable zone→ and determine the fraction of the hundreds of billions of stars in our galaxy that might have such planets.
    The operations phase of the Kepler mission is managed for NASA by the Ames Research Center, Moffett Field, CA. NASA’s Jet Propulsion Laboratory (JPL), Pasadena, CA, managed the mission through development, launch and the start of science operations. Dr. William Borucki of NASA Ames is the mission’s Science Principal Investigator. Ball Aerospace and Technologies Corp., Boulder, CO, developed the Kepler flight system.

    In October 2009, oversight of the Kepler project was transferred from the Discovery Program at NASA’s Marshall Space Flight Center, Huntsville, AL, to the Exoplanet Exploration Program at JPL

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  • richardmitnick 8:56 am on July 23, 2015 Permalink | Reply
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    From MIT: “New technique allows analysis of clouds around exoplanets” 


    MIT News

    March 3, 2015
    Helen Knight

    Team describes use of method to determine properties of clouds surrounding the exoplanet Kepler-7b.

    1
    Analysis of data from the Kepler space telescope has shown that roughly half of the dayside of the exoplanet Kepler-7b is covered by a large cloud mass. Statistical comparison of more than 1,000 atmospheric models show that these clouds are most likely made of Enstatite, a common Earth mineral that is in vapor form at the extreme temperature on Kepler-7b. These models varied the altitude, condensation, particle size, and chemical composition of the clouds to find the right reflectivity and color properties to match the observed signal from the exoplanet. Courtesy of NASA (edited by Jose-Luis Olivares/MIT)

    Meteorologists sometimes struggle to accurately predict the weather here on Earth, but now we can find out how cloudy it is on planets outside our solar system, thanks to researchers at MIT.

    In a paper to be published in the Astrophysical Journal, researchers in the Department of Earth, Atmospheric, and Planetary Sciences (EAPS) at MIT describe a technique that analyzes data from NASA’s Kepler space observatory to determine the types of clouds on planets that orbit other stars, known as exoplanets.

    NASA Kepler Telescope
    NASA/Kepler

    The team, led by Kerri Cahoy, an assistant professor of aeronautics and astronautics at MIT, has already used the method to determine the properties of clouds on the exoplanet Kepler-7b. The planet is known as a “hot Jupiter,” as temperatures in its atmosphere hover at around 1,700 kelvins.

    NASA’s Kepler spacecraft was designed to search for Earth-like planets orbiting other stars. It was pointed at a fixed patch of space, constantly monitoring the brightness of 145,000 stars. An orbiting exoplanet crossing in front of one of these stars causes a temporary dimming of this brightness, allowing researchers to detect its presence.

    Researchers have previously shown that by studying the variations in the amount of light coming from these star systems as a planet transits, or crosses in front or behind them, they can detect the presence of clouds in that planet’s atmosphere. That is because particles within the clouds will scatter different wavelengths of light.

    Modeling cloud formation

    To find out if this data could be used to determine the composition of these clouds, the MIT researchers studied the light signal from Kepler-7b. They used models of the temperature and pressure of the planet’s atmosphere to determine how different types of clouds would form within it, says lead author Matthew Webber, a graduate student in Cahoy’s group at MIT.

    “We then used those cloud models to determine how light would reflect off the atmosphere of the planet [for each type of cloud], and tried to match these possibilities to the actual observations from the Kepler mission itself,” Webber says. “So we ran a large set of models, to see which models fit best statistically to the observations.”

    By working backward in this way, they were able to match the Kepler spacecraft data to a type of cloud made out of vaporized silicates and magnesium. The extremely high temperatures in the Kepler-7b atmosphere mean that some minerals that commonly exist as rocks on Earth’s surface instead exist as vapors high up in the planet’s atmosphere. These mineral vapors form small cloud particles as they cool and condense.

    Kepler-7b is a tidally locked planet, meaning it always shows the same face to its star — just as the moon does to Earth. As a result, around half of the planet’s day side — that which constantly faces the star — is covered by these magnesium silicate clouds, the team found.

    “We are really doing nothing more complicated than putting a telescope into space and staring at a star with a camera,” Cahoy says. “Then we can use what we know about the universe, in terms of temperatures and pressures, how things mix, how they stratify in an atmosphere, to try to figure out what mix of things would be causing the observations that we’re seeing from these very basic instruments,” she says.

    A clue on exoplanet atmospheres

    Understanding the properties of the clouds on Kepler-7b, such as their mineral composition and average particle size, tells us a lot about the underlying physical nature of the planet’s atmosphere, says team member Nikole Lewis, a postdoc in EAPS. What’s more, the method could be used to study the properties of clouds on different types of planet, Lewis says: “It’s one of the few methods out there that can help you determine if a planet even has an atmosphere, for example.”

    A planet’s cloud coverage and composition also has a significant impact on how much of the energy from its star it will reflect, which in turn affects its climate and ultimately its habitability, Lewis says. “So right now we are looking at these big gas-giant planets because they give us a stronger signal,” she says. “But the same methodology could be applied to smaller planets, to help us determine if a planet is habitable or not.”

    The researchers hope to use the method to analyze data from NASA’s follow-up to the Kepler mission, known as K2, which began studying different patches of space last June. They also hope to use it on data from MIT’s planned Transiting Exoplanet Survey Satellite (TESS) mission, says Cahoy.

    NASA TESS
    NASA/TESS

    “TESS is the follow-up to Kepler, led by principal investigator George Ricker, a senior research scientist in the MIT Kavli Institute for Astrophysics and Space Research. It will essentially be taking similar measurements to Kepler, but of different types of stars,” Cahoy says. “Kepler was tasked with staring at one group of stars, but there are a lot of stars, and TESS is going to be sampling the brightest stars across the whole sky,” she says.

    This paper is the first to take circulation models including clouds and compare them with the observed distribution of clouds on Kepler-7b, says Heather Knutson, an assistant professor of planetary science at Caltech who was not involved in the research.

    “Their models indicate that the clouds on this planet are most likely made from liquid rock,” Knutson says. “This may sound exotic, but this planet is a roasting hot gas-giant planet orbiting very close to its host star, and we should expect that it might look quite different than our own Jupiter.”

    See the full article here.

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  • richardmitnick 9:04 am on July 16, 2015 Permalink | Reply
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    From space.com: “Ingredients for Earth-Like Planets Are Found All Around the Milky Way” 

    space-dot-com logo

    SPACE.com

    July 10, 2015
    Elizabeth Howell

    The building blocks to create another Earth are found at solar systems across our Milky Way galaxy, a new study reveals.

    By saying that carbon, oxygen, magnesium and silicon are in rocky planets everywhere, this new study contradicts previous research that’s said only some rocky planets have this recipe. Previously, scientists said there were three kinds of rocky planets: those similar to Earth, those that had more carbon, and some that had a lot more silicon than magnesium.

    “The ratio of elements on Earth has led to the chemical conditions ‘just right’ for life,” said lead researcher Brad Gibson, an astrophysicist at the University of Hull in the United Kingdom. “Too much magnesium or too little silicon, and your planet ends up having the wrong balance between minerals to form the type of rocks that make up the Earth’s crust,” Gibson added. “Too much carbon, and your rocky planet might turn out to be more like the graphite in your pencil than the surface of a planet like the Earth.”

    The new results come from a simulation of how the Milky Way formed. While Gibson said he was worried at first that the model was wrong, he added that it predicted different parts of our galaxy correctly — such as how frequently stars formed and died.


    Download is available at video

    The researchers also examined observations and found uncertainties concerning how many rocky-planet systems had recipes similar to Earth’s. “Removing these [uncertainties],” Gibson said, “observations agreed with our predictions that the same elemental building blocks are found in every exoplanet system, wherever it is in the galaxy.”

    Specifically, the uncertainties happened because observations tend to come from large planets that are orbiting bright stars, which are easier to see from Earth. This creates uncertainties of 10 percent to 20 percent, the researchers said.

    Also, oxygen and nickel spectra are hard to see from a distance, which adds to the uncertainty. Newer techniques will make these observations more accurate, the researchers added.

    The research was presented Wednesday (July 8) at the National Astronomy Meeting in Llandudno, Wales.

    See the full article here.

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  • richardmitnick 1:39 pm on May 1, 2015 Permalink | Reply
    Tags: , , Exoplanets, Twinkle   

    From Twinkle: “A British Space Mission to Explore Faraway Worlds” 

    1

    Twinkle is a small, low-cost mission that will use spectroscopy to decode the light from hundreds of extrasolar planets. Twinkle will be able to reveal, for the first time, the chemical composition, weather and history of worlds orbiting distant stars. The Twinkle satellite will be built in the UK and launched into a low-Earth orbit within 3 to 4 years, using a platform designed by Surrey Satellite Technology Ltd and instrumentation led by UCL.

    Follow the mission on twitter:
    @twinkle_mission

    The mission web site is here.

     
  • richardmitnick 3:39 pm on April 21, 2015 Permalink | Reply
    Tags: , , Exoplanets, NASA NExSS,   

    From Yale: “Yale joins new NASA team searching for life outside the solar system” 

    Yale University bloc

    Yale University

    April 21, 2015
    Jim Shelton

    1
    Artist’s conception of Kepler-186f, the first validated Earth-size planet to orbit a distant star in the habitable zone.

    2
    The search for life beyond our solar system requires unprecedented cooperation across scientific disciplines. NASA’s NExSS collaboration includes those who study Earth as a life-bearing planet (lower right), those researching the diversity of solar system planets (left), and those on the new frontier, discovering worlds orbiting other stars in the galaxy (upper right).
    Credits: NASA

    NASA is enlisting teams of scientists around the nation, including a group from Yale, to collaborate on a new approach for finding life on planets outside our solar system.

    The joint effort is called Nexus for Exoplanet System Science (NExSS), and it will create a “virtual institute” of scientists from 10 universities, three NASA centers, and two research institutes. NASA selected teams based on proposals from across NASA’s Science Mission Directorate.

    Yale astronomy professor Debra Fischer will lead a team that is building new spectrometers with the stability and precision to detect Earth-like planets orbiting nearby stars. A critical part of the team’s work involves new statistical techniques to distinguish “noise” — velocities in the photospheres of the stars — from the reflex velocities induced by planets.

    Fischer’s team also will continue to enlist amateur astronomers to search NASA’s Kepler public archive data for exoplanets, which are planets orbiting around other stars. Fischer has been at the forefront of citizen science efforts to search for exoplanets via the Planet Hunters program. Citizen scientists have found more than 100 transiting exoplanets not previously detected. Many of these planets orbit in the habitable zones of their host stars.

    Fischer’s team also is analyzing the planet occurrence rates for different types of stars.

    “NExSS is building collaboration and open-sourcing of ideas in ways that have been tried and true in competitive businesses,” Fischer said. “This signals a new era where we spend more time problem-solving and team-building than competing and excluding our colleagues. We have heard from all of the founding partners about their research, and we’ve brainstormed about how our related skills and expertise might enrich their science. It’s a win-win for science and humanity.”

    Since the launch of NASA’s Kepler space telescope six years ago, more than 1,800 exoplanets have been confirmed.

    NASA Kepler Telescope
    Kepler

    There are thousands more exoplanet candidates waiting for confirmation.

    In order to determine the habitability of these planets and look for signs of life on them, NExSS will coordinate scientific research into the various components of exoplanets. It’s a “system science” approach to understanding how biology interacts with the atmosphere, geology, oceans, and interior of a planet, and how the host star affects these interactions.

    NExSS will draw from the scientific expertise in each division of NASA’s Science Mission Directorate. Earth scientists will develop a systems science approach by studying our home planet; planetary scientists will look at other planets in our solar system; heliophysicists will study how the Sun interacts with orbiting planets; and astrophysicists will provide data on exoplanets and host stars.

    “This interdisciplinary endeavor connects top research teams and provides a synthesized approach in the search for planets with the greatest potential for signs of life,” said Jim Green, NASA’s director of planetary science. “The hunt for exoplanets is not only a priority for astronomers, it’s of keen interest to planetary and climate scientists as well.”

    NExSS will be led by scientists from the NASA Ames Research Center, the NASA Exoplanet Science Institute at the California Institute of Technology, and the NASA Goddard Institute for Space Studies.

    See the full article here.

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    Yale University Campus

    Yale University comprises three major academic components: Yale College (the undergraduate program), the Graduate School of Arts and Sciences, and the professional schools. In addition, Yale encompasses a wide array of centers and programs, libraries, museums, and administrative support offices. Approximately 11,250 students attend Yale.

     
  • richardmitnick 8:07 am on March 20, 2015 Permalink | Reply
    Tags: , , , Exoplanets   

    From Science 2.0- “ESA’s CHEOPS Satellite: The Pharaoh of Exoplanet Hunting” 

    Science 2.0 bloc

    Science 2.0

    March 19th 2015
    Tomasz Nowakowski

    ESA CHEOPS
    CHEOPS

    Just like the Pharaoh Cheops, who ruled the ancient Old Kingdom of Egypt, ESA’s CHaracterising ExOPlanet Satellite (CHEOPS) could be someday ruling in the field of exoplanet hunting.

    It will be the first mission dedicated to search for transits by means of ultrahigh precision photometry on bright stars already known to host planets. “CHEOPS looks at stars that are already known to host planets and attempts to observe transits. I say attempts because its main targets are planets that have been discovered through Doppler techniques,” Don Pollacco of the University of Warwick, UK spokesperson for the CHEOPS mission, told me.

    Large ground-based high-precision Doppler spectroscopic surveys carried out during the last years have identified hundreds of stars hosting planets in the super-Earth to Neptune mass range and will continue to do so into the foreseeable future. The characteristics of these stars and the knowledge of the planet ephemerids make them ideal targets for precision photometric measurements from space. CHEOPS will be the only facility able to follow-up all these targets for precise radius measurements.

    “Doppler surveys have been going on for some time and have found a significant fraction of multiple and duper earth massed planets, well before Kepler did this.

    NASA Kepler Telescope
    NASA/Kepler

    Some proportions of these are expected to transit their host star – maybe 10%. As you know when these transits are meant to occur you can look at these targets specifically at that time and avoid wasting too much time,” Pollacco said. “10% doesn’t sound much but these will be important targets in that they’ll be bright, already have Doppler curves and hence able to determine their densities. It’s likely that a few tens of planets maybe discovered this way, there’s a handful from Kepler if that.”

    Knowing where to look and at what time to observe, makes CHEOPS the most efficient instrument to search for shallow transits.

    With an accurate knowledge of masses and radii for an unprecedented sample of planets, CHEOPS will set new constraints on the structure and hence on the formation and evolution of planets in this mass range.

    “By knowing where to look and at what time, CHEOPS is the most efficient instrument to detect shallow transits. It will significantly increase the sample of exoplanets for which we know both mass and radius, providing new insights and constraints on formation models,” said Willy Benz from the University of Bern, Switzerland, the Principal Investigator for CHEOPS.

    ESA is the mission architect for CHEOPS, responsible for spacecraft development and launch, and for the interface with the science community during science operations in orbit.

    CHEOPS is the first of the small-size (S class) missions of ESA, and was selected from 26 other proposed missions. These missions are designed to take full advantage of known technologies. They should be low cost and rapidly developed missions, in order to offer greater flexibility in response to new ideas from the scientific community.

    “The need for a pointed space telescope to do high precision transit observations, has been known for a while and there were various concepts already explored. In the UK we had something nicknamed “BEE” which was meant to follow up SuperWASP discoveries. CHEOPS was already under development when the first S mission opportunity arose and so it was in good shape to be submitted to this,” Pollacco revealed. “The S missions were meant to be opportunities for smaller ESA members to demonstrate their space industries and take the lead so CHEOPS was extremely well placed.”

    Pollacco admitted that CHEOPS is different to NASA exoplanet hunting missions like Kepler spacecraft or Transiting Exoplanet Survey Satellite (TESS).

    NASA TESS
    NASA/TESS

    These are survey missions that look at large areas of the sky and discover transiting planets, while CHEOPS looks at stars that are already known to have orbiting planets.

    “For TESS it really remains to be seen what can be achieved but in any case CHEOPS with its superior accuracy will produce more accurate transits, and hence densities of Doppler confirmed TESS planets,” he said. “A second aim for CHEOPS is to follow up transits discovered from other surveys, like the Next-Generation Transit Survey (NGTS), again because of its superior accuracy.”

    The satellite will fly at an altitude of between 650 and 800km, in a dusk-dawn helio-synchronous orbit, and will have a design lifetime of 3.5 years. “For CHEOPS scheduling will be important given its low orbit meaning that it can’t stare long in many directions,” Pollacco added.

    CHEOPS should be able to cover at least 50% of the whole sky for a minimum total duration of 50 days of observation per year and per target. The observation may be interrupted up to 50% (goal would be 20%) of the satellite orbital duration (Earth eclipse, Sun, etc.).

    The Prime contractor for CHEOPS is Airbus Defence and Space, Spain. The spacecraft is based on the Airbus Defence and Space AstroBus family of low cost satellite platforms (following on from e.g. Spot 6&7, KazEOSat-1), and the ninth for an ESA program following on from Sentinel 5 Precursor and the MetOp Second Generation satellites.

    CHEOPS mission will be implemented in partnership with Switzerland, through the Swiss Space Office (SSO), a division of the Swiss State Secretariat for Education, Research and Innovation (SERI). The University of Bern leads the consortium of 11 ESA Member States contributing to the mission and represented in the CHEOPS Science Team.

    The science instrument is led by the University of Bern, with important contributions from Italy, Germany, Austria, and Belgium. Other contributions to the science instrument in the form of hardware, or in the science operations and exploitation, are provided by the United Kingdom, France, Hungary, Portugal and Sweden. The Mission Operations Centre is under the responsibility of Spain, while the Science Operations Centre is located at the University of Geneva, Switzerland.

    “For historical reasons UK industry is not playing a major role in CHEOPS. In the original baseline we expected the UK to run the mission operations but for a number of reasons that never happened,” Pollacco said. “However we retain some software contributions and so some elements of the UK exoplanet community have stayed in touch with the mission. It’s worth noting that Didier Queloz [Swiss astronomer] moved to Cambridge from Geneva over the last couple of years but retains a significant post at Geneva specifically for CHEOPS work. In other countries, e.g. Germany, Italy, there is a far larger involvement, both technically and industrially, although the Swiss remain by far the largest contributor, as it should be.”

    CHEOPS will most likely be launched into space by a Soyuz or Vega launcher from Kourou spaceport in French Guiana in December 2017.

    See the full article here.

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  • richardmitnick 9:31 am on March 18, 2015 Permalink | Reply
    Tags: , , Exoplanets, , Niels Bohr Institute   

    From Niels Bohr Institute: “Planets in the habitable zone around most stars, calculate researchers” 

    Niels Bohr Institute bloc

    Niels Bohr Institute

    18 March 2015
    Gertie Skaarup
    skaarup@nbi.dk

    Habitable planets

    Astronomers have discovered thousands of exoplanets in our galaxy, the Milky Way, using the Kepler satellite and many of them have multiple planets orbiting the host star.

    NASA Kepler Telescope
    NASA/Kepler

    By analysing these planetary systems, researchers from the Australian National University and the Niels Bohr Institute in Copenhagen have calculated the probability for the number of stars in the Milky Way that might have planets in the habitable zone. The calculations show that billions of the stars in the Milky Way will have one to three planets in the habitable zone, where there is the potential for liquid water and where life could exist. The results are published in the scientific journal, Monthly Notices of the Royal Astronomical Society.

    1
    Planets outside our solar system are called exoplanets. The Kepler satellite observes exoplanets by measuring the light curve of a star. When a planet moves in front of the star there is a small dip in brightness. If this little dip in brightness occurs regularly, there might be a planet orbiting the star and obscuring its light.

    Using NASA’s Kepler satellite, astronomers have found about 1,000 planets around stars in the Milky Way and they have also found about 3,000 other potential planets. Many of the stars have planetary systems with 2-6 planets, but the stars could very well have more planets than those observable with the Kepler satellite, which is best suited for finding large planets that orbit relatively close to their stars.

    Planets that orbit close to their stars would be too scorching hot to have life, so to find out if such planetary systems might also have planets in the habitable zone with the potential for liquid water and life, a group of researchers from the Australian National University and the Niels Bohr Institute at the University of Copenhagen made calculations based on a new version of a 250-year-old method called the Titius-Bode law.

    2
    Light curves of the five planets orbiting the star Kepler-62. The dip in the light curve occur when the planet moves in front of the host star, thereby dimming the light of the star. The dip in the light curve is proportional to the size of the planet. The two light curves at the bottom of the plot are of planets in the habitable zone.

    Calculating planetary positions

    The Titius-Bode law was formulated around 1770 and correctly calculated the position of Uranus before it was even discovered. The law states that there is a certain ratio between the orbital periods of planets in a solar system. So the ratio between the orbital period of the first and second planet is the same as the ratio between the second and the third planet and so on. Therefore, if you knew how long it takes for some of the planets to orbit around the Sun/star, you can calculate how long it takes for the other planets to orbit and can thus calculate their position in the planetary system. You can also calculate if a planet is ‘missing’ in the sequence.

    “We decided to use this method to calculate the potential planetary positions in 151 planetary systems, where the Kepler satellite had found between 3 and 6 planets. In 124 of the planetary systems, the Titius-Bode law fit with the position of the planets as good as or better than our own solar system. Using T-B’s law we tried to predict where there could be more planets further out in the planetary systems. But we only made calculations for planets where there is a good chance that you can see them with the Kepler satellite,” explains Steffen Kjær Jacobsen, PhD student in the research group Astrophysics and Planetary Science at the Niels Bohr Institute at the University of Copenhagen.

    In 27 of the 151 planetary systems, the planets that had been observed did not fit the T-B law at first glance. They then tried to place planets into the ‘pattern’ for where planets should be located. Then they added the planets that seemed to be missing between the already known planets and also added one extra planet in the system beyond the outermost known planet. In this way, they predicted a total of 228 planets in the 151 planetary systems.

    2
    The illustration shows the habitable zone for different types of stars. The distance to the habitable zone is dependent on how big and bright the star is. The green area is the habitable zone (HZ), where liquid water can exist on a planet’s surface. The red area is too hot for liquid water on the planetary surface and the blue area is too cold for liquid water on the planetary surface. (Credit: NASA, Kepler)

    “We then made a priority list with 77 planets in 40 planetary systems to focus on because they have a high probability of making a transit, so you can see them with Kepler. We have encouraged other researchers to look for these. If they are found, it is an indication that the theory stands up,” explains Steffen Kjær Jacobsen.

    Planets in the habitable zone

    Planets that orbit very close around a star are too scorching hot to have liquid water and life and planets that are far from the star would be too deep-frozen, but the intermediate habitable zone, where there is the potential for liquid water and life, is not a fixed distance. The habitable zone for a planetary system will be different from star to star, depending on how big and bright the star is.

    The researchers evaluated the number of planets in the habitable zone based on the extra planets that were added to the 151 planetary systems according to the Titius-Bode law. The result was 1-3 planets in the habitable zone for each planetary system.

    4
    Exoplanetary systems where the previously known planets are marked with blue dots, while the red dots show the planets predicted by the Titius-Bode law on the composition of planetary systems. 124 planetary systems in the survey – based on data from the Kepler satellite, fit with this formula.

    Out of the 151 planetary systems, they now made an additional check on 31 planetary systems where they had already found planets in the habitable zone or where only a single extra planet was needed to meet the requirements.

    “In these 31 planetary systems that were close to the habitable zone, our calculations showed that there was an average of two planets in the habitable zone. According to the statistics and the indications we have, a good share of the planets in the habitable zone will be solid planets where there might be liquid water and where life could exist,” explains Steffen Kjær Jacobsen.

    If you then take the calculations further out into space, it would mean that just in our galaxy, the Milky Way, there could be billions of stars with planets in the habitable zone, where there could be liquid water and where life could exist.

    He explains that what they now want to do is encourage other researchers to look at the Kepler data again for the 40 planetary systems that they have predicted should be well placed to be observed with the Kepler satellite.

    Out of the 151 planetary systems, they now made an additional check on 31 planetary systems where they had already found planets in the habitable zone or where only a single extra planet was needed to meet the requirements.

    “In these 31 planetary systems that were close to the habitable zone, our calculations showed that there was an average of two planets in the habitable zone. According to the statistics and the indications we have, a good share of the planets in the habitable zone will be solid planets where there might be liquid water and where life could exist,” explains Steffen Kjær Jacobsen.

    If you then take the calculations further out into space, it would mean that just in our galaxy, the Milky Way, there could be billions of stars with planets in the habitable zone, where there could be liquid water and where life could exist.

    He explains that what they now want to do is encourage other researchers to look at the Kepler data again for the 40 planetary systems that they have predicted should be well placed to be observed with the Kepler satellite.

    Article in Monthly Notices of the Royal Astronomical Society

    See the full article here.

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    Niels Bohr Institute Campus

    The Niels Bohr Institute (Danish: Niels Bohr Institutet) is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics.

    The Institute was founded in 1921, as the Institute for Theoretical Physics of the University of Copenhagen, by the Danish theoretical physicist Niels Bohr, who had been on the staff of the University of Copenhagen since 1914, and who had been lobbying for its creation since his appointment as professor in 1916. On the 80th anniversary of Niels Bohr’s birth – October 7, 1965 – the Institute officially became The Niels Bohr Institute.[1] Much of its original funding came from the charitable foundation of the Carlsberg brewery, and later from the Rockefeller Foundation.[2]

    During the 1920s, and 1930s, the Institute was the center of the developing disciplines of atomic physics and quantum physics. Physicists from across Europe (and sometimes further abroad) often visited the Institute to confer with Bohr on new theories and discoveries. The Copenhagen interpretation of quantum mechanics is named after work done at the Institute during this time.

    On January 1, 1993 the institute was fused with the Astronomic Observatory, the Ørsted Laboratory and the Geophysical Institute. The new resulting institute retained the name Niels Bohr Institute.

     
  • richardmitnick 8:11 am on March 10, 2015 Permalink | Reply
    Tags: , , , Exoplanets   

    From Discovery: “‘Habitable’ Super-Earth Might Exist After All” 

    Discovery News
    Discovery News

    Mar 9, 2015
    Ian O’Neill

    1
    Possible image of Gliese 581d, a controversial exoplanet that may exist only 20 light-years from Earth.

    Despite having discovered nearly 2,000 alien worlds beyond our solar system, the profound search for exoplanets — a quest focused on finding a true Earth analog — is still in its infancy. It is therefore not surprising that some exoplanet discoveries aren’t discoveries at all; they are in fact just noise in astronomical data sets.

    But when disproving the existence of extrasolar planets that have some characteristics similar to Earth, we need to take more care during the analyses of these data, argue astronomers from Queen Mary, University of London and the University of Hertfordshire.

    In a paper published by the journal Science last week, the researchers focus on the first exoplanet discovered to orbit a nearby star within its habitable zone.

    Revealed in 2009, Gliese 581d hit the headlines as a “super-Earth” that had the potential to support liquid water on its possibly rocky surface. With a mass of around 7 times that of Earth, Gliese 581d would be twice as big with a surface gravity around twice that of Earth. Though extreme, it’s not such a stretch of the imagination that such a world, if it is proven to possess an atmosphere and liquid ocean, that life could take hold.

    And the hunt for life-giving alien worlds is, of course, the central motivation for exoplanetary studies.

    But the exoplanet signal has been called into doubt.

    3
    Gliese 581d’s star, Gliese 581, is a small red dwarf around 20 light-years away.
    ESO/Digitized Sky Survey photo.

    Red dwarfs are known to be tempestuous little stars, often generating violent flaring outbursts and peppered in dark features called starspots. To detect the exoplanet, astronomers measured the very slight frequency shift (Doppler shift) of light from the star — as the world orbits, it exerts a tiny gravitational “tug”, causing the star to wobble. When this periodic wobble is detected, through an astronomical technique known as the “radial velocity method,” a planet may be revealed.

    Last year, however, in a publication headed by astronomers at The Pennsylvania State University, astronomers pointed to the star’s activity as an interfering factor that may have imitated the signal from an orbiting planet when in fact, it was just noisy data.

    But this conclusion was premature, argues Guillem Anglada-Escudé, of Queen Mary, saying that “one needs to be more careful with these kind of claims.”

    “The existence, or not, of GJ 581d is significant because it was the first Earth-like planet discovered in the ‘Goldilocks’-zone around another star and it is a benchmark case for the Doppler technique,” said Anglada-Escudé in a university press release. “There are always discussions among scientists about the ways we interpret data but I’m confident that GJ 581d has been in orbit around Gliese 581 all along. In any case, the strength of their statement was way too strong. If the way to treat the data had been right, then some planet search projects at several ground-based observatories would need to be significantly revised as they are all aiming to detect even smaller planets.”

    The upshot is that this new paper challenges the statistical technique used in 2014 to account for the signal being stellar noise — focusing around the presence of starspots in Gliese 581′s photosphere.

    Gliese 581d isn’t the only possible exoplanet that exists around that star — controversy has also been created by another, potentially habitable exoplanet called Gliese 581g. Also originally detected through the wobble of the star, this 3-4 Earth mass world was found to also be in orbit within the habitable zone. But its existence has been the focus of several studies supporting and discounting its presence. Gliese 581 is also home to 3 other confirmed exoplanets, Gliese 581e, b and c.

    Currently, observational data suggests Gliese 581g was just noise, but as the continuing debate about Gliese 581d is proving, this is one controversy that will likely keep on rumbling in the scientific journals for some time.

    See the full article here.

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  • richardmitnick 7:33 pm on March 3, 2015 Permalink | Reply
    Tags: , Exoplanets, , Frank Drake, ,   

    From Space.com: “The Father of SETI: Q&A with Astronomer Frank Drake” 

    space-dot-com logo

    SPACE.com

    February 26, 2015
    Leonard David

    Arecibo Observatory

    Detecting signals from intelligent aliens is a lifelong quest of noted astronomer Frank Drake. He conducted the first modern search for extraterrestrial intelligence (SETI) experiment in 1960. More than five decades later, the hunt remains front-and-center for the scientist.

    5
    Frank Drake

    Drake also devised a thought experiment in 1961 to identify specific factors believed to play a role in the development of civilizations in our galaxy. This experiment took the form of an equation that researchers have used to estimate the possible number of alien civilizations — the famous Drake Equation.

    The Drake equation is:

    N = R*. fp. ne. fl. fi. fc. L

    where:

    N = the number of civilizations in our galaxy with which radio-communication might be possible (i.e. which are on our current past light cone);

    and

    R* = the average rate of star formation in our galaxy
    fp = the fraction of those stars that have planets
    ne = the average number of planets that can potentially support life per star that has planets
    fl = the fraction of planets that could support life that actually develop life at some point
    fi = the fraction of planets with life that actually go on to develop intelligent life (civilizations)
    fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space
    L = the length of time for which such civilizations release detectable signals into space

    Drake constructed the “Arecibo Message” of 1974 — the first interstellar message transmitted via radio waves from Earth for the benefit of any extraterrestrial civilization that may be listening.

    The message consists of seven parts that encode the following (from the top down):[4]

    The numbers one (1) to ten (10)
    The atomic numbers of the elements hydrogen, carbon, nitrogen, oxygen, and phosphorus, which make up deoxyribonucleic acid (DNA)
    The formulas for the sugars and bases in the nucleotides of DNA
    The number of nucleotides in DNA, and a graphic of the double helix structure of DNA
    A graphic figure of a human, the dimension (physical height) of an average man, and the human population of Earth
    A graphic of the Solar System indicating which of the planets the message is coming from
    A graphic of the Arecibo radio telescope and the dimension (the physical diameter) of the transmitting antenna dish

    3
    This is the message with color added to highlight its separate parts. The actual binary transmission carried no color information.

    Space.com caught up with Drake to discuss the current state of SETI during an exclusive interview at the NASA Innovative Advanced Concepts (NIAC) 2015 symposium, which was held here from Jan. 27 to Jan. 29.

    Drake serves on the NASA NIAC External Council and is chairman emeritus of the SETI Institute in Mountain View, Calif. and director of the Carl Sagan Center for the Study of Life in the Universe.

    Space.com: What’s your view today concerning the status of SETI?

    Frank Drake: The situation with SETI is not good. The enterprise is falling apart for lack of funding. While NASA talks about “Are we alone?” as a number one question, they are putting zero money into searching for intelligent life. There’s a big disconnect there.

    We’re on the precipice. The other thing is that there are actually negative events on the horizon that are being considered.

    Space.com: And those are?

    Drake: There are two instruments, really the powerful ones for answering the “are we alone” question … the Arecibo telescope[above] and the Green Bank Telescope [GBT].

    NRAO GBT
    GBT

    They are the world’s two largest radio telescopes, and both of them are in jeopardy. There are movements afoot to close them down … dismantle them. They are both under the National Science Foundation and they are desperate to cut down the amount of money they are putting into them. And their choice is to just shut them down or to find some arrangement where somebody else steps in and provides funding.

    So this is the worst moment for SETI. And if they really pull the rug out from under the Green Bank Telescope and Arecibo … it’s suicide.

    Space.com: What happens if they close those down?

    Drake: We’re all then sitting in our living rooms and watching science fiction movies.

    Space.com: How about the international scene?

    Drake: The international scene has gone down too because all the relevant countries are cash-strapped also.

    There is a major effort in China, a 500-meter [1,640 feet] aperture spherical radio telescope. The entire reflector is under computer control with actuators. They change the shape of the reflector depending on what direction they are trying to look. The technology is very complicated and challenging. The Russians tried it and it never worked right. But … there are serious resources there.

    Space.com: Why isn’t SETI lively and bouncing along fine given all the detections?

    Drake: You would think. All those planetary detections are the greatest motivator to do SETI that we ever had. But it hasn’t had any impact, at least yet.

    Space.com: How do you reconcile the fact that exoplanet discoveries are on the upswing, yet mum’s the word from ET?

    Drake: People say that all the time … saying that you’ve been searching for years and now you’ve searched thousands of stars and found nothing. Why don’t you just give up … isn’t that the sensible thing?

    There’s a good answer to all that. Use the well-know equation and put in the parameters as we know them. A reasonable lifetime of civilizations is like 10,000 years, which is actually much more than we can justify with our own experience. It works out one in every 10 million stars will have a detectable signal. That’s the actual number. That means, to have a good chance to succeed, you have to look at a million stars at least — and not for 10 minutes — for at least days because the signal may vary in intensity. We haven’t come close to doing that. We just haven’t searched enough.

    Space.com: What are we learning about habitable zones?

    Drake: Actually the case is very much stronger for a huge abundance of life. The story seems to be that almost every star has a planetary system … and also the definition of “habitable zone” has expanded. In our system, it used to be that only Mars and Earth were potentially habitable. Now we’ve got an ocean on Europa … Titan.

    The habitable zone goes out. A habitable zone is not governed just by how far you are from the star, but what your atmosphere is. If you’ve got a lot of atmosphere, you’ve got a greenhouse effect. And that means the planet can be much farther out and be habitable.

    6
    “Radio waving” to extraterrestrials. Outward bound broadcasting from Earth has announced humanity’s technological status to other starfolk, if they are out there listening.
    Credit: Abstruse Goose

    Space.com: What is your view on the debate regarding active SETI — purposely broadcasting signals to extraterrestrials?

    Drake: There is controversy. I’m very against sending, by the way. I think it’s crazy because we’re sending all the time. We have a huge leak rate. It has been going on for years. There is benefit in eavesdropping, and you would have learned everything you can learn through successful SETI searches. There’s all kinds of reasons why sending makes no sense.

    7
    Frank Drake, center, with his colleagues, Optical SETI (OSETI) Principal Investigator Shelley Wright and Rem Stone with the 40-inch Nickel telescope at Lick Observatory in California. Outfitted with the OSETI instrument, the silver rectangular instrument package protrudes from the bottom of the telescope, plus computers, etc.
    Credit: Laurie Hatch Photography

    That reminds me of something else. We have learned, in fact, that gravitational lensing works. If they [aliens] use their star as a gravitational lens, they get this free, gigantic, super-Arecibo free of charge. They are not only picking up our radio signals, but they have been seeing the bonfires of the ancient Egyptians. They can probably tell us more about ourselves than we know … they’ve been watching all these years.

    Space.com: Can you discuss the new optical SETI efforts that you are involved with? You want to search for very brief bursts of optical light possibly sent our way by an extraterrestrial civilization to indicate their presence to us.

    Drake: It’s alive and well. We’ve gotten a couple of people who are actually giving major gifts. There’s no funding problem. There is a new instrument that has been built, and it’s going to be installed at the Lick Observatory [in California] in early March.

    The whole thing is designed to look for laser flashes. The assumption is — and this is where it gets to be tenuous — the extraterrestrials are doing us a favor. It does depend on extraterrestrials helping you by targeting you. These stellar beams are so narrow that you’ve got to know the geometry of the solar system that you’re pointing it at. They want to communicate. They have to be intent on an intentional signal specifically aimed at us. That’s a big order. So there are required actions on the part of the extraterrestrials for this to work. The big plus is that it’s cheap and relatively easy to do.

    See the full article here.

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