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Astronomers Find Alien Planet With The Longest Year

July 24, 2014 by Michael  
Filed under Around The Net

A newfound alien planet is one for the record books.

The alien planet Kepler-421b — which crosses the face of, or transits, its host star from Earth’s perspective — takes 704 Earth days to complete one orbit, and thus has the longest year known for any transiting alien world, researchers said. (For comparison, Earth orbits the sun once every 365 days, and Mars completes a lap every 780 days.)

“Finding Kepler-421b was a stroke of luck,” study lead author David Kipping, of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, said in a statement. “The farther a planet is from its star, the less likely it is to transit the star from Earth’s point of view. It has to line up just right.” [10 Exoplanets That Could Host Alien Life]

To be clear, Kepler-421b does not have the longest year of any known alien planet. Many nontransiting worlds have much more far-flung orbits, including the gas giant GU Piscium b, which takes about 160,000 years to complete a lap around its host star.

Kepler-421b, which is about the size of Uranus, is located about 1,000 light-years from Earth, in the constellation Lyra. It was spotted by NASA’s Kepler space telescope, which launched in March 2009 to hunt for transiting exoplanets by noting the tiny brightness dips caused when they cross in front of their stars.

Kepler has found nearly 1,000 alien worlds to date and has flagged more than 3,000 other “candidates” that still need to be confirmed by follow-up observations or study. Mission team members expect that at least 90 percent of these candidates will eventually turn out to be bona fide planets.

The spacecraft suffered a glitch in May 2013 that ended its original mission, but NASA recently signed off on a new mission, called K2, that will keep Kepler hunting for exoplanets, in addition to other cosmic bodies and phenomena.

Most of Kepler’s finds thus far are worlds that orbit relatively close to their parent stars, since such planets transit relatively frequently. The instrument has generally required three transits to conclusively identify an exoplanet, but Kepler-421b was detected after it crossed its host star’s face just twice, researchers said.

Kepler-421b circles its parent star, which is cooler and dimmer than Earth’s sun, at an average distance of 100 million miles (160 million kilometers), researchers said. This places the exoplanet beyond its solar system’s “snow line” — the boundary between rocky and gaseous planets. (Beyond the snow line, ice grains glom together to form gas giants, such as Jupiter and Saturn.)

Gaseous planets often don’t remain beyond the snow line, however. Astronomers have discovered many “hot Jupiters” — giant worlds that have migrated inward significantly over time and now complete an orbit in just a few days (or, in some cases, a matter of hours).

In fact, Kepler-421b’s lack of movement makes it remarkable, Kipping said.

“This is the first example of a potentially nonmigrating gas giant in a transiting system that we’ve found,” he said.

Courtesy-Space

 

Is the Hunt For Alien Planets Heating Up?

July 22, 2014 by Michael  
Filed under Around The Net

It’s a time of amazing discovery in the hunt for planets in other solar systems. Over the past six months, more than 700 exoplanets have been found. It seems that each week brings the announcement of another foreign world: a rocky orb that seems much like Earth except that it’s 17 times more massive; a colossal planet that orbits its star at a whopping 2,000 times the distance between Earth and our sun; an Earth-like planet in a two-sun system.

On July 9, three astrophysicists — Zachory Berta-Thompson, Bruce Macintosh and Marie-Eve Naud — came together to discuss this explosion in exoplanet discovery in a live webcast hosted by The Kavli Foundation, part of a continuing series that gives viewers a chance to ask questions of scientists at the forefront of some of the world’s most exciting research.

“What is really fascinating at this stage of exoplanet science is that we have many methods, and all the methods can help to find given planets — planets with certain characteristics — and bring different information,” said Naud, a University of Montreal Ph.D. student who led a recent study that discovered a strange gas giant exoplanet called GU Pisces b. “When we are able to combine different methods, we are able to see so much more.”

Combining planet-hunting methods has not only enabled the recent explosion in exoplanet discovery , but has also increased what can be inferred about each planet. Scientists are now able to determine an exoplanet’s characteristics including its size, mass and density, as well as the chemical make-up of the planet and its atmosphere.

What’s especially exciting about identifying these chemicals is that they “can tell you things like the history of the planet — how it formed,” said Macintosh, a member of the Kavli Institute for Particle Astrophysics and Cosmology and the principal investigator for the Gemini Planet Imager. “We think we understand enough about the process that formed planets in our solar system to see that it left a chemical signature in the atmosphere of, say, Jupiter and we can try to look for that same chemical signature in the atmosphere of other planets.”

All three scientists agreed that, in addition to finding and characterizing planets, there’s another burning question that makes them excited to come to work each day: the hunt for planets that could support life.

“I think it’ll be really tough, but … thanks to the Kepler mission , we now know that the rate of occurrence of potentially habitable planets around small stars is … more than one out of ten,” said Berta-Thompson, the Torres Fellow for Exoplanetary Research at the MIT Kavli Institute for Astrophysics and Space Research. “And so this does really increase our chances.”

For more on the three astrophysicists’ expectations for finding life on other planets, their favorite of the 1700 planets discovered so far, and the burning questions that makes it exciting from them to come to work each morning, watch the complete discussion, recorded live during a Google Hangout.

Courtesy-Space

 

Are Bigger Telescopes Needed To Find Alien Life?

July 18, 2014 by Michael  
Filed under Around The Net

Humanity will probably have to wait a few decades to find out if life is common beyond our own solar system.

While NASA’s James Webb Space Telescope (JWST) — which is scheduled to launch in 2018 — will be capable of finding signs of life on nearby exoplanets, a broad and bona fide hunt for life beyond Earth’s neighborhood will require bigger spacecraft that aren’t even on the agency’s books yet, experts say.

“To find evidence of actual life is going to take another generation of telescopes,” JWST telescope scientist Matt Mountain, director of the Space Telescope Science Institute in Baltimore, said during a NASA briefing Monday (July 14). “And to do that, we’re going to need new rockets, new approaches to getting into space, new approaches to large telescopes — highly advanced optical systems.”

A chance to find signs of life

The $8.8 billion JWST features 18 hexagonal mirror segments that will work together to form one 21-foot-wide (6.5 meters) mirror — larger than any other mirror that’s ever flown in space, NASA officials said. (For comparison, the agency’s iconic Hubble Space Telescope sports an 8-foot, or 2.4 m, primary mirror.)

JWST is optimized to view in infrared light. The telescope should be able to do lots of different things during its operational life, researchers say, including scanning the atmospheres of alien planets for oxygen and other gases that could be produced by living organisms. (Such delicate work is best performed by space telescopes, which don’t have to look through Earth’s atmosphere.)

JWST will work in concert with another NASA space mission in this regard, performing follow-up observations on promising nearby worlds found by the agency’s Transiting Exoplanet Survey Satellite (TESS), which is scheduled to blast off in 2017.

“With the James Webb, we have our first chance — our first capability of finding signs of life on another planet,” MIT astrophysicist Sara Seager said during Monday’s NASA briefing. “Now nature just has to provide for us.” [5 Bold Claims of Alien Life]

A numbers game

But nature may not be so willing, at least during the JWST mission, Seager and other experts stress. And it all comes down to numbers.

There is no shortage of planets in the Milky Way. Our galaxy teems with at least 100 billion planets, 10 to 20 percent of which, Mountain said, likely circle in their host star’s “habitable zone” — that just-right range of distances that could allow liquid water to exist on a world’s surface. If there’s nothing terribly special about Earth, then life should be common throughout the cosmos, many scientists think.

But most exoplanets are very far away, and all of them are faint. JWST, while large by current standards, won’t have enough light-collecting area to investigate more than a handful of potentially habitable planets, researchers say.

A spacecraft with a 33-foot (10 m) mirror would give researchers a much better chance of finding biosignatures in alien atmospheres, but Mountain would like something even bigger.

“With a 20-meter telescope, we can see hundreds of Earth-like planets around other stars,” he said. “That’s what it takes to find life.”

Laying the foundation

There are no concrete plans to build and launch such a large space telescope, whose size would pose a number of logistical and engineering challenges. However, JWST is a potentially big step along the way to this goal.

For example, the JWST team figured out how to make mirror segments with incredible precision — a skill that could come in handy down the road.

“They’re basically perfect,” said JWST senior project scientist John Mather of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who won a Nobel Prize in 2006 for his work with the agency’s Cosmic Background Explorer satellite.

“If we were to expand the mirror to the size of the continental United States, the mirror would be accurate to within 3 inches,” Mather said. “This is completely amazing technology we have now mastered and are using.”

The hunt for life on distant worlds will be a multi-generational effort that goes from TESS and JWST to other, larger space telescopes, Seager said. And overcoming the various challenges involved will almost certainly require the cooperation of a number of different countries and organizations.

“Putting together the partnership that can find Earth 2.0 is a challenge worthy of a great generation,” Mountain said.

Closer to home

All of this does not necessarily mean, however, that alien life won’t be detected until humanity launches an enormous space telescope. Indeed, confirmation that Earthlings aren’t alone in the universe may come from worlds much closer to home.

For example, NASA’s next Red Planet rover, which is due to launch in 2020, will hunt for signs of past Mars life. And both NASA and the European Space Agency have plans to mount a mission to Jupiter’s ocean-harboring moon Europa, which many experts regard as the solar system’s best best to host alien life.

Europe’s JUpiter ICy moons Explorer (JUICE) mission is currently scheduled to blast off in 2022 to study the Jovian satellites Callisto and Ganymede in addition to Europa. NASA officials have said they hope to launch a Europa mission sometime in the mid-2020s.

Courtesy-Space

Voyager 1 Goes Intersellar

July 11, 2014 by Michael  
Filed under Around The Net

New data collected by NASA’s Voyager 1 spacecraft have helped scientists confirm that the far-flung probe is indeed cruising through interstellar space, the researchers say.

Voyager 1 made headlines around the world last year when mission scientists announced that the probe had apparently left the heliosphere — the huge bubble of charged particles and magnetic fields surrounding the sun — in August 2012.

They came to this conclusion after analyzing measurements Voyager 1 made in the wake of a powerful solar eruption known as a coronal mass ejection, or CME. The shock wave from this CME caused the particles around Voyager 1 to vibrate substantially, allowing mission scientists to calculate the density of the probe’s surroundings (because denser plasma oscillates faster.) [Photo Timeline: Voyager 1's Trek to Interstellar Space]

This density was much higher than that observed in the outer layers of the heliosphere, allowing team members to conclude that Voyager 1 had entered a new cosmic realm. (Interstellar space is emptier than areas near Earth, but the solar system thins out dramatically near the heliosphere’s edge.)

The CME in question erupted in March 2012, and its shock wave reached Voyager 1 in April 2013. After these data came in, the team dug up another, much smaller CME-shock event from late 2012 that had initially gone unnoticed. By combining these separate measurements with knowledge of Voyager 1′s cruising speed, the researchers were able to trace the probe’s entry into interstellar space to August 2012.

And now mission scientists have confirmation, in the form of data from a third CME shock, which Voyager 1 observed in March of this year, NASA officials announced Monday (July 7).

“We’re excited to analyze these new data,” Don Gurnett of the University of Iowa, the principal investigator of Voyager 1′s plasma wave instrument, said in a statement. “So far, we can say that it confirms we are in interstellar space.”

Interstellar space begins where the heliosphere ends. But by some measures, Voyager 1 remains inside the solar system, which is surrounded by a shell of comets known as the Oort Cloud.

While it’s unclear exactly how far away from Earth the Oort Cloud lies, Voyager 1 won’t get there for quite a while. NASA scientists have estimated that Voyager 1 will emerge from the Oort Cloud in 14,000 to 28,000 years.

The craft launched in September 1977, about two weeks after its twin, Voyager 2. The probes embarked upon a “grand tour” of the outer solar system, giving the world some its first good looks at Jupiter, Saturn, Uranus, Neptune and the moons of these planets.

Like Voyager 1, Voyager 2 is still active and operational. It took a different route through the solar system and is expected to follow its twin into interstellar space a few years from now.

Courtesy-Space

NASA’s Kepler Begins New Mission

June 10, 2014 by Michael  
Filed under Around The Net

NASA’s hobbled Kepler spacecraft is once again seeking out strange new worlds under a new 80-day mission to hunt for alien planets.

NASA officials recently approved the new Kepler spacecraft mission (called K2) after the exoplanet-hunting space probe suffered a major malfunction last year. Two of Kepler’s reaction wheels, which are used to keep the spacecraft precisely pointed in its orbit, failed, effectively ending the telescope’s mission. Now, scientists are still using the spacecraft to search for distant worlds, albeit in a different way.

“After the loss of the second reaction wheel, there were many doubters that we would ever do anything to repurpose the spacecraft,” Kepler scientist Steve Howell said during a session here at the 224th meeting of the American Astronomical Society on Tuesday (June 3). “So I’d just like to recognize people that weren’t doubters, which were many of us, that we could find something very neat to do.”

The original $600-million Kepler space telescope launched in 2009. The spacecraft’s initial four-year mission aimed to help uncover how common Earth-like planets are in the Milky Way by staring deeply into a single patch of sky. Kepler finds worlds by spotting tiny dips in the light of a star as a planet transits across the star’s face. So far, the exoplanet-hunting craft has cataloged more than 3,800 potential alien worlds, and follow-up work has confirmed about 960 of them as true planets.

Scientists think that K2 can help add to those numbers. Because K2 missions will last about 80 days, a relatively short amount of time, some scientists want to hunt for alien planets orbiting a certain class of stars that are smaller and dimmer than the sun. The new mission could target planets around these dim stars (known as M dwarfs) because the orbital period of the planet is shorter, making it easier to see in the span of 80 days.

“If you want to find nearby planets, well, you should look at nearby stars, and 70 percent of the stars locally are M dwarfs, so you’re going to look at an M dwarf,” Ben Montet, an astrophysics graduate student at the California Institute of Technology, said during the meeting. “One other benefit is that M dwarfs are everywhere.”

Kepler is now aiming itself at several pre-planned fields of sky in the plane of Earth’s orbit, called the ecliptic, for the K2 mission. The spacecraft wasn’t designed to stay in its new orbit, so engineers have been working to be sure that the probe can perform science stably. In the new orbit, solar radiation pressure helps to balance the robotic craft, but engineers still need to correct the orbit every now and then.

The new positioning also creates some interesting challenges. Astronomers using the new K2 data have to be careful of solar system objects like asteroids and planets that could sneak into the frame.

K2 just passed an engineering test showing that the newly repurposed spacecraft can still hunt for exoplanets while staying in its orbit effectively. The new mission should now be embarking on its first full, approximately 80-day science run.

Courtesy-Space

NASA’s Voyager Probes Still Ticking Away

June 3, 2014 by Michael  
Filed under Around The Net

NASA’s Voyager 1 and Voyager 2 spacecraft are still going strong after nearly 37 years in space.

“Both spacecraft are still operating, still very healthy. I guess as healthy as we are at the table right now,” Suzanne Dodd, the Voyager project manager at NASA’s Jet Propulsion Laboratory (JPL) said, drawing a big laugh from the audience at the SpaceFest VI conference in Pasadena, California, on May 11.

Dodd was fresh out of college in 1985 when JPL recruited her as it geared up for Voyager 2′s upcoming encounter with Uranus. Nearly 30 years later, she is project manager of the Voyager Interstellar Mission under which the two spacecraft continue to explore the vast expanse of space beyond the planets.

Voyagers of the solar system

Dodd was actually the youngster on the Voyager reunion panel. She was joined by Voyager Project Scientist Ed Stone and retired Voyager Mission Design Manager Charley Kohlhase, who were both on the project when it was in the planning stages in the early 1970s.

When the Voyagers were launched in 1977, NASA expected them to last four or five years, long enough to get them through close encounters with Jupiter and Saturn. But, they just kept going and going.

Voyager 2 went on to flybys of Uranus in 1986 and Neptune in 1989. It is now about 105 astronomical units from Earth. (One AU is the average distance between the Earth and sun, about 92 million miles.) Voyager 1, which flew out of the plane of the solar system after its 1980 flyby of Saturn, is in interstellar space at 127 AUs.

Stone and Kohlhase recalled their astonishment when an image showing two exploding volcanoes on Jupiter’s moon Io came into JPL late on a Friday afternoon in March 1979. The plumes went hundreds of miles above the surface, and the fallout covered an area the size of France.

“We had what I call a terracentric view, which was based on understanding Earth,” Stone said. “Before Voyager, the only known active volcanoes in the solar system were on Earth. Then we flew by Io, a little moon about the size of our moon, with 10 times the volcanic activity of Earth. And suddenly our terracentric extrapolation just was falling way short, and that was happening time after time after time.

“It was an incredible time where every day there were so many things we were discovering that we just moved on to the next one,” Stone added. “If we didn’t understand what we were seeing right away, we said, all right, let’s wait ’til tomorrow to see what else we get.”

A groundbreaking mission

The Voyager missions also forever changed the way spacecraft were built and operated.

“The key thing about Voyager that was a revolution was it was a totally computer-controlled spacecraft that flies itself and has fault protection on board so that if something goes wrong, it takes action,” he said. “Because now it takes us 17 and a half hours to get a command up there, and it’s 17 and a half hours before we know if anything has happened.” Before the spacecraft were launched, Kohlhase had the job of sorting through some 10,000 trajectories for projected launch windows in 1976 through 1978. He used computers to determine which ones would allow the spacecraft to make the best approaches to Jupiter, Saturn and their moons. Kohlhase and the scientists settled on 110 trajectories and ultimately used two of them.

Dodd says the Voyager mission continues to throw up challenges today. The spacecraft have 20-watt transmitters – the equivalent of a refrigerator light bulb – and signals are only 1 billionth of a billionth of a watt in strength by the time they reach Earth. JPL uses the powerful antennas of the Deep Space Network to communicate with the distant spacecraft.

“The engineering challenges are extremely unique to Voyager,” Dodd said. “You’re operating instruments below temperatures that we can’t even measure. Challenges of finding out if we turn on a component that’s next to a hydrazine line, would that hydrazine line freeze or not. We don’t know.

“Another unique challenge to it is that the engineers who built this are retired, some have passed away, you need to get people like Charley out of retirement to come and talk to us,” Dodd added. “It’s a challenge engineering-wise, it’s a challenge from a knowledge standpoint of what people know. And that’s what makes this project fun.”

The Voyagers still have a lot of life left in them even after nearly four decades on space.

“Looking forward, we expect to get 10 more years of scientific data out of the Voyager spacecraft,” Dodd said. “We basically turned off everything we can turn off to save power. Backup heaters are off, backup systems are off. We’re having some serious discussions about how to move forward, because we’re almost down to the scientific instruments now.”

After that, the spacecraft could continue on for another five to seven years sending engineering signals to Earth. Engineers are already in discussions with the Deep Space Network about what experiments could be conducted with those signals before the spacecraft fall silent.

 

 

Do Astronomers Need Luck To Find Alien Life?

June 2, 2014 by Michael  
Filed under Around The Net

Humanity will have the tools to detect alien life in the next two decades, but whether scientists can actually find life in another solar system depends a lot on luck, a panel of experts said Wednesday (May 21).

While the James Webb Space Telescope, expected to launch in 2018, will have the ability to search for the chemical signatures of life in the atmospheres of alien worlds, it doesn’t necessarily guarantee that scientists will find extraterrestrial life somewhere in the universe. No one is sure how life begins or how ubiquitous it is, making it very difficult to pinpoint when and where to find it, scientists said during a session here at the National Space Symposium.

“We don’t know how many planets we’re going to have to examine before we find life, and not finding it on 10 or 100 doesn’t mean it’s not there,” John Grunsfeld, NASA’s associate administrator for the science mission directorate said during the panel. “This may be very tricky.”

Scientists can stack the odds in their favor, however. Building new, bigger space telescopes could help researchers look at more stars, making the odds better that exoplanet hunters will find signs of life — like plant-produced oxygen or potentially methane — within an atmosphere.

“We can’t really tell what life is,” MIT astrophysicist and exoplanet hunter Sara Seager said. “All we can do is work with what life does. Life metabolizes and generates gasses, so that’s what we’re looking for … The good news is, whatever life is, as long as it uses chemistry, we’re all set.”

A mission still in the early stages of development could also help scientists investigate alien worlds even without the use of a large telescope. Called a “starshade,” the huge sunflower-shaped craft would block light from a star to allow a well-positioned space telescope to look at the atmospheres of rocky planets orbiting sun-like stars, a historically difficult feat.

By using the starshade, scientists can hunt for an “Earth twin” orbiting a yellow star in the habitable zone like Earth, the only planet scientists know hosts life.

“We’ll have the capability to find it [life] and we’ll have that capability within a decade with James Webb and hopefully within two decades with an Earth twin, but beyond that, it’s really just up to chance,” Seager, who is affiliated with the starshade group, said.

Life could also be lurking in our solar system, and scientists wouldn’t necessarily need a huge telescope to figure that out. NASA has started investigating a possible mission to Jupiter’s icy moon Europa to be launched sometime in the 2020s. Scientists think it’s possible that microbial life could survive in the ocean beneath the moon’s ice shell.

Finding life under Europa’s icy shell could also impact the hunt for living things outside of the solar system.

“I think it’s fair to say that we just want to see one example,” Seager said. “If we see one, we almost know that it’s everywhere because we need to be reassured, we need confidence that life is actually ubiquitous.”

Courtesy-Space

NASA’s Kepler Gets New Marching Orders

May 22, 2014 by Michael  
Filed under Around The Net

NASA’s prolific Kepler spacecraft is back in action, a year after being sidelined by an equipment failure.

The space agency has approved a new mission called K2 for Kepler. The telescope’s original exoplanet hunt was derailed in May 2013 when the second of the spacecraft’s four orientation-maintaining reaction wheels failed, robbing it of its precision pointing ability.

“The approval provides two years of funding for the K2 mission to continue exoplanet discovery, and introduces new scientific observation opportunities to observe notable star clusters, young and old stars, active galaxies, and supernovae,” Kepler Project Manager Charlie Sobeck, of NASA’s Ames Research Center in Mountain View, California, wrote in an update today (May 16).

During the K2 mission, Kepler will stare at target fields in the plane of Earth’s orbit, known as the ecliptic, during observing campaigns that last about 75 days each. In this orientation, solar radiation pressure can help balance the spacecraft, making the most of Kepler’s compromised pointing ability, team members said.

“The team is currently finishing up an end-to-end shakedown of this approach with a full-length campaign (Campaign 0), and is preparing for Campaign 1, the first K2 science observation run, scheduled to begin May 30,” Sobeck wrote.

The $600 million Kepler mission launched in March 2009, on a four-year mission to determine how commonly Earth-like planets occur throughout the Milky Way galaxy. Kepler finds alien worlds by noting the tiny brightness dips caused when the planets cross in front of their parent stars from the instrument’s perspective.

The mission has been incredibly successful, detecting more than 3,800 potential exoplanets to date. Follow-up observations and analysis have confirmed about 960 of these, meaning that Kepler has found more than half of all known alien planets. And mission scientists expect more than 90 percent of the mission’s candidate planets will turn out to be the real deal.

NASA issued a call for new Kepler mission proposals last August, about three months after the spacecraft lost its second reaction wheel. The K2 proposal advanced to a NASA vetting stage called “senior review” in December.

The agency conducts senior reviews every two years; the last one that evaluated astrophysics missions took place in April 2012. The 2014 senior review looked at the Hubble, Chandra, Fermi, NuSTAR, Spitzer, Suzaku, Swift, XMM-Newton and WISE space missions, in addition to Kepler, NASA officials have said.

It currently costs about $18 million annually to operate Kepler and analyze its data.

Courtesy-Space

What Does NASA Have Planned For Kepler Next Mission?

April 23, 2014 by Michael  
Filed under Around The Net

NASA’s planet-hunting Kepler space telescope has just spotted Earth’s cousin. Its next big find may be Earth’s twin.

On Thursday (April 17), astronomers announced the discovery of Kepler-186f, the first Earth-size alien planet ever found in its host star’s “habitable zone” — that just-right range of distances that could allow liquid water, and perhaps life, to exist on a world’s surface.

While the discovery is a watershed moment, Kepler-186f still falls short of the ultimate prize in exoplanet science: a true “alien Earth.” That’s because the newfound world orbits a red dwarf, a star much smaller and dimmer than our own sun. [10 Exoplanets That Could Host Alien Life]

“One of the things we’ve been looking for is maybe an Earth twin, which is an Earth-size planet in the habitable zone of a sunlike star,” said Kepler scientist Tom Barclay, a member of the team that found Kepler-186f.

Kepler-186f is an “Earth-size planet in the habitable zone of a cooler star,” Barclay told Space.com. “So, while it’s not an Earth twin, it is perhaps an Earth cousin. It has similar characteristics, but a different parent.”

But that first alien Earth may lurk somewhere in Kepler’s huge data set, just waiting to be pulled out by mission scientists.

The $600 million Kepler mission launched in March 2009 to determine how common Earth-like planets are in the Milky Way galaxy. The observatory was designed to detect alien worlds using the “transit method,” in which scientists note the telltale brightness dips that result when a planet crosses, or transits, its star’s face from Kepler’s perspective.

Kepler has been incredibly successful, discovering 966 alien worlds to date — more than half of the known exoplanet tally, which hovers around 1,800 at the moment. (The exact number depends on which of the five main exoplanet catalogs is consulted.) The spacecraft has also detected nearly 3,000 additional planet candidates, the vast majority of which should be confirmed by follow-up observations or analysis, researchers say.

Kepler’s original planet hunt ended last May, when a glitch robbed the telescope of its superprecise pointing ability. But as the Kepler-186f announcement attests, the finds keep rolling in from the mission — and likely will do so for quite some time.

And the best may be yet to come from the prolific planet hunter.

“There’s still a year of data that we have to fully analyze,” Kepler principal investigator Bill Borucki, of NASA’s Ames Research Center in Moffett Field, Calif., told Space.com last month. “The data in there is of the smallest planets with the fewest transits that are the most valuable discoveries.”

Kepler has already shown that small, rocky planets like Earth are common throughout the galaxy — something astronomers didn’t know before the observatory got off the ground.

Before Kepler, planet hunters had been finding lots of “hot Jupiters” — gas giants that orbit extremely close to their host stars. These big planets likely formed farther out but then spiraled in over time, and many researchers speculated that such migrations would rid the system of any small, rocky worlds that had formed — sending them crashing into the star or ejecting them into the depths of space.

“The thought was, before the mission launched, that there might not be any [other] Earths at all. We might very well be the only Earth-like planet in the entire galaxy,” Borucki said. “Kepler has proven this completely wrong. It has proven there is an enormous number — at least a billion, several billion, probably — of Earth-size planets in the galaxy.”

And scientists may soon have some new Kepler data to start analyzing. The team has proposed a new mission for the observatory called K2, which would allow Kepler to keep hunting for exoplanets (albeit in a modified fashion) and look for other phenomena and objects as well, such as supernova explosions, asteroids and comets.

The K2 proposal is under review at NASA headquarters, and a final decision is expected in the next month or so, team members have said.

 

Courtesy-Space

NASA To Test Laser Communications System

April 21, 2014 by mphillips  
Filed under Around The Net

The SpaceX cargo spacecraft, which transport equipment needed for astronauts on the International Space Station to test optical laser communications, has big plans to test out the new concept.

The SpaceX Dragon cargo craft’s scheduled launch last week was scrubbed because of a helium leak in the Falcon 9 rocket that will carry it aloft.

Optical laser communications, also dubbed lasercom, is one of the emerging technologies that NASA is focused on trying out.

With lasercom, data is transmitted via laser beams; the technology potentially offers much higher data rates than the space agency is able to achieve with current radio frequency transmissions.

“Optical communications have the potential to be a game-changer,” said mission manager Matt Abrahamson, in a statement. “It’s like upgrading from dial-up to DSL. Our ability to generate data has greatly outpaced our ability to downlink it. Imagine trying to download a movie at home over dial-up. It’s essentially the same problem in space, whether we’re talking about low-Earth orbit or deep space.”

Abrahamson noted that many of the latest deep space missions send data back and forth at 200 to 400 kilobits per second. The new laser technology is expected to transmit data at 50 megabits per second.

Since one megabit is equal to 1,024 kilobits, that means the new communications should be up to 256 times faster.

Once the Dragon spacecraft rendezvouses with the space station, the orbiter’s robotic arm will remove it from the ship’s cargo bay and then attach it to the outside of the station. The laser test is expected to last at least three months.

A ground telescope will be used to test the new communication tool.

As the space station moves in its orbit around Earth, the ground telescope will track it and transmit a laser beacon carrying a video uplink in 100-second bursts to the orbiting instrument. The tests will help scientists better calculate the ability to point the laser, along with beam acquisition and tracking — all while the space station is traveling at approximately 17,500 miles per hour.

The new laser communications initiative is a key part of NASA’s Space Technology Mission Directorate, an arm of the space agency focused on developing technology for future space missions, as well as for life here on Earth.

 

 

Did Kepler Find Earth’s Twin?

April 21, 2014 by Michael  
Filed under Around The Net

NASA’s planet-hunting Kepler space telescope has just spotted Earth’s cousin. Its next big find may be Earth’s twin.

On Thursday (April 17), astronomers announced the discovery of Kepler-186f, the first Earth-size alien planet ever found in its host star’s “habitable zone” — that just-right range of distances that could allow liquid water, and perhaps life, to exist on a world’s surface.

While the discovery is a watershed moment, Kepler-186f still falls short of the ultimate prize in exoplanet science: a true “alien Earth.” That’s because the newfound world orbits a red dwarf, a star much smaller and dimmer than our own sun.

“One of the things we’ve been looking for is maybe an Earth twin, which is an Earth-size planet in the habitable zone of a sunlike star,” said Kepler scientist Tom Barclay, a member of the team that found Kepler-186f.

Kepler-186f is an “Earth-size planet in the habitable zone of a cooler star,” Barclay told Space.com. “So, while it’s not an Earth twin, it is perhaps an Earth cousin. It has similar characteristics, but a different parent.”

But that first alien Earth may lurk somewhere in Kepler’s huge data set, just waiting to be pulled out by mission scientists.

The $600 million Kepler mission launched in March 2009 to determine how common Earth-like planets are in the Milky Way galaxy. The observatory was designed to detect alien worlds using the “transit method,” in which scientists note the telltale brightness dips that result when a planet crosses, or transits, its star’s face from Kepler’s perspective.

Kepler has been incredibly successful, discovering 966 alien worlds to date — more than half of the known exoplanet tally, which hovers around 1,800 at the moment. (The exact number depends on which of the five main exoplanet catalogs is consulted.) The spacecraft has also detected nearly 3,000 additional planet candidates, the vast majority of which should be confirmed by follow-up observations or analysis, researchers say.

Kepler’s original planet hunt ended last May, when a glitch robbed the telescope of its superprecise pointing ability. But as the Kepler-186f announcement attests, the finds keep rolling in from the mission — and likely will do so for quite some time.

And the best may be yet to come from the prolific planet hunter.

“There’s still a year of data that we have to fully analyze,” Kepler principal investigator Bill Borucki, of NASA’s Ames Research Center in Moffett Field, Calif., told Space.com last month. “The data in there is of the smallest planets with the fewest transits that are the most valuable discoveries.”

Kepler has already shown that small, rocky planets like Earth are common throughout the galaxy — something astronomers didn’t know before the observatory got off the ground.

Before Kepler, planet hunters had been finding lots of “hot Jupiters” — gas giants that orbit extremely close to their host stars. These big planets likely formed farther out but then spiraled in over time, and many researchers speculated that such migrations would rid the system of any small, rocky worlds that had formed — sending them crashing into the star or ejecting them into the depths of space.

“The thought was, before the mission launched, that there might not be any [other] Earths at all. We might very well be the only Earth-like planet in the entire galaxy,” Borucki said. “Kepler has proven this completely wrong. It has proven there is an enormous number — at least a billion, several billion, probably — of Earth-size planets in the galaxy.”

And scientists may soon have some new Kepler data to start analyzing. The team has proposed a new mission for the observatory called K2, which would allow Kepler to keep hunting for exoplanets (albeit in a modified fashion) and look for other phenomena and objects as well, such as supernova explosions, asteroids and comets.

The K2 proposal is under review at NASA headquarters, and a final decision is expected in the next month or so, team members have said.

Courtesy-Space

 

NASA Wants Help Putting Robots On The Moon

January 22, 2014 by mphillips  
Filed under Around The Net

NASA is seeking help in creating a new robotic rover that will deliver cargo to the surface of the moon.

In an effort to advance technologies needed to get astronauts to an asteroid orMars , NASA wants to get back to the moon. The space agency needs robotic technology to help them get there.

The robotic machine NASA wants to build must be able to ferry cargo weighing 66 pounds to 1,102 pounds to various lunar sites.

The space agency is seeking proposals from the private sector and plans to create a partnership to build robotic a lunar lander..

The program is dubbed Lunar CATALYST, for Lunar Cargo Transportation and Landing by Soft Touchdown.

“As NASA pursues an ambitious plan for humans to explore an asteroid and Mars, U.S. industry will create opportunities for NASA to advance new technologies on the moon,” said Greg Williams, NASA’s deputy associate administrator for the Human Exploration and Operations Mission Directorate. “[This] will help us advance our goals to reach farther destinations.”

NASA noted that, in a partnership, the agency would be able to contribute the technical expertise of NASA staff, access to NASA center test facilities, equipment loans, and software for lander development and testing.

NASA will host a pre-proposal teleconference on Jan. 27 to giving companies a chance to ask questions about the program.

Proposals are due by March 17. The winners are expected to be announced in April.

 

Can Man Reach Mars By 2030?

January 16, 2014 by Michael  
Filed under Around The Net

Sending humans to Mars by the 2030s is affordable, a group of experts finds, but some key changes are needed if it is going to happen.

A workshop group of more than 60 individuals representing more than 30 government, industry, academic and other organizations has found that a NASA-led manned mission to Mars is feasible if the space agency’s budget is restored to pre-sequestration levels. Putting the first humans on the Red Planet would also require international cooperation and private industry support.

There is a growing consensus among the space community that a manned mission to Mars should be a priority worth working toward in the coming years, according to Chris Carberry the executive director of Explore Mars Inc., the organization that hosted the workshop with the American Astronautical Society.

“To be able to make it feasible and affordable, you need a sustainable budget,” Carberry told SPACE.com. “You need a budget that is consistent, that you can predict from year to year and that doesn’t get canceled in the next administration.”

Budget issues

While Carberry said that it is possible to launch a manned mission to Mars by the 2030s under pre-sequestration budget levels, a NASA-led human mission to Mars will probably never launch under current budgetary constraints, Carberry said.

“We’re not far off from what we need,” Carberry said. “We just need to get back into a reasonable budget, which we’re not in right now.”

President Barack Obama requested about $17.7 billion for NASA during his 2013 budget proposal, $59 million less than what the space agency received in 2012.

“[NASA] funds are divided between various missions, directorates and centers,” Carberry said via email. “Unless there was a MAJOR restructuring, it would be hard to accomplish a NASA-led Mars mission [under the current budget]. That said, major disruptive technology gains could always occur that could make it viable — we just can’t count on that happening.”

From now until the 2030s

The workshop group’s plan hinges partially upon the availability of NASA’s heavy-lifting rocket, the Space Launch System, and the space agency’s deep space crew capsule, the Orion spacecraft. SLS and Orion are both in development now, with Orion’s first unmanned test flight slated for later this year.

In December 2013, attendees affiliated with NASA, Boeing, Orbital Sciences Corp. and many others at the Affording Mars Workshop arrived at six agreements that could frame the way that space agencies work toward a manned mission to Mars. They are:

The goal of sending humans to Mars is affordable with the right partnerships (international, commercial/industrial, intergovernmental, etc.), commitment to efficiency, constancy of purpose and policy/budget consistency.

Human exploration of Mars is technologically feasible by the 2030s.

Mars should be the priority for human spaceflight over the next two to three decades.

Between now and 2030, investments and activities in the human exploration of space must be prioritized in a manner that advances the objective of initial human missions to Mars beginning in the 2030s.

Utilizing the International Space Station, including international partnerships, is essential for human missions to deep space.

Continuation of robotic precursor missions to Mars throughout the 2020s is essential for the success of human missions to Mars.

Carberry said that the experts are still not sure whether a long or short mission to the Red Planet would be best when launching the first manned mission to Mars.

Getting to Mars

As a model of international collaboration and a huge undertaking in space, the International Space Station (ISS) could provide vital lessons about getting humans to Mars, Carberry said. The space station mission, which has been newly extended through 2024, is the best example of a consistent budget set forth for a huge project in space, he added.

The only reason it [the International Space Station] has survived the years is because it’s an international mission,” Carberry said. “It is held together by international treaties and strong agreements … If we were to follow that model and maybe even move on with the partnership to the next step, that perhaps could be the greatest legacy of ISS because that’s a proven model of sustainability, because you have more holding it together than just that annual cycle.” [7 Biggest Mysteries of Mars ]

The $100 billion orbiting outpost could also be used to mimic parts of a mission to the Red Planet. Engineers could use the orbiting laboratory to demonstrate telerobotics and new spacesuits, and to work out possible problems that could arise on a trip to Mars.

Bridge mission

The workshop group also explored the idea of a mission that would bridge the space station and a manned mission to Mars. Agencies should consider such a bridge mission when moving forward toward a launch date in the 2030s, the workshop found.

The bridge mission could be anything from NASA’s ambitious plan to capture an asteroid and bring it into lunar orbit where astronauts could explore it, to a small and temporary station where astronauts can learn a little more about fending for themselves while in space.

Other missions

Private companies are planning their own trips to the Red Planet. Mars One is planning on sending a group of people to colonize the planet on a one-way mission in 2022. The company is also expected to send a lander to Mars in 2018.

The Inspiration Mars mission, now slated to launch in 2021, will launch a couple on a flyby of Mars. This private mission might be a good precursor mission before a full Martian landing, according to Carberry.

“There’s an interesting window in 2021 where they would flip by Venus, which is relatively interesting itself,” Carberry said. “If you have a crewed mission flying by Venus on the way to Mars, that’s pretty impressive.”

If the Inspiration Mars mission does launch in 2021, it may help scientists put human boots on Martian dirt by the 2030s, Carberry said

 

Do Super-Earth Planets Have Watery Climates?

January 10, 2014 by Michael  
Filed under Around The Net

The alien worlds known as “super-Earths” may be more like our own planet than previously thought, a new study suggests.

Super-Earths — exoplanets slightly larger than Earth — are common throughout the Milky Way galaxy, but because of their massive gravity, scientists have assumed they should be water worlds. According to a new model, however, tectonically active super-Earths likely store most of their water in the mantle, leaving exposed continents and oceans that could create a stable climate such as that of Earth.

“The temperate climate on Earth is not just because of liquid water, but because of exposed continents,” study researcher Nicolas Cowan of Northwestern University said here Tuesday (Jan. 7) at the 223rd meeting of the American Astronomical Society. The surface temperatures of continents act as a kind of geological thermostat, stabilizing the climate. [The Strangest Alien Planets (Gallery)]

A super-Earth with twice the radius of Earth would have 10 times the mass and 10 times the amount of water as Earth. The big planet’s gravity would be three times as large as Earth’s, squashing the planet’s topography by a factor of three and creating shallow ocean basins, researchers said.

Given so much water and a shallow place to contain it, conventional wisdom holds that a super-Earth’s oceans should overflow their basins and inundate the exoplanet.

However, on Earth, a lot of water is stored in the mantle— the rocky layer that makes up most of the planet’s volume and mass — and moves between the oceans and mantle as tectonic plates shift. Seafloor pressure, determined by gravity, controls this process.

Cowan and colleagues modeled water storage on super-Earths, finding that the heftier gravity would create massive pressure on the seafloor, forcing water into the planet’s mantle.

“We can put 80 times more water on a super-Earth and still have its surface look like Earth,” Cowan said in a statement.

As a result, these planets should have landmasses that stabilize the climate, instead of being submerged in oceans.

If these planets, which are relatively common in the galaxy, turn out to have stable climates, their ability to support life as we know would be higher than previously thought. Of course, the gravity on such worlds is much greater — perhaps three times as large — but Cowan doesn’t believe that rules out life.

“I don’t think 3-G is a big problem for habitability,” Cowan told SPACE.com, adding, “fighter pilots can handle it.”

The researchers’ model contains two major uncertainties, however. It assumes that super-Earths have plate tectonics, and it relies on estimates of the amount of water in Earth’s mantle.

The next step to confirm the model’s findings would entail launching a high-contrast imaging mission in space to take pictures of these super-Earths and verify that they actually do have continents and oceans.

“Our model is a shot from the hip, but it’s an important step in advancing how we think about super-Earths,” Cowan said.

Courtesy-Space

 

Copious Super-Earths Thought To Be In The Galaxy

December 4, 2013 by Michael  
Filed under Around The Net

Our solar system hosts a cornucopia of worlds, from the hellfire of Venus to the frozen plains of Mars to the mighty winds of Uranus. In that range, the Earth stands alone, with no planet coming close to its life-friendly position near the Sun.

Outside our solar system, however, it’s a different story. Observations using space-based and ground-based telescopes have indicated that a new class of objects dubbed super-Earths – worlds that are about two to 10 times our planet’s mass and up to two times its radius – could be among the most common type of planets orbiting other stars.

That’s because during the past few years, astronomers have found plenty of these super-sized rocky bodies orbiting different types of stars. Among these planetary systems, those around M-class stars, which are cooler and fainter than our Sun, are particularly important. Because of the low surface temperatures of these stars, the regions around them where an Earth-like planet can maintain liquid water on its surface (also known as the Habitable Zone) are closer to them — making such potentially habitable super-Earths in those regions more detectable. [6 Most Likely Places for Alien Life in the Solar System (Countdown)]

Scientists also believe that these smaller stars are the most abundant in the Sun’s corner of the universe, implying super-Earths would be plentiful in our solar neighbourhood, as well.

Nader Haghighipour is a member of the NASA Astrobiology Institute and the University of Hawaii-Manoa’s Institute for Astronomy. Among his research interests is figuring out how these worlds form, and most importantly, how they arrive in their current orbits.

Some of his work hints that migrating giant planets could be responsible for the close-in orbits of smaller bodies. Their massive gravity could excite the rocks and protoplanetary debris on their paths and cause them to be scattered out of the system or coalesce into smaller planets such as super-Earths.

“When giant planets approach the central star, especially around an M-dwarf, I’m interested in how they affect accretion of small planetesimals in a disc in front of them and how that will result in the formation of super-Earths, particularly in the habitable zone,” Haghighipour said.

Faster discovery pace for super-Earths

Haghighipour recently surveyed the state of super-Earth research in a paper that appeared in the Annual Review of Earth and Planetary Sciences. The first super-Earths were discovered in 1992 around pulsar star PSR B1257+12, but it’s only in the past five years that the pace of discovery picked up.

This was in large part due to the arrival of the NASA Kepler space telescope, which spent close to four years hunting planets in a small region of the sky in the constellation Cygnus. Kepler ended its primary mission in 2013 after the telescope exceeded its design lifetime. During this time, it provided a treasure trove of extremely high quality data that has revolutionized the field of exoplanetary science.

Short period super-Earths are easier to detect around smaller stars than those that are the Sun’s size or larger. This is because smaller stars show larger reactions to the tug of the planet as the planet orbits the star. If the planet happens to go across the face of the star from Earth’s perspective, a super-Earth blocks out more of a small star’s light, making it easier to detect.

“That super-Earths in short-period orbits around cooler and smaller stars are easier to detect   has set the ground for this becoming fashionable, and now there’s a great deal of attention in using radial velocity and transit photometry techniques to find such planets in the habitable zones of M stars,” Haghighipour said.

These planets are both detectable by the Kepler telescope and also ground-based ones. Most commonly, discoveries from the ground take place with two instruments. One of them is the High Accuracy Radial Velocity Planet Searcher (HARPS) on a European Southern Observatory 3.6m telescope at La Silla, Chile. The other is the W. M. Keck Observatory’s High Resolution Echelle Spectrograph (HiRES) in Mauna Kea, Hawaii.

While NASA scientists re-examine Kepler’s mission – its science work is on hold after two of its four reaction wheels failed – they are hard at work planning its successor mission, the Transiting Exoplanet Survey Satellite (TESS).  TESS will have both advantages and disadvantages while searching for super-Earths, Haghighipour said.

“Because TESS is going to cover the entire sky, as opposed to Kepler that focused on only one portion of the sky, it may be able to find more [exoplanets],” he said. “As far as accuracy and precision, because it’s not going to stay on one region of the sky for as long as the Kepler did, the accuracy may not be as high as that of the Kepler.”

Habitability?

One particular star system of interest to Haghighipour is Gliese 667, a triple star system which lies about 22 light-years from Earth. Haghighipour was part of a team that identified at least one super-Earth in the habitable zone of GJ 667C in 2012.

This year, another group led by the University of Göttingen in Germany revealed that where there was one super-Earth, there may actually be many.  The new analysis found that the M-star in the GJ 677 system (known as GJ 677c) has about six or seven planets, including anywhere from three to five “super-Earths” in the habitable zone. [The Strangest Alien Planets (Gallery)]

Because the star is so faint and dim, to be in its habitable zone these planets must crowd in close. The researchers estimated that the planets have very short years, between 20 and 50 days, and may even have one side perpetually facing their host star. Even in this state, however, the astronomers believe it is possible that life could survive there.

“It’s the most reliable detection [of potentially habitable exoplanets] that we’ve had,” Haghighipour said. The challenge, he added, is to understand the planets’ habitable environments from a distance.

While calculating the location of the habitable zone of a star is relatively straightforward, modelling the planets’ dynamics and climate is far trickier. It is unknown if these worlds have plate tectonics, for example – a geophysical processes that regulates the abundance of CO2 and H2O in Earth’s atmosphere. Their interiors remain masked to astronomers, and understanding exoplanet atmosphere composition is something that some teams are only starting to accomplish.

Identification efforts continue, however. Haghighipour has been working on detecting super-Earths in the habitable zones of M-stars since 2009 along with observers at the University of California, Santa Cruz and the Carnegie Institution of Washington. Gliese 667Cc is the most cited discovery from this collaboration, but there are others.

On the theoretical side, Haghighipour has two papers published in the Astrophysical Journalabout habitability in binary star systems. He also has been trying to figure out how super-Earths form at different distances from their stars.

“It’s possible each system has had its own history, and its own way of formation. There is no reason to believe that one way of formation for planets in a system, or for super-Earths in habitable zones, can be applied to all systems,” he said.

Perhaps this research could shed some light on the formation of our own solar system. Both super-Earths and “hot Jupiters” – gas giant planets that closely orbit their parent stars – appear to be common in other systems, so why not ours?

“Honestly, we have no definite answer for that. There are many different models that present  different ideas for why there are no super-Earths and hot Jupiters in our solar system. But in order for these models to be successful, they have to explain other properties of the solar system as well,” he said.

For example, a giant gas planet close to our Sun would likely have disturbed any rocky planets wanting to orbit nearby. It will be an interesting theoretical puzzle for astronomers to figure out as they continue classifying worlds outside of the solar system.

Courtesy-Space