JPL: Earth-Size Planet Candidates Found in Habitable Zone

Find out the latest thinking about our universe.
User avatar
bystander
Apathetic Retiree
Posts: 19063
Joined: Mon Aug 28, 2006 2:06 pm
Location: Oklahoma

JPL: Earth-Size Planet Candidates Found in Habitable Zone

Post by bystander » Thu Feb 03, 2011 12:00 am

Earth-Size Planet Candidates Found in Habitable Zone
NASA JPL-Caltech Kepler | 2011 Feb 02
NASA's Kepler mission has discovered its first Earth-size planet candidates and its first candidates in the habitable zone, a region where liquid water could exist on a planet's surface. Five of the potential planets are near Earth-size and orbit in the habitable zone of smaller, cooler stars than our sun.

Candidates require follow-up observations to verify they are actual planets. Kepler also found six confirmed planets orbiting a sun-like star, Kepler-11. This is the largest group of transiting planets orbiting a single star yet discovered outside our solar system.

"In one generation we have gone from extraterrestrial planets being a mainstay of science fiction, to the present, where Kepler has helped turn science fiction into today's reality," said NASA Administrator Charles Bolden. "These discoveries underscore the importance of NASA's science missions, which consistently increase understanding of our place in the cosmos."

The discoveries are part of several hundred new planet candidates identified in new Kepler mission science data, released on Tuesday, Feb. 1. The findings increase the number of planet candidates identified by Kepler to-date to 1,235. Of these, 68 are approximately Earth-size; 288 are super-Earth-size; 662 are Neptune-size; 165 are the size of Jupiter and 19 are larger than Jupiter. Of the 54 new planet candidates found in the habitable zone, five are near Earth-sized. The remaining 49 habitable zone candidates range from super-Earth size -- up to twice the size of Earth -- to larger than Jupiter.

The findings are based on the results of observations conducted May 12 to Sept. 17, 2009, of more than 156,000 stars in Kepler's field of view, which covers approximately one four-hundredth of the sky.

"The fact that we've found so many planet candidates in such a tiny fraction of the sky suggests there are countless planets orbiting sun-like stars in our galaxy," said William Borucki of NASA's Ames Research Center in Moffett Field, Calif., the mission's science principal investigator. "We went from zero to 68 Earth-sized planet candidates and zero to 54 candidates in the habitable zone, some of which could have moons with liquid water."

Among the stars with planetary candidates, 170 show evidence of multiple planetary candidates. Kepler-11, located approximately 2,000 light years from Earth, is the most tightly packed planetary system yet discovered. All six of its confirmed planets have orbits smaller than Venus, and five of the six have orbits smaller than Mercury's. The only other star with more than one confirmed transiting planet is Kepler-9, which has three. The Kepler-11 findings will be published in the Feb. 3 issue of the journal Nature.

"Kepler-11 is a remarkable system whose architecture and dynamics provide clues about its formation," said Jack Lissauer, a planetary scientist and Kepler science team member at Ames. "These six planets are mixtures of rock and gases, possibly including water. The rocky material accounts for most of the planets' mass, while the gas takes up most of their volume. By measuring the sizes and masses of the five inner planets, we determined they are among the lowest-mass confirmed planets beyond our solar system."

All of the planets orbiting Kepler-11 are larger than Earth, with the largest ones being comparable in size to Uranus and Neptune. The innermost planet, Kepler-11b, is 10 times closer to its star than Earth is to the sun. Moving outward, the other planets are Kepler-11c, Kepler-11d, Kepler-11e, Kepler-11f, and the outermost planet, Kepler-11g, which is half as far from its star as Earth is from the sun.

The planets Kepler-11d, Kepler-11e and Kepler-11f have a significant amount of light gas, which indicates that they formed within a few million years of the system's formation.

"The historic milestones Kepler makes with each new discovery will determine the course of every exoplanet mission to follow," said Douglas Hudgins, Kepler program scientist at NASA Headquarters in Washington.

Kepler, a space telescope, looks for planet signatures by measuring tiny decreases in the brightness of stars caused by planets crossing in front of them. This is known as a transit. Since transits of planets in the habitable zone of sun-like stars occur about once a year and require three transits for verification, it is expected to take three years to locate and verify Earth-size planets orbiting sun-like stars.

The Kepler science team uses ground-based telescopes and NASA's Spitzer Space Telescope to review observations on planetary candidates and other objects of interest the spacecraft finds. The star field that Kepler observes in the constellations Cygnus and Lyra can only be seen from ground-based observatories in spring through early fall. The data from these other observations help determine which candidates can be validated as planets.
NASA's Kepler Spacecraft Discovers Extraordinary New Planetary System
NASA Ames Research Center | Kepler | 2011 Feb 02
Scientists using NASA's Kepler, a space telescope, recently discovered six planets made of a mix of rock and gases orbiting a single sun-like star, known as Kepler-11, which is located approximately 2,000 light years from Earth.

"The Kepler-11 planetary system is amazing," said Jack Lissauer, a planetary scientist and a Kepler science team member at NASA's Ames Research Center, Moffett Field, Calif. "It’s amazingly compact, it’s amazingly flat, there’s an amazingly large number of big planets orbiting close to their star - we didn’t know such systems could even exist."

In other words, Kepler-11 has the fullest, most compact planetary system yet discovered beyond our own.

"Few stars are known to have more than one transiting planet, and Kepler-11 is the first known star to have more than three," said Lissauer. "So we know that systems like this are not common. There’s certainly far fewer than one percent of stars that have systems like Kepler-11. But whether it’s one in a thousand, one in ten thousand or one in a million, that we don’t know, because we only have observed one of them."

All of the planets orbiting Kepler-11, a yellow dwarf star, are larger than Earth, with the largest ones being comparable in size to Uranus and Neptune. The innermost planet, Kepler-11b, is ten times closer to its star than Earth is to the sun. Moving outwards, the other planets are Kepler-11c, Kepler-11d, Kepler-11e, Kepler-11f, and the outermost planet, Kepler-11g, which is twice as close to its star than Earth is to the sun.

"The five inner planets are all closer to their star than any planet is to our sun and the sixth planet is still fairly close," said Lissauer.

If placed in our solar system, Kepler-11g would orbit between Mercury and Venus, and the other five planets would orbit between Mercury and our sun. The orbits of the five inner planets in the Kepler-11 planetary system are much closer together than any of the planets in our solar system. The inner five exoplanets have orbital periods between 10 and 47 days around the dwarf star, while Kepler-11g has a period of 118 days.

"By measuring the sizes and masses of the five inner planets, we have determined they are among the smallest confirmed exoplanets, or planets beyond our solar system," said Lissauer. "These planets are mixtures of rock and gases, possibly including water. The rocky material accounts for most of the planets' mass, while the gas takes up most of their volume."

According to Lissauer, Kepler-11 is a remarkable planetary system whose architecture and dynamics provide clues about its formation. The planets Kepler-11d, Kepler-11e and Kepler-11f have a significant amount of light gas, which Lissauer says indicates that at least these three planets formed early in the history of the planetary system, within a few million years.

A planetary system is born when a molecular cloud core collapses to form a star. At this time, disks of gas and dust in which planets form, called protoplanetary disks, surround the star. Protoplanetary disks can be seen around most stars that are less than a million years old, but few stars more than five million years old have them. This leads scientists to theorize that planets which contain significant amounts of gas form relatively quickly in order to obtain gases before the disk disperses.

The Kepler spacecraft will continue to return science data about the new Kepler-11 planetary system for the remainder of its mission. The more transits Kepler sees, the better scientists can estimate the sizes and masses of planets.

"These data will enable us to calculate more precise estimates of the planet sizes and masses, and could allow us to detect more planets orbiting the Kepler-11 star," said Lissauer. "Perhaps we could find a seventh planet in the system, either because of its transits or from the gravitational tugs it exerts on the six planets that we already see. We’re going to learn a fantastic amount about the diversity of planets out there, around stars within our galaxy."

A space observatory, Kepler looks for the data signatures of planets by measuring tiny decreases in the brightness of stars when planets cross in front of, or transit, them. The size of the planet can be derived from the change in the star's brightness. The temperature can be estimated from the characteristics of the star it orbits and the planet's orbital period.

The Kepler science team is using ground-based telescopes, as well as the Spitzer Space Telescope, to perform follow-up observations on planetary candidates and other objects of interest found by the spacecraft. The star field that Kepler observes in the constellations Cygnus and Lyra can only be seen from ground-based observatories in spring through early fall. The data from these other observations help determine which of the candidates can be identified as planets.

Kepler will continue conducting science operations until at least November 2012, searching for planets as small as Earth, including those that orbit stars in the habitable zone, where liquid water could exist on the surface of the planet. Since transits of planets in the habitable zone of solar-like stars occur about once a year and require three transits for verification, it is predicted to take at least three years to locate and verify an Earth-size planet.

"Kepler can only see 1/400 of the sky," said William Borucki of NASA’s Ames Research Center, Moffett Field, Calif., and the mission’s science principal investigator. "Kepler can find only a small fraction of the planets around the stars it looks at because the orbits aren’t aligned properly. If you account for those two factors, our results indicate there must be millions of planets orbiting the stars that surround our sun."
NASA Finds Earth-size Planet Candidates in the Habitable Zone
NASA Ames Research Center | Kepler | 2011 Feb 02
Is our Milky Way galaxy home to other planets the size of Earth? Are Earth-sized planets common or rare? NASA scientists seeking answers to those questions recently revealed their discovery.

"We went from zero to 68 Earth-sized planet candidates and zero to 54 candidates in the habitable zone - a region where liquid water could exist on a planet’s surface. Some candidates could even have moons with liquid water," said William Borucki of NASA’s Ames Research Center, Moffett Field, Calif., and the Kepler Mission’s science principal investigator. "Five of the planetary candidates are both near Earth-size and orbit in the habitable zone of their parent stars."

Planet candidates require follow-up observations to verify they are actual planets.

"We have found over twelve hundred candidate planets - that’s more than all the people have found so far in history," said Borucki. "Now, these are candidates, but most of them, I’m convinced, will be confirmed as planets in the coming months and years."

The findings increase the number of planet candidates identified by Kepler to-date to 1,235. Of these, 68 are approximately Earth-size; 288 are super-Earth-size; 662 are Neptune-size; 165 are the size of Jupiter and 19 are larger than Jupiter. Of the 54 new planet candidates found in the habitable zone, five are near Earth-sized. The remaining 49 habitable zone candidates range from super-Earth size -- up to twice the size of Earth -- to larger than Jupiter. The findings are based on the results of observations conducted May 12 to Sept. 17, 2009 of more than 156,000 stars in Kepler’s field of view, which covers approximately 1/400 of the sky.

"The fact that we’ve found so many planet candidates in such a tiny fraction of the sky suggests there are countless planets orbiting stars like our sun in our galaxy," said Borucki. "Kepler can find only a small fraction of the planets around the stars it looks at because the orbits aren’t aligned properly. If you account for those two factors, our results indicate there must be millions of planets orbiting the stars that surround our sun."

“We’re about half-way through Kepler’s scheduled mission," said Roger Hunter, the Kepler project manager. "Today’s announcement is very exciting and portends many discoveries to come. It’s looking like the galaxy may be littered with many planets.”

Among the stars with planetary candidates, 170 show evidence of multiple planetary candidates, including one, Kepler-11, that scientists have been able to confirm that has no fewer than six planets.

"Another exciting discovery has been the tremendous variations in the structure of the confirmed planets – some have the density of Styrofoam and others are denser than iron. The Earth's density is in between."

"The historic milestones Kepler makes with each new discovery will determine the course of every exoplanet mission to follow," said Douglas Hudgins, Kepler program scientist at NASA Headquarters in Washington.

Kepler, a space telescope, looks for planet signatures by measuring tiny decreases in the brightness of stars caused by planets crossing in front of them - this is known as a transit.

Since transits of planets in the habitable zone of sun-like stars occur about once a year and require three transits for verification, it is expected to take three years to locate and verify Earth-size planets orbiting sun-like stars.

The Kepler science team uses ground-based telescope and the Spitzer Space Telescope to perform follow-up observations on planetary candidates and other objects of interest found with the spacecraft. The star field that Kepler observes in the constellations Cygnus and Lyra can only be seen from ground-based observatories in spring through early fall. The data from these other observations helps determine which of the candidates can be validated as planets.

"The first four months of data have given us an enormous amount of interesting information for the science community to explore and to find the planets among the candidates that we have found," said Borucki. "Keep in mind, in the future, we’ll have even more data for small planets in and near the habitable zone for everyone to look at."

Kepler will continue conducting science operations until at least November 2012, searching for planets as small as Earth, including those that orbit stars in a warm habitable zone where liquid water could exist on the surface of the planet. Since transits of planets in the habitable zone of solar-like stars occur about once a year and require three transits for verification, it is expected to take three years to locate and verify Earth-size planets orbiting sun-like stars.

Borucki predicted that the search using the Kepler spacecraft’s continuous and long-duration capability will significantly enhance scientists’ ability to determine the distributions of planet size and orbital period in the future.

"In the coming years, Kepler’s capabilities will allow us to find Earth-size planets in the habitable zone of other stars," Borucki said. "Future missions will be developed to study the composition of planetary atmospheres to determine if they are compatible with the presence of life. The design for these missions depends of Kepler finding whether Earth-size planets in the habitable zone are common or rare."

The Kepler Mission team has discovered a total of 15 exoplanets, including the smallest known exoplanet, Kepler-10b.

"Kepler is providing data 100 times better than anyone has ever done before," said Borucki. "It’s exploring a new part of phase space, a new part of the universe that could not be explored without this kind of precision, so it’s producing absolutely beautiful data. We’re seeing the variability of stars like no one has ever seen before. We’re finding planets smaller than anyone has ever seen before, because the data quality is extremely good."

"In one generation we have gone from extraterrestrial planets being a mainstay of science fiction, to the present, where Kepler has helped turn science fiction into today's reality," said NASA Administrator Charles Bolden. "These discoveries underscore the importance of NASA's science missions, which consistently increase understanding of our place in the cosmos."
A Six-Planet System
NASA Astrobiology Magazine | 2011 Feb 02
Six Small Planets Orbiting a Sun-Like Star Amaze Astronomers

A remarkable planetary system discovered by NASA’s Kepler mission has six planets around a Sun-like star, including five small planets in tightly packed orbits. Astronomers at the University of California, Santa Cruz, and their coauthors analyzed the orbital dynamics of the system, determined the sizes and masses of the planets, and figured out their likely compositions -- all based on Kepler’s measurements of the changing brightness of the host star (called Kepler-11) as the planets passed in front of it.

“Not only is this an amazing planetary system, it also validates a powerful new method to measure the masses of planets,” said Daniel Fabrycky, a Hubble postdoctoral fellow at UC Santa Cruz, who led the orbital dynamics analysis. Fabrycky and Jack Lissauer, a scientist at NASA Ames Research Center in Mountain View, are the lead authors of a paper on Kepler-11 published in the February 3 issue of Nature.

The five inner planets in the Kepler-11 system range in size from 2.3 to 13.5 times the mass of the Earth. Their orbital periods are all less than 50 days, so they orbit within a region that would fit inside the orbit of Mercury in our solar system. The sixth planet is larger and farther out, with an orbital period of 118 days and an undetermined mass.

“Of the six planets, the most massive are potentially like Neptune and Uranus, but the three lowest mass planets are unlike anything we have in our solar system,” said Jonathan Fortney, assistant professor of astronomy and astrophysics at UCSC, who led the work on understanding the structure and composition of the planets, along with UCSC graduate students Eric Lopez and Neil Miller.

The Kepler space telescope detects planets that “transit” or pass in front of their host star, causing periodic dips in the brightness of the star as measured by the telescope’s sensitive photometer. The amount of the brightness reduction tells scientists how big the planet is in terms of its radius. The time between transits tells them its orbital period. To determine the planets’ masses, Fabrycky analyzed slight variations in the orbital periods caused by gravitational interactions among the planets.

“The timing of the transits is not perfectly periodic, and that is the signature of the planets gravitationally interacting,” he said. “By developing a model of the orbital dynamics, we worked out the masses of the planets and verified that the system can be stable on long time scales of millions of years.”

Previously, detections of transiting planets have been followed up with observations from powerful ground-based telescopes to confirm the planet and determine its mass using Doppler spectroscopy, which measures the “wobble” in the motion of the star caused by the gravitational tug of the planet. With Kepler-11, however, the planets are too small and the star (2,000 light-years away) is too faint for Doppler spectroscopy to work. This is likely to be the case with many of the planets detected by the Kepler mission, the main goal of which is to find small, Earth-size planets in the habitable zones of their stars.

“We will need to use orbital dynamics a lot with the Kepler mission to measure the masses of planets, so we expect to be doing a lot of those analyses,” Fabrycky said.

More than 100 transiting planets have been observed by Kepler and other telescopes, but the vast majority of them are Jupiter-like gas giants, and almost all of them are in single-planet systems. The Kepler-11 system is remarkable in terms of the number of planets, their small sizes, and their closely packed orbits. Before this, astronomers had determined both size and mass for only three exoplanets smaller than Neptune. Now, a single planetary system has added five more. The sixth planet in Kepler-11 is separated enough from the others that the orbital perturbation method can’t be used to determine its mass, Fabrycky said.

As is the case in our solar system, all of the Kepler-11 planets orbit in more or less the same plane. This finding reinforces the idea that planets form in flattened disks of gas and dust spinning around a star, and the disk pattern is conserved after the planets have formed, Fabrycky said. “The coplanar orbits in our solar system inspired this theory in the first place, and now we have another good example. But that and the Sun-like star are the only parts of Kepler-11 that are like the solar system,” he said.

The densities of the planets (derived from mass and radius) provide clues to their compositions. All six planets have densities lower than Earth’s. “It looks like the inner two could be mostly water, with possibly a thin skin of hydrogen-helium gas on top, like mini-Neptunes,” Fortney said. “The ones farther out have densities less than water, which seems to indicate significant hydrogen-helium atmospheres.”

That’s surprising, because a small, hot planet should have a hard time holding onto a lightweight atmosphere. “These planets are pretty hot because of their close orbits, and the hotter it is the more gravity you need to keep the atmosphere,” Fortney said. “My students and I are still working on this, but our thoughts are that all these planets probably started with more massive hydrogen-helium atmospheres, and we see the remnants of those atmospheres on the ones farther out. The ones closer in have probably lost most of it.”

One reason a six-planet system is so exciting is that it allows scientists to make these kinds of comparisons among planets within the same system. “That’s really powerful, because we can work out what’s happened to this system as a whole,” Fortney said. “Comparative planetary science is how we’ve come to understand our solar system, so this is much better than just finding more solitary hot Jupiters around other stars.”

For example, the presence of small planets with hydrogen-helium atmospheres suggests that this system formed relatively quickly, he said. Studies indicate that stellar disks lose their hydrogen and helium gas within about 5 million years. “So it tells us how quickly planets can form,” Fortney said.

The inner planets are so close together that it seems unlikely they formed where they are now, he added. “At least some must have formed farther out and migrated inward. If a planet is embedded in a disk of gas, the drag on it leads to the planet spiraling inward over time. So formation and migration had to happen early on.”

The Nature paper’s 39 coauthors include scientists at 16 institutions. This research was funded by NASA.
A closely packed system of low-mass, low-density planets transiting Kepler-11 - JJ Lissauer et al Six small planets orbiting a Sun-like star amaze astronomers
University of California, Santa Cruz | 2011 Feb 02

UF astronomers, NASA team find six closely packed planets orbiting same star
University of Florida | 2011 Feb 02

NASA Finds Earth-Size Planet Candidates; UCSB, Las Cumbres Scientists Play Key Role in Mission
University of California, Santa Barbara | 2011 Feb 02
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk.
— Garrison Keillor

User avatar
bystander
Apathetic Retiree
Posts: 19063
Joined: Mon Aug 28, 2006 2:06 pm
Location: Oklahoma

Re: JPL: Earth-Size Planet Candidates Found in Habitable Zon

Post by bystander » Thu Feb 03, 2011 12:13 am

Astronomy: Beyond the stars
Nature News | Eugenie Samuel Reich | 2011 Feb 02
Launched in 2009 to seek out worlds beyond the Solar System, the Kepler mission is exceeding expectations. Is it closing in on another Earth?
Astronomy: Exoplanets on the cheap
Nature News | Lee Billings | 2011 Feb 02
The search for planets outside our Solar System will always be pricey. But creative solutions are proving that it no longer has to break the bank.
Earth 2.0
Nature Editorial | 2011 Feb 02
The hunt is on for a distant planet similar to our own. Astronomers should decide just how similar it needs to be, before the candidates start pouring in.
A Disturbingly Weird Exoplanet System
Science NOW | Richard A. Kerr | 2011 Feb 02
Today's news that the Kepler spacecraft has turned up an alien solar system with five of its six known planets bunched tightly around their star had a familiar ring. In the past 15 years, astronomers have identified hundreds of solar systems, each bizarre in its own way. Yet this new system offers a unique way to learn more about how planets form and evolve.
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk.
— Garrison Keillor

User avatar
bystander
Apathetic Retiree
Posts: 19063
Joined: Mon Aug 28, 2006 2:06 pm
Location: Oklahoma

Re: JPL: Earth-Size Planet Candidates Found in Habitable Zon

Post by bystander » Thu Feb 03, 2011 6:35 am

A Wealth of Worlds: Kepler Spacecraft Finds 6 New Exoplanets and Hints at 1,200 More
Scientific American | John Matson | 2011 Feb 02
A newfound planetary system has six worlds, five of which rank among the smallest known, and the list of unconfirmed candidates has swelled to four figures
Kepler's Outrageous System of Six Planets
Sky & Telescope | Robert Naeye | 2011 Feb 02
I have covered developments in the field of extrasolar planets since 1995, when the first planet around a Sun-like star was announced around 51 Pegasi. With the pace of discovery advancing at a seeming exponential rate (the current tally is 525 and rising fast), I feel a bit jaded whenever a new exoplanet result is announced. It takes a lot to impress me.

Consider me impressed. In what astrophysicist Jack Lissauer (NASA/Ames Research Center) calls "the most important exoplanet discovery since 51 Peg," scientists on the team for NASA’s Kepler space telescope have announced an entirely new planetary system that seems so outrageous I almost don’t want to believe it.
Six New Planets: Mini-Neptunes Found Around Sunlike Star
National Geographic Daily News | Victoria Jaggard | 2011 Feb 02
"This is the most closely packed known planetary system," expert says.
Kepler announcement today: More than a thousand exoplanets including one 6-planet system
The Planetary Society Blog | Emily Lakdawalla | 2011 Feb 02
I wasn't able to watch the Kepler press briefing today so I will give you links to some of my favorite blogs for information on today's announcement, which follows a major data release last night as well as the publication of a paper in Nature. The bare facts, from the mission press release:

"The number of planet candidates identified by Kepler to-date [is] 1,235. Of these, 68 are approximately Earth-size; 288 are super-Earth-size; 662 are Neptune-size; 165 are the size of Jupiter and 19 are larger than Jupiter. Of the 54 new planet candidates found in the habitable zone, five are near Earth-sized. The remaining 49 habitable zone candidates range from super-Earth size -- up to twice the size of Earth -- to larger than Jupiter." In addition, they note "Kepler also found six confirmed planets orbiting a sun-like star, Kepler-11. This is the largest group of transiting planets orbiting a single star yet discovered outside our solar system."
...
And don't forget that you can help with discoveries at planethunters.org!
Exoplanet Hunter Finds Bounty of Multi-Planet Solar Systems
Wired Science | Lisa Grossman | 2011 Feb 02
The planet-hunting Kepler Space Telescope released its second batch of data today, revealing more possible new planets than have been spotted to date. The cornucopia of planetary systems includes a star orbited by six worlds, two of which appear to be watery “miniature Neptunes.”

The data cover the telescope’s first four and a half months of staring wide-eyed at 156,000 stars near the constellation Cygnus, and watching for telltale winks that signal the passing of an orbiting planet.
NASA spots six planets in tight orbits around sun-like star
ars technica | John Timmer | 2011 Feb 02
Today, the team running NASA's Kepler observatory is announcing the largest collection of planets yet spotted orbiting a single star. That star, now called Kepler-11, hosts at least a half-dozen planets, most in orbits closer to their star than Mercury is to ours. The tightly packed system consists of low-density planets, suggesting that they have a substantial gas or liquid composition at distances close enough to the star that the material risks boiling off. The whole thing, from the orbits to the planets themselves, appears to be teetering on the edge of stability.
NASA: Kepler candidates include dozens of Earth-sized planets
ars technica | John Timmer | 2011 Feb 02
When NASA scheduled a press briefing to talk about Kepler results, the safe assumption was that the focus would be on the system it had spotted with six planets orbiting a single star. That system was mentioned, but the Kepler scientists took the opportunity to provide a status report on the entire mission. And the orbiting observatory has quite a haul, with over 1,200 planet candidates (the vast majority announced today), and a few dozen each that are Earth-sized or orbiting within their star's habitable zone.
Alien solar system packs its planets like sardines
New Scientist | Rachel Courtland | 2011 Feb 02
If you thrill at the discovery of new exoplanets, hold tight. A sextuplet alien solar system has been glimpsed in exquisite detail, revealing six planets of varying mass, five of which are packed closer to one another than in any planetary system seen before.
Spacecraft sees signs of 1,200-plus worlds
Science News | Ron Cowen | 2011 Feb 02
Kepler mission releases details on newly discovered candidate extrasolar planets

Astronomers have identified 1,235 candidate planets beyond the solar system, including 54 where life might have a chance of gaining a foothold.

Extrapolating from the findings, which are based on observations of bright stars in a tiny patch of sky monitored by NASA’s Kepler spacecraft, some 20,000 planets may reside in other regions of the Milky Way where liquid water is stable, says Kepler chief scientist Bill Borucki of NASA’s Ames Research Center in Mountain View, Calif. He reported the results, which are based on Kepler’s first four months of operation, at a NASA press briefing on February 2.
Kepler Discovers 6-Planet Exo-Solar System
Universe Today | Nancy Atkinson | 2011 Feb 02
Using data from the Kepler space telescope, scientists have discovered a horde of six planets orbiting a sun-like star, approximately 2,000 light years from Earth. This is the largest group of planets detected so far around another star. The planets in this newly found solar system are relatively small – they range from 2.3 to 13.5 times the mass of the Earth – and are amazing mix of rock and gases. All six planets are crowded within an orbit the size of Venus’ orbit around our Sun; however, the inner five are closer to their star than any planet in our solar system.
Kepler Discovers First Earth Sized Planets inside Habitable Zone
Universe Today | Ken Kremer | 2011 Feb 02
With the new finding of dozens of Earth-sized extrasolar, NASA’s Kepler planet hunting space telescope has just revolutionized our understanding of Earths place in the Universe and the search for Extraterrestrial Life. And the historic science discovery is based on data collected in just the first few months of operation of the powerful telescope as it scans only a tiny portion of the sky.

The discovery of 1235 new extrasolar planet candidates was announced today (Feb.2) by NASA and Kepler scientists at a media briefing. 68 of these planet candidates are Earth-sized. Another 288 are Super-Earth-size, 662 are Neptune-size and 165 are Jupiter-size. Most of these candidates orbit stars like our sun.

Even more significant is that 54 of the planet candidates are located within the ‘habitable zone’ of their host stars and 5 of those are Earth-sized. Before today we knew of exactly ZERO Earth-sized planets within the habitable zone. Now there are 5.
Motherlode of potential planets found: more than 1200 alien worlds!
Discover Blogs | Bad Astronomy | 2011 Feb 02
Big news from the Kepler mission: more than 1200 potential planets have been found by the orbiting observatory!

This is incredible! Even though I was expecting a number like this, actually hearing it for real is stunning. In 15 years we’ve found about 500 planets orbiting other stars, but in the almost two years since Kepler launched it may have easily tripled that number! Now, to be careful: these are candidate planets, which means they have not been confirmed. But in most cases these look pretty good, and if these numbers hold up it indicates that our galaxy is lousy with planets. They’re everywhere.

And it gets better: of those planets found, 54 are in their stars’ habitable zones. Now, many of these are massive planets unlikely to be Earth-like, but the huge news is that five are near-Earth sized, and one is actually very close to Earth’s size!

If this pans out, then it implies there could be a million Earth-like planets in the Milky Way galaxy.
Kepler finds a mini solar system!
Discover Blogs | Bad Astronomy | 2011 Feb 02
Using NASA’s orbiting Kepler observatory, astronomers have found a complete solar system of six planets orbiting a sun-like star… and it’s really weird: five of the six planets huddle closer to their star than Mercury does to the Sun!

None of them is what I would call precisely earth-like — they’re all more massive and much hotter than Earth — but their properties are intriguing, and promise that more wonderful discoveries from Kepler are coming.
NASA Identifies 54 Potentially Habitable Alien Planets
Space.com | Denise Chow | 2011 Feb 02
NASA unveiled a wealth of new data from its planet-seeking Kepler space telescope today (Feb. 2) - observations that significantly increase the number of possible alien planets and identify potential Earth-size worlds, including 54 planets that could be habitable.

To date, more than 500 alien planets outside of our solar system have been discovered, but that number could more than double if all the candidate exoplanets from the new Kepler data are confirmed. Amid the 1,200 possible alien worlds, Kepler has already found 68 potentially Earth-size planets.

"We went from zero to 68 Earth-sized planet candidates and zero to 54 candidates in the habitable zone - a region where liquid water could exist on a planet’s surface. Some candidates could even have moons with liquid water," said William Borucki of NASA’s Ames Research Center in Moffett Field, Calif., the Kepler mission’s science principal investigator. "Five of the planetary candidates are both near Earth-size and orbit in the habitable zone of their parent stars."

The new data also reveal that smaller worlds and multi-planet systems may be more common than previously thought. The data release is based on observations conducted between May 2 and Sept. 17, 2009.
Astronomers Find 6-Pack of Planets in Alien Solar System
Space.com | Denise Chow | 2011 Feb 02
Astronomers have discovered an alien solar system in which six planets are orbiting a sunlike star, with five of the newfound worlds in close-knit configuration.

Few stars have been observed with planetary arrangements like our solar system, making this a compelling find. The newfound exoplanet system was sighted by astronomers using NASA's planet-hunting Kepler space observatory.

The smallest of the new alien planets is about 2.3 times the mass of Earth. None of the extrasolar planets are inside the so-called "habitable zone"—– orbits where liquid water could exist on their surfaces, scientists said.
Tourist’s Guide to the New Alien Planet System Kepler-11
Space.com | Denise Chow | 2011 Feb 02
The new discovery of six alien planets orbiting a sunlike star may be only a small part of the data released today (Feb. 2) from NASA's planet-hunting Kepler mission, but it is significant as the most tightly packed planetary arrangement around a single star yet discovered.

The six planets orbiting Kepler-11 are all larger than Earth, with the largest ones comparable in size to Uranus and Neptune. As far as exoplanets go, these are relatively small worlds.

Kepler-11 is located approximately 2,000 light-years from Earth. Astronomers used observations made by the Kepler spacecraft to detect the six planets that transit — pass in front of — the star.

The innermost planet, Kepler-11b, is 10 times closer to its star than Earth is to the sun. Moving outward, the other planets are Kepler-11c, Kepler-11d, Kepler-11e, Kepler-11f and the outermost planet, Kepler-11g, which is half as far from its star as Earth is from the sun.

None of the extrasolar planets are inside the so-called "habitable zone" – orbits where water could exist as a liquid on their surfaces, scientists said.
Alien Planet Hunt's Next Big Step: Finding Another Earth
Space.com | Mike Wall | 2011 Feb 03
NASA's Kepler mission has already found more than 1,200 potential alien planets, but it will likely be a few years before it hauls in the exoplanet "holy grail" – an alien Earth.

Scientists announced yesterday (Feb. 2) that the Kepler space telescope spotted 1,235 exoplanet candidates in its first four months of operation, including 54 that orbit their host stars in the so-called "habitable zone," that just-right range of distances that allow liquid water to exist.

While these finds are intriguing, none of the new planet candidates is likely to be a close Earth analogue, researchers said – even if a planet lies in the habitable zone, it may not be the same size and composition as Earth. Since our planet is the only world known to host life, finding and confirming an Earth twin could be a huge leap forward in the search for alien life.

"No one is more eager to get to that than the Kepler team," Douglas Hudgins, a Kepler program scientist at NASA headquarters in Washington, D.C., told reporters yesterday. "However, that's going to take time."
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk.
— Garrison Keillor

User avatar
bystander
Apathetic Retiree
Posts: 19063
Joined: Mon Aug 28, 2006 2:06 pm
Location: Oklahoma

UT: Video Visualization of Kepler Exoplanet Data

Post by bystander » Thu Feb 10, 2011 6:50 pm

Video Visualization of Kepler Exoplanet Data
Universe Today | Nancy Atkinson | 2011 Feb 10
Kepler Exoplanet Candidates from blprnt

This is really nifty: a visualization of the 1,235 exoplanet candidates observed by Kepler in the recently released data, created by Jer Thorp. In the video, all the candidates are shown as if orbiting a single star – just for the purposes of comparisons. The size of the colored dot is proportional to the size of the planet, and two of the most promising candidates for habitability are highlighted (KOI 326.01 and KOI 314.02).

You can see more visualizations on Boing Boing, Jer Thorp’s Vimeo site, and Ian Musgrave on Astroblog has some other links vizualizations and other things done with the Kepler data.
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk.
— Garrison Keillor