Category Archives: Exoplanets

TRAPPIST-1

Using a collaboration of telescopes including TRAnsiting Planets and PlanetesImals Small Telescope–South,  seven new exo-planets have been found. Yesterday I eluded to all of them in the Goldilocks zone, that is not true but THREE of them are and ALL of the planets are relatively Earth-sized!

The star TRAPPIST-1 is a dwarf star,  TRAPPIST-1 is only estimated to be only eight percent (8%) of our Sun, so it’s really small.

You will notice these planets are collectively very close to their parent star and that means very fast orbital periods, ranging from just a-(Earth)day-and-a-half for the closest planet (b) to only about 20 days for the most distant planet (h).   Since the parent star is smaller and cooler that means the Goldilocks zone is much different than our own is.  Click the graphic above to be able to see the data.

 

Join The Search

If you have not participated in Zooniverse before, give it a try. I do a couple of the projects and will be doing this one too.

Backyard Worlds: Planet 9

Here is a description from Zooniverse I got in an email:
In this project you’ll be searching through images from NASA’s Wide-field Infrared Survey Explorer (WISE) mission, hunting for objects such as brown dwarfs and low-mass stars in our Solar System’s neighbourhood. You may find an object closer than Proxima Centauri (the closest star to the Sun) or even discover the Sun’s hypothesized ninth planet, which models suggest might appear in these images!

Verified 1284 New Planets

keplerupdate

Among the 1,284 newly found planets, nine of them are in the Goldilocks zone, where liquid water (and possibly life as we know it) could exist.  The count for these planets is now 21.

Here’s the press release:

NASA’s Kepler mission has verified 1,284 new planets – the single largest finding of planets to date.

“This announcement more than doubles the number of confirmed planets from Kepler,” said Ellen Stofan, chief scientist at NASA Headquarters in Washington. “This gives us hope that somewhere out there, around a star much like ours, we can eventually discover another Earth.”

Analysis was performed on the Kepler space telescope’s July 2015 planet candidate catalog, which identified 4,302 potential planets. For 1,284 of the candidates, the probability of being a planet is greater than 99 percent – the minimum required to earn the status of “planet.” An additional 1,327 candidates are more likely than not to be actual planets, but they do not meet the 99 percent threshold and will require additional study. The remaining 707 are more likely to be some other astrophysical phenomena. This analysis also validated 984 candidates previously verified by other techniques.

“Before the Kepler space telescope launched, we did not know whether exoplanets were rare or common in the galaxy. Thanks to Kepler and the research community, we now know there could be more planets than stars,” said Paul Hertz, Astrophysics Division director at NASA Headquarters. “This knowledge informs the future missions that are needed to take us ever-closer to finding out whether we are alone in the universe.”
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Mysterious Ripples Found

AU Microscopii
Source: Hubblesite.org

Hubblesite – Though astronomers have discovered thousands of planets orbiting other stars, very little is known about how they are born. The conventional wisdom is that planets coagulate inside a vast disk of gas and dust encircling newborn stars. But the details of the process are not well understood because it takes millions of years to happen as the disk undergoes numerous changes until it finally dissipates.

The young, nearby star AU Microscopii (AU Mic) is an ideal candidate to get a snapshot of planet birthing because the disk is tilted nearly edge on to our view from Earth. This very oblique perspective offers an opportunity to see structure in the disk that otherwise might go unnoticed. Astronomers are surprised to uncover fast-moving, wave-like features embedded in the disk that are unlike anything ever observed, or even predicted. Whatever they are, these ripples are moving at 22,000 miles per hour — fast enough to escape the star’s gravitational pull. This parade of blob-like features stretches farther from the star than Pluto is from our sun. They are so mysterious it’s not known if they are somehow associated with planet formation, or some unimagined, bizarre activity inside the disk.

Learn even more about AU Mic by joining the live Hubble Hangout discussion at 3:00 pm EDT on Thurs., Oct. 8 at http://hbbl.us/y6M.

SETI Talks About Kepler 452b

Here is a great video about the newly announced Kepler 452b with SETI scientists: Douglas Caldwell, Jeffrey Coughlin, Joseph Twicken. and hosted by Seth Shostak.

The Hangout fills in a lot of the blanks from the news reports.  As I expected we don’t yet have a mass or density on this planet. Once we get at least a good estimate on these numbers for 452b then we will be able to make better guesses on its composition.

We have an estimate of the diameter so that’s a start, but it’s only one bit of the equation that defines the balance the must exist. If for example, 452b has the density of Earth, we might expect an atmosphere to be much different than we have, ranging up to perhaps even Neptune-like. On the other hand the mass could be much less and the weaker gravity could allow more of the lighter gasses to be lost to space.

I am bound to guess we are very close to finding a real Earth analog. It is astounding how quickly the search is progressing.

Video

Kepler’s Hall of Fame

Eight near Earth-sized planets found by Kepler in the Goldilocks zone of their stars.  Credit: NASA
Eight near Earth-sized planets found by Kepler in the Goldilocks zone of their stars. Credit: NASA

Not so long ago there were no other planets around other stars known. Now we have over 1,500 and thoussands more candidates. The Kepler now has over 1000 confirmed planets to its credit.

So far out of all those Kepler planets, eight are less than Earth sized and are inside of the habitable zones of their parent stars. So not only are they warm enough for life like we know it, the size of the planet means the atmosphere could have similar charateristics to our own thanks to gravity. That isn’t to say they actually do, just that the potential is there. I would like to think eventually those atmospheres will be charachterized. In the mean time the search continues.

The Kepler press release:

How many stars like our sun host planets like our Earth? NASA’s Kepler Space Telescope continuously monitored more than 150,000 stars beyond our solar system, and to date has offered scientists an assortment of more than 4,000 candidate planets for further study — the 1,000th of which was recently verified.

Using Kepler data, scientists reached this millenary milestone after validating that eight more candidates spotted by the planet-hunting telescope are, in fact, planets. The Kepler team also has added another 554 candidates to the roll of potential planets, six of which are near-Earth-size and orbit in the habitable zone of stars similar to our sun.

Three of the newly-validated planets are located in their distant suns’ habitable zone, the range of distances from the host star where liquid water might exist on the surface of an orbiting planet. Of the three, two are likely made of rock, like Earth.
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Giant Rocky Planet

An artist concept shows the Kepler-10 system, home to two rocky planets. In the foreground is Kepler-10c described below.  Image Credit: Harvard-Smithsonian Center for Astrophysics/David Aguilar
An artist concept shows the Kepler-10 system, home to two rocky planets. In the foreground is Kepler-10c described below. Image Credit: Harvard-Smithsonian Center for Astrophysics/David Aguilar

A few fun facts:

Kepler-10c is 2.227 Earth radii with a similar density so it’s HUGE for a rocky planet, 17 times larger than Earth. A fact that has scientists scratching their heads on how this could be, it was thought not possible.

The parent star Kepler 10 is similar to our own Sun. Kepler-10c orbits much closer to its sun than we do ours, only 25 percent as far, this means of course the planet is hot somewhere near 212 oC / 413oF. It’s also orbits very quickly, a Kepler-10 c year is only 45.29 days.

Visit the Kepler page for all the details including how the planet was discovered.

Here is the Kepler press release:

Astronomers have discovered a rocky planet that weighs 17 times as much as Earth and is more than twice as large in size. This discovery has planet formation theorists challenged to explain how such a world could have formed.

“We were very surprised when we realized what we had found,” says astronomer Xavier Dumusque of the Harvard-Smithsonian Center for Astrophysics (CfA), who led the analysis using data originally collected by NASA’s Kepler space telescope.
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