Kepler works!

By Phil Plait | August 6, 2009 1:24 pm
Drawing of NASA’s Kepler missions

NASA held a press conference today about early scientific results from the Kepler space telescope, a mission designed to detect Earthlike planets orbiting distant stars. Kepler has not yet detected such a planet — that will take at least a couple of years to do — but the good news is that Kepler works! New results show that should they exist, Kepler has the ability to find such planets.

How do we know?

Kepler stares at a single spot in the sky, taking many many measurements of the brightnesses of about 100,000 stars all at once. If a planet is circling one of those stars, and its orbit is edge-on to us, then once every orbit the planet passes directly between us and the star. This is like an eclipse, and the light we see from the star drops a little bit. A planet like Jupiter orbiting a star like the Sun will cause a 1% drop in the light we see, because Jupiter has a radius 1/10th of the Sun’s, so the surface area of the planet is 1% of that of the star (remember, area = π x the radius squared, so 1/10 x 1/10 = 1/100 or 1%). Therefore the planet blocks 1% of the star’s surface, and we see the corresponding drop in starlight.

Earth is smaller than Jupiter, about 1/10th the radius. That means that an Earth orbiting a star blocks 1/10,000th the light of the star, or 0.01%. That’s a tiny fraction! From the ground, that’s impossible to measure due to fluctuations in Earth’s atmosphere changing the amount of light we see from the star. But from space — hey, that’s where Kepler is! — we can make far more accurate measurements.

And that’s what the news is from Kepler. As a test of its abilities, it observed the star known as HAT-P-7, which is known to have a roughly Jupiter-sized world orbiting it every 2.2 days. This planet, called HAT-P-7b, is far too close to the star to be seen directly, but every time it passes in front of the star, the light we see drops. Here’s what Kepler saw after observing this system for 10 days:

Kepler observations of HAT-P-7B

The top plot shows the data as the planet circles the star. The big dip is due to the planet blocking a fraction of the star’s light. The depth of that dip tells us how much of the star was blocked, and therefore the size of the planet. But look along the plot a little bit to the right: see that fainter dip (right under the i in "Magnification")? What’s that?

The bottom plot is the same thing but zoomed in to see more detail. That second dip is a lot more obvious. It’s not another planet blocking starlight, which is what you might first guess. It’s actually the light from the planet being blocked by the star!

The planet is reflecting light from the star, just like the Moon reflects sunlight, allowing us to see it. When the planet passes behind the star, we don’t see that light anymore, so the total light from the system drops a wee bit. It’s not much, and totally impossible to see from the ground, but Kepler was able to spot it. And that’s critical, because it turns out this dip is about the same thing we’d expect to see if a planet the size of the Earth were to pass in front of the star. In other words, the drop in light from a giant planet going behind its star is about the same as we’d expect from a smaller planet passing in front of the star.

The fact that Kepler spied this dip at all means that, if somewhere out there an Earthlike world is orbiting a star, Kepler will be able to detect it!


Another cool thing is in that data too. See how the light slowly rises and drops over time? We’re actually detecting the phases of the planet as it orbits the star! As the Moon orbits the Earth, we see it going from mostly dark (new Moon) to half lit to full, getting brighter over two weeks. Then once it’s past full we see more and more unlit surface, so it appears to dim over time. The same thing is happening to the planet HAT-P-7b as it orbits the star. Right after the eclipse event we are seeing it as "new", with the dark side facing us. As it orbits, we see more and more lit up, until it passes behind the star. After that secondary eclipse, we see the light from the planet get dimmer. The Kepler website has a great animation showing this, which I also uploaded to YouTube:

What this means is that the Kepler data are showing us the phases of an unseen planet orbiting a star more than a thousand light years away!

There is some bad news, sadly: if we want to find an actual Earthlike planet we have to be patient. It takes the Earth a year to orbit the Sun, right? So suppose we see a small dip in the light from some star that indicates a planet the size of the Earth is orbiting it. To confirm that, we’d have to wait a year to see that dip again! And even that’s not enough, since we don’t know beforehand how long the orbital period of the planet is. That second dip might be from sunspots, or another planet, or something else entirely. So we have to wait again, and spot the dip a third time. If the time interval between the two dips is the same, then we can be pretty sure we’re seeing a small planet eclipsing (actually, the correct word is transiting) its star.

In general the orbit could be days long, as it is for HAT-P-7b, or it might take months or even a year. And remember the real prize here is to find a planet like Earth, which means an orbit that takes months or more. So we really won’t have those kinds of results from Kepler for a while yet. It’s only been up and observing for a few weeks.

But come 2011 or 2012, and we may have our answer. Imagine! In just two years we may know if other Earthlike planets are orbiting stars in our galaxy!

Most astronomers, including me, assume that these planets exist, but it’ll be incredible to have the actual data. And better, Kepler is looking at so many stars that we’ll get actual statistics for these planets. We’ll be able to guess just how many such planets exist! Are we a rare specimen, or are there millions of Earths out there in the galaxy?

At this moment, this exact moment in history, the Earth is a lone habitable rock orbiting one star in the depths of space. But in just two more of our own orbits, we may suddenly find ourselves located in a planetary metropolis studded with vast numbers of worlds, all of which were just waiting to be found.

CATEGORIZED UNDER: Astronomy, Cool stuff, NASA

Comments (150)

  1. Kirk

    Science. Kicks. Ass.

  2. The stuff humans can figure out, build, and figure out more from amazes me daily. This is awesome.

  3. I’ll second that! It’s incredible that we are able to glean so much information from such tiny fluctuations in the light. Hail Science!

    Also, regarding HAT-P-7b… it’s amazing to consider a Jupiter-sized planet whipping around a star in only 2 days!

  4. Erik in SD

    That post was epic. Well done as always, Phil.

  5. Justin

    Damn it, Phil!

    You had gotten my hopes up in the context that Kepler had actually found an Earth-like planet!

    Anyway, to think, if an Earth-like planet is found, we will witness one of the biggest discoveries in the history of Science. That’s kinda cool…

  6. Yup, I saw that rise & fall in luminosity in the graph and knew that it meant planetary phases before I got to your paragraph on it. This is just -TOO- cool! I’ll try to be patient and give Kepler time to do it’s stuff.
    But it’s HARD!

  7. !AstralProjectile

    Very nice.
    However I havn’t figured out why the transit dip is so rounded at the bottom – I would have thought it would be squarer, like the other dip.

  8. csrster

    The resolution on the light curve is amazing (although I assume that the solid curve is a few-parameter model). There must be a lot of information on the stellar and planetary atmospheres in there. For example the primary dip is much smoother than the secondary dip, presumably because the star has a more extended atmosphere.

  9. MHS

    Imagine expecting to see such a trend in your data and then actually seeing it. Must be totally incredible.

    Humans rule.

  10. Gerard van Belle

    The bottom of the transit dip is rounded because of ‘limb darkening’ – the apparent brightness of the disk of a star upon the sky tends to drop as you measure it from center to edge. It’s due to the gaseous nature of the star and how radiation travels through that gas.

  11. Chris

    @!AstralProjectile: could it be due to limb darkening of the star? When the planet is just commencing or ending its transit, the amount of light it blocks is less, since the surface brightness (from Earth’s perspective) near the star’s limbs is lower.

  12. Nevy C

    Excellent news. And a wonderful post as always, Phil.

  13. Dave

    By all that is good and holy* in this world, this is far and away the most amazing thing I’ve seen in a long time! I had to physically lift my jaw off the keyboard so that I could type this comment! (Long time reader, first time writer, blah blah blah) I had edge-of-my-seat excitement reading about Kepler’s launch, and now I find I can’t wait to see what we’ll be discovering as a by-product of waiting for the Earth-like data to come in! (And I’m so excited, only copious use of the factorial sign can express my wonder!)

    The most fascinating part of the exoplanet search, for me, has always been that as soon as we have a telescope that can detect a certain type, we start finding those kinds of planets. Can only see big planets orbiting close to their stars? We find big planets orbiting close to their stars! Each time the detection limits have gotten better, we’ve been finding exactly the kinds of planets that we’re able to detect. I’m with Phil in that I assume those Earth-like worlds exist, but will still be giddy with delight when the news starts pouring in.***

    *ie, holy smokes, sh**, and every other line Burt Ward ever said to Adam West.
    ** And once the list of good and holy things in this world have been exhausted, I’ll probably have to start swearing by all the things less good and only moderately holy things before I’ve properly expressed my awe and amazement at this.
    ***Assuming the world continues to not end in 2012, of course. Oh, wait – the earth was already destroyed when the LHC came online. (I can’t believe I missed doomsday again!)

  14. StevoR

    Awesome! 8)

    Congratulations to all the folks involved with Kepler if by any chance they happen to be reading this blog! :-)

    Good to see the additional confirmation for the exoplanet HAT-P-7b too, btw.

    Come to think of it, let’s give HAT-P-7b a proper name in honor of its significance to this occasion : Kepler’s Planet maybe ..? 😉

    OTOH, Kepler does already have a Supernova remant named in his honour as well as this scope .. Oh & the Laws .. so maybe not.

    HAT-P-7b, HAT … ah Hats – name HAT-P-7b after a hat then? Somberero maybe ? No that’s already taken with the eponymous galaxy.Got it! Akubras! (Broad brimmed Aussie bushmen hats FYI .) No celestial akubras yet? Good then I officially propose HAT-P-7b now becomes the Akubra planet! 😉


    PS. Yes, I’m tired & feeling silly. How’d you guess? 😉

    PPS. Read a book last year “Heavenly intrigue”, I think it was called, that made a pretty good case that Johannes Kepler actually murdered Tycho Brahe to get his observing logs! :-0

    Not meaning to tarnish the moment for the Kepler telescope folks, hijack the thread or anything like that but just curious – has anyone else here read it too & if so what did they think?

  15. Eddy

    Is it me or does the graph in the video have an error?

    In the original measurements the lowest level of the smaller dip is about the same hight as the level just before the bigger dip. This makes sense. When the planet is behind the star you only see the light from the star. When the planet is just about to start the transition there also is only the light of the star. These level should be the same.

    In the video the lowest point of the small dip is way below the level where the big dip begins. To me this looks like a mistake.

  16. Jeremy

    I have a question. Even if we are looking at thousands of stars, what are the odds that we are seeing the planetary disc from it’s edge on? Can Kepler detect planets based on star wobble (what we would see if we are from a different angle than straight on)?

    If not, then I don’t see the awesomeness of the Kepler.

  17. Bobrocks

    OOOH This makes me all giggly inside!

  18. “The fact that Kepler spied this dip at all means that, if somewhere out there an Earthlike world is orbiting a star, Kepler will be able to detect it!”

    Earth Sized and orbit. Big difference. Will kepler tell us anything at all about water content, atmosphere, land masses or critters?

    Its awesome news anyway.

  19. T.E.L.

    sciencecomedian Said:

    “…it’s amazing to consider a Jupiter-sized planet whipping around a star in only 2 days!”

    Yes, but remember: it’s not the size of the planet, but the mass of the star (assuming the planet is trivially massive in comparison). For our sun, the radius for a circular, 2-day orbit comes to about 4.6 million kilometers from the Sun’s center.

  20. I just had a total squeee moment reading that!

    BTW, one of the companies that I am interviewing with made the primary mirror for Kepler!

  21. Eddy


    If we view edge on, you can say that the orbit is at 0 degrees.
    The opposite is 90 degrees.
    The planet can have a few degrees (somewhere between 5 and 10 degrees) tilt and we will still see a transit. So the change is between 5/90 and 10/90. So between 5 and 11% (based on even distribution of tilt)

    So, if a star has a planet, then there is about a 10% change that we see a transit … if my math is correct.

  22. John Baxter

    So much has changed since I was attempting to learn physics at MIT in the late 1950s (yikes! 50 years ago).


  23. Marc

    Given the sinusoidal phases detection, could Kepler be used to find planets that don’t actually transit? Whose orbits are tilted a little too far? Also, that wouldn’t take a full cycle to detect.

  24. Kurt Kohler

    If there were another planet transiting in front of the star would that be indicated by the dip having a round bottom? Is the “roundness” of the dip a reliable indicator of whether we’re seeing a planet transit or a star eclipse?

  25. Sili

    Somehow I’d missed the fact that Jupiter is *that* big diameterwise.

  26. Kepler stares at a single spot in the sky, taking many many measurements of the brightnesses of about 100,000 stars all at once.

    I’ve done that. Granted, I wasn’t sober at the time.

  27. StevoR

    @ 14 Dave : (I can’t believe I missed doomsday again!)

    Don’t worry you didn’t miss much.

    The apocalyse is not only over-rated, it keeps coming around way too often too! 😉

    @ 27 Naked Bunny with a Whip : Back to your old name again instead of ‘Bunny’? Good I like your old & new again tag much better! 😉

    Incidentally, I’ve heard of drunken double vision – & even experienced it myself on the odd ocassion but seeing *100,000* stars for one – WOW! You must’ve been plastered! 😀

  28. Francesco Iacopino

    That is amazing!

    Thank you for the post, I really enjoyed it. I can’t wait to get more data from Kepler!

  29. Danil

    I’m presuming that the solid line is somebody curve fitting?

    Beyond that, I seem to have Eddy’s question (“Is it me or does the graph in the video have an error?”) except that I see the same error in the still picture: the well at 2.1 looks too deep to match the minimum of the fitted sine wave. So what’s going on?

  30. rob

    so, what you’re saying is they aimed Kepler at a star to test it by finding dips. heck, they could have tested it much more easily by pointing it at earth. there are large number of dips that would give it a huge signal to detect…


    but srsly: waaaaaaay cool.

  31. Tim G
    The top of the big dip is a bit above the bottom of the small dip because the atmosphere of the planet bends some light around? Much like a lunar eclipse is red due to Earth’s atmosphere bending light?
  32. @StevoR #28: That’s a different Bunny, actually. The generic Bunny. I am the name-brand Bunny who comes with a fancy package and a toy inside.

  33. I noticed that the dips’ edges aren’t quite vertical; there’s a bit of slope to them. I’m guessing that’s the time it takes for the planet to eclipse the star (for the first dip) and the time it takes for the star to eclipse the planet (for the second). Assuming the orbital diameter is known, could this be used to verify the diameter of the planet? The rise / fall time of the second dip should be proportional to the size of the planet and, therefore, should correlate to the percentage of dimming in the first dip, right?

    Also, does the amplitude of the sine wave (minus the dips) give any additional information about the planet?

    @Danil #30: Wild guess would be that the dark side of the planet isn’t entirely dark. If the planet is emitting a small amount of light on its own (say, glowing in the infrared), that might account for the difference between the bottom of the second dip and the bottom of the sine.

  34. Killer Bee

    @ # 27 and # 33

    You must enjot caning!

  35. that’s if we are still here in 2012.

  36. Daffy


    When I was a kid they always said in science class that we would probably never know if there were planets orbiting other stars (let alone earth-type ones). I wonder what we will find out 30 years from now? Just…wow.

  37. Caleb Jones


    Does Kepler do spectrum analysis at the same time so that we also get the chemical makeup of these planets or is that left to follow up work using other instrumentation once good candidates are found?

    As far as I know you can deduce the chemical makeup of a transiting planet in a similar manner by comparing the change in spectrum analysis of the star as it is transited by the planet. Same thing the video describes but with spectrum analysis rather than light intensity.

  38. cpt Jameson Lave de Reorte

    Incredible. Is Keppler also able to analyze the light spectrums in order to detect (by deduction) elements in atmospheres, or are we going to use other telescopes for that? By what I’ve seen in your excellent article it becomes clear that we are very close to build quite accurate virtual models of distant solar systems. If we catch an earth like system and we do see fingerprints of organisms that would be a major discovery. Even if all planets we find are lifeless this is still amazing.

    Closer to home, I read some interesting articles about methane on Mars. That really is a collection of mysteries.

  39. Dave

    @StevoR: (#28)

    @ 14 Dave : (I can’t believe I missed doomsday again!)

    Don’t worry you didn’t miss much.

    The apocalyse is not only over-rated, it keeps coming around way too often too! 😉

    Seriously! There’s a limit to the number of times I can toast to the end of the world in a given week!

    On the probability of seeing other solar systems edge-on, isn’t our orbit around the sun reasonably close to being in the plane of the rotation of our galaxy? If such is common, that would certainly bolster our odds of success! Any theories on that?

  40. Jason Clary

    Pure awesomeness.

    How do you tell the difference between a small planet and a large planet that is orbiting slightly off plane from us which obscures less of the star by just grazing one edge? Will the phase give you that or would it be too noisy in a system with multiple planets?

  41. Troy

    When I first read your headline “Kepler Works”, I thought it was going to be a demonstration of Kepler’s third law. I’ve been so busy I must have missed Kepler being launched. Very good explanation of how it works, that is quite a sensitive instrument. It is a bit of a coup for the space program that it can only work from earth orbit. [Also, I believe it should be able to give some indication of the type of atmospheres of anything it finds, I recall reading that and of course if you find oxygen you either have some very bizarre chemistry or life!]

  42. don

    Eddy and Jeremy – Since our entire galaxy is disc-like, and since our own solar system’s orbits around the sun are mostly disc-like roughly in the plane of the galaxy… Isn’t it a high probability that the orbits of planets found throughout our galaxy would also be more or less around the same planes as us, closer to 0 degrees, edge on? Meaning, a low probability of rogue 90 degree orbits from our perspective, correct?

    By the way, what are the naming conventions for planets orbiting other suns?

  43. Scott R

    @Tim G(#32) & Eddy(#16)

    According to SciAm ( because the planet is extreamly close to the star, it is heated hot enough that it glows incandescently, thus the discrepancy is the glow from the planet’s night side before the transit.

  44. Steven

    Hey, could this thing spot a Dyson Swarm? Because that would be great.

  45. Okay, riddle me this –

    How can we tell the difference between an Earth-sized planet doing a full transit and a Jupiter-sized planet doing a transit that barely clips the edge of the star, so presents an attenuated dip?

  46. Martin Moran

    @ 27 Naked Bunny with a Whip : I remember a similar situation myself visiting parents in the West of Ireland the sky is sooo dark there, compared to London anyway. I dam near fell over so awesome once my eyes adjusted. Although to be fair I guess I will never know whether it was stars or the amount of Guinness I consumed that day!

  47. Paul M.

    Christopher… I’m guessing you could look at the amplitude of that sinusoidal variation. An Earth sized planet would have a much smaller range than a Jupiter sized one. Maybe the shape of the dip would be different too – the planet that makes a full transit would show that limb darkening phenomenon people have mentioned.

  48. PS, Phil – not sure how to send you news tips (if there’s an email address on your blog, I can’t seem to find it).


    Creationist museum and park to be seized and sold to satisfy tax fraud debt. Sweet 😉

  49. Steve A


    I believe that it’s because the candidate stars are all sun-like. So, if its like the sun, then planets with one year orbits should be Earth like if our understanding on how planets form based on our own solar system is correct. Now that I think of it, I’ve never seen size come into the reporting. I think that by “Earth-like” they don’t mean the size of Earth, but a rocky planet at a distance from its parent star that could have water.

  50. Roadtripper

    It’s possible there might be ‘earth-like’ worlds around stars smaller than our sun. (How much smaller? I’m not sure…there’s a good blog post topic!) In that case, their orbital period would be shorter than a year, and we could get some results from Kepler much sooner.


  51. Brian

    I had thought the Kepler methodology (transiting) was based entirely upon, er, transiting. This raises the possibility that it ain’t so, no? Reflected starlight off a planet should be almost uniformly visible. Therefore the Kepler method isn’t really transiting, but instead… predictable luminosity variations due to… planets.

    Doesn’t this make Kepler far more powerful than the design intention? I thought I heard that, due to random placement, only about 8% (or was it 4%?) of planetary systems could be expected to transit as viewed from Earth?

    Also, and this is almost too hopeful for words, but the animation raised the possibility. Could Kepler detect sunspots on the stars, as they rotate in and out of view?

    One more thing. We have to expect that some extrasolar planets will have orbital periods well beyond 1 year. Therefore some systems will take more than a year to confirm planets, right? Also, in multiple planet systems, we’ll see multiple luminosity cycles, all overlaid one on another. That could add a wrinkle to the neat and simple animation of the video clip.

  52. Travis

    Thanks for the answer Tim G. I was wondering about the dip discrepancy myself.

    So how do we find Earth like planets that aren’t transiting their parent star from our perspective? Also, how long will it be until we can start imaging some of these exoplanets?

  53. Grant H

    7. !AstralProjectile Says:
    There have been so many comments, I haven’t read them all to see if this has been answered for you yet, but the reason is the convex nature of the light source.
    The disc of light that is HAT-P-7 is not like a spot light shining all it’s light in one direction. At the edge of the disc the surface of the star is angled away from us, therefore blocking light from the edge of the disc will have less impact on the amount of light that is reaching us. As the planet moves closer to the middle of the disc, it blocks more of the light that is shining directly at us.

  54. Brian

    Phil, thanks for sharing. Updates about Kepler are always good to get — it gives us something to tide us over during the years that we have to wait for the real results.

  55. zaardvark

    Obviously I’m way off, but using the light curve I estimate the planet to be 3.5 times Jupiter’s radius. Hahaha :(. Can anyone get closer to the actual number (Wikipedia has it at 1.363 Jupiter radii.

  56. Also, how long will it be until we can start imaging some of these exoplanets?
    The SIM Lite Astrometric Observatory (formerly called the Space Interferometry Mission) may be the best bet.

  57. Mike

    Holy nuts! This is about the most interesting and exciting thing I’ve read in months.. wow! Just reading through your blog post, Phil, I was hanging on every word. Detecting the phases of a planet around a distant star! O_O

    I reiterate the first comment in this post: Science. Kicks. Ass.

  58. Joe C

    While I admire Phil’s purely scientific and even-handed view that Kepler will discover IF there are other Earth-like planets, I feel safe in saying and I best to be honest that secretly Phil agrees with me (and probably a good percentage of the rest of you do too) that the proper phrase is “WHEN Kepler discovers HOW MANY Earth-like planets there really are.”

    I bet the large majority of people reading this believe it’s inevitable that we will discover thousands of such worlds. Then we can target those worlds for spectrum analysis to see if there’s organic molecules. Those worlds we can target for increased SETI.

    Even if we just found an atmosphere that contained inorganic molecules created by intelligent industry it would be revolutionary.

    What if the atmosphere was full of plutonium? What if there were lots of atmospheres filled with plutonium…would we give up nuclear weapons? Mourn for civilizations we’d never know or hope for survivors? The implications for the kind of information that’s going to come from this are huge, and I’d never really thought of it past the purely scientific curiosity I had about the matter.

    Such a simple mission, so few people know about it, but in 3 years it’s almost certain to revolutionize the whole way we think about the universe. Just the fact that there are so many stars… probability says that we are almost certain to discover all that and more.

    We are on a clear path to being able to detect at least some level of alien life, which is virtually certain to exist. That this will almost certainly happen in my lifetime is amazing.

    Of course science is unforgiving, and if it turns out there’s just a few such planets then that will be interesting too. It’ll be nice to have a number no matter what it is. But I just bet that in 3 years time, we find out the number is something ridiculous. Something that will redefine how everybody in the world thinks about the cosmos. I can’t wait!

  59. ethanol


    5 years ago i figured we were decades from discovering earth-like planets. When I heard about Kepler I was amazed. This really is the golden age of extrasolar planet discovery.

  60. gopher65

    Great post. This is a topic that I find very interesting:).

  61. chief

    I assume that Kepler can detect not just from star/planet light transits but from star wobble as well. Although we couldn’t get small planet? detection, it should give an indication of planets around the star and do it with a better precision.

  62. Jack Mitcham

    I’m going to school for astrophysics, and in 2011 or 2012, I’ll be doing my senior undergrad research project. I wonder if I’d have access to any data from Kepler?

  63. Egaeus

    I knew what was coming as soon as I saw the second graph, and all I could think was, “no effing way….” That is beyond awesome. Congratulations to the team that designed such an awesome instrument.

  64. Dave

    One word: WOW!

  65. T.E.L.

    chief Said:

    “I assume that Kepler can detect not just from star/planet light transits but from star wobble as well. Although we couldn’t get small planet? detection, it should give an indication of planets around the star and do it with a better precision.”

    Not really. Kepler isn’t doing spectrometry, so it can’t detect the Doppler shift from wobbly motion. Kepler is dedicated for photometry.

  66. ethanol

    Here’s a question: could Kepler detect moderately out-of plane gas giants based solely on the change in phase? I suppose this only works for gas giants close enough to their star to be highly luminous.

  67. T.E.L.

    ethanol, that sounds plausible. I wouldn’t be surprised if it can even be adapted to identifying small planets, since Kepler is already geared to detect small bodies’ contributions to the light curve.

  68. tacitus

    Here’s a question: could Kepler detect moderately out-of plane gas giants based solely on the change in phase? I suppose this only works for gas giants close enough to their star to be highly luminous.

    Good question. I’m guessing that out-of-plane hot jupiters that can produce a slope as pronounced as HAT-P-7b will be detectable, but it wouldn’t be much good for the hunt for Earth-like planets since the phase changes would be lost in the noise.

    But I suspect they will be able to tease additional planets out of the data based on variations in the timing of each transit. That might be a more sensitive way to increase our burgeoning catalogue of planets. Exciting times indeed.

  69. Tim G

    Travis (#54),

    It looks like Scott R (#45) actually answered the question as to why the top of the big dip is higher than the bottom of the small dip: “…the planet is [extremely] close to the star, it is heated hot enough that it glows incandescently, thus the discrepancy is the glow from the planet’s night side before the transit.”

  70. Jess Tauber

    The surface area of the planet is not the same as the surface area that blocks the light. Everyone knows that, right?

    Jess Tauber

  71. Is it just me, or would this also enable us to spot large planets orbiting far from “edge on”? A large planet orbiting at say 45 degrees should give us a good reading of planetary phases, no?

  72. markogts

    Most astronomers, including me, assume that these planets exist

    [Ironic mode on]

    So why bother? Just plant a Church, the Church of “these planet existers”, and save the money of expensive instrumentation for some lobbying.

  73. michael4096

    If we can see planet phases from edge on transitions, surely we will be able to see them for non-edge on also? Perhaps only for big ones though as it seems to be at the sensitivity limit

  74. Stargazer

    Beyond awesome. And that’s what we as a civilisation should do, stop doing bad stuff and start being awesome full-time.

    Also, when I read about some new spacecraft or powerful telescope, I sometimes wish Kepler, Copernicus, Galilei and the other guys could be here to see what is possible in their future…

  75. Here’s a question: could Kepler detect moderately out-of plane gas giants based solely on the change in phase? I suppose this only works for gas giants close enough to their star to be highly luminous.

  76. Christina Viering

    I see galactic realtors as the next hot career.

  77. Eddy

    @Jason (#42)
    I assume that you can not use the same observations from Kepler to determine the size of the planet. However, once you know a planet is there, you can do follow-up observations to measure wobble with other instruments, perhaps even ground-based, since the difference in brightness is only important to detect the planet in the first place.

  78. Eddy

    @Bjørnar (#75)
    In that case, the tell-tale dips are gone and you would only see gradual change in brightness, so it is not as clear cut.

    You need to mark this as a maybe and do follow-up measurements.

  79. fropome

    “if we want to find an actual Earthlike planet we have to be patient. It takes the Earth a year to orbit the Sun, right? So suppose we see a small dip in the light from some star that indicates a planet the size of the Earth is orbiting it. To confirm that, we’d have to wait a year to see that dip again!”

    I might be being optimistic, but couldn’t we tell whether the planet was in front of the star or visa versa from the sinusoidal variations immediately before and after the dip? If the variation is at a high point then this will be because the planet was in increasing light (from our perspective) before being eclipsed, while if it’s at a low point then it’s because the planet was in decreasing light (again, from our perspective) before eclipsing the star.

  80. Matt

    @Jeremy (#17):

    Go to the Kepler website and read the research done by Bill Borucki (the Principle Investigator for the Kepler mission). There are all sorts of figures about the chances of detecting something edge on.

    And no, Kepler can not detect star wobble. But star wobble is not a useful means of finding Earth-sized planets. It is biased towards gas giants with small orbital periods. So despite this ability, the awesomeness of Kepler remains! 😀

    Man, I was just ecstatic when I heard this press conference. I work at the Laboratory for Atmospheric and Space Physics and get the honor of doing mission ops for Kepler. (In fact, I’m headed off to work in about half an hour to do just that… talk to Kepler!) Just to know that this sombeetch is working just as well as they had hoped is nice. It’s an expensive mission but well worth it. And actually, compared to the 4 others than I operate at LASP (ICESat, QuikSCAT, SORCE, and AIM), Kepler is the easiest to handle. We don’t talk to it much and it just sits there and stares… and stares… and stares… never blinking.

    The spacecraft itself is a piece of work. There should be a press release from Kepler’s launch laying around the internet somewhere; read it. This thing can maintain pointing accuracy of 9-milliarcseconds, 3-sigma over 15 minutes. Ridiculous.

  81. !AstralProjectile

    It keeps getting better. Kepler is providing a wealth of info that to me was unanticipated. Thanks to those who answered the question I asked, and many others I was thinking about. As Chief and others have asked, any comments on the pros/cons of using the phase technique compared with stellar wobble? I suppose yo9u could determine the color of big planets…

  82. Awesome! Must be great to be a part of the Kepler team.

  83. well good, this is good news, “we” are heading in the right direction, once we mapped out all the stars in this galaxy, we should start thinking about a faster than light propulsion system so “we” visit these star systems in the next 100 years!!!!!!!!!!!!!!!!!!!!!!!!!
    “pack your bags” and put on your seat belt!.

  84. Tom (H. Type)

    Great Post Phil,
    Kepler works!
    My major concern is that it will continue to work for the next 3-5 years. We have see Hubble service missions restore that space telecope to operation. Kepler in it’s orbit around the sun is currently 0 .02 AU away for Earth, just a teeny bit too far away for any help should the unthinkable occur.
    I know, I’m a big “downer”, my kids say that too…I need to work on that…

  85. Matt

    Actually, Kepler is about 0.1 AU away. Two-way light time is ~100 seconds as of today.

  86. ross

    humorously enough, purely out of coincidence, I was reading this article while listening to a song by the band “in flames” called “world of promises”. coincidolia?

  87. PaleGreenPantsWithNobodyInsideThem

    Phil, dude,

    The headline should read, “Kepler works, bitches!”

  88. @PaleGreenPantsWithNobodyInsideThem: Yeah. Need to get a t-shirt with that on the front and the light curve graph on the back.

  89. Caleb Jones

    @Christopher Ambler (about creationist museum being shut down for tax fraud)

    From the article:
    “He was found guilty in November 2006 on 58 counts, including failure to pay employee taxes and making threats against investigators.

    The conviction culminated 17 years of Hovind sparring with the IRS. Saying he was employed by God and his ministers were not subject to payroll taxes, he claimed no income or property.”

    From a Christian’s perspective, this is a shame. Sounds like he forgot about the teaching of Christ (Matthew 22:17-22):

    “Tell us therefore, What thinkest thou? Is it lawful to give tribute unto Caesar, or not?
    But Jesus perceived their wickedness, and said, Why tempt ye me, ye hypocrites?
    Shew me the tribute money. And they brought unto him a penny.
    And he saith unto them, Whose is this image and superscription?
    They say unto him, Caesar’s. Then saith he unto them, Render therefore unto Caesar the things which are Caesar’s; and unto God the things that are God’s.
    When they had heard these words, they marvelled, and left him, and went their way.”

    Interesting, isn’t it, how people selectively choose which teachings from their religion they will follow depending on how convenient it is for them? It’s like a scientist who only agrees with theories/laws/measurements that fit their particular view and reject all others.

    In both cases, it’s what happens when people but BEING right above discovering WHAT’S right.

  90. Matt

    @treelobsters (#93):

    The Kepler website sells tshirts with the star field and CCD array point of view on it… realllllllly nerdy. :p

  91. JoeZo

    A couple more bits of info from the NASA press release:

    The depth of the occultation and the shape and amplitude of the light curve show the planet has an atmosphere with a day-side temperature of about 4,310 degrees Fahrenheit. Little of this heat is carried to the cool night side. The occultation time compared to the main transit time shows the planet has a circular orbit.

  92. Gary Ansorge

    46. Steven

    Spitzer has a much better chance of answering that question, since a Dyson sphere/swarm would capture its suns radiation and what gets sent out to the universe is infrared, so if we find an intense infrared source, we can assume it’s either a lot of dust being solar irradiated or a Dyson swarm,,,we already have such observations, but I have no idea how we would differentiate between plain old dust and a D-Swarm.

    Gary 7

  93. Torbjörn Larsson, OM

    [orgasm of awesome] Yay! No, not enough, I’ll repeat: yay! [/orgasm of awesome]

    Lots more observational detail than I hoped to understand, thanks all.


    it just sits there and stares… and stares… and stares… never blinking.

    “When you look into an abyss, the abyss also looks into you.” [Friedrich Nietzsche]

  94. Michael Parmeley

    Doesn’t this type of planet detection only work for stars whose planets’ (if any) orbital plane happen to intersect the earth?

    So if we don’t detect planets around a star is it assumed it doesn’t haven’t any or do we know if we are looking at the north or south pole of the star? If we are looking at the north/south pole from our point of view the planet may never go behind the star. Right?

    Maybe a dumb question but I am not an astronomer:-)

  95. T.E.L.

    Michael Parmeley,

    That’s not a dumb question. The assumption is that the various planets’ orbital planes will be randomly distributed, so that some fraction of them are expected to be approximately edge-on to Earth.

    I don’t happen to know, but it’s possible that there already are some data on the distribution of orbital planes, culled from detections of distant gas-giant planets. Those planets have all be found by measuring the Doppler shifts of their host stars, and the Doppler data should be able to indicate the orbital planes’ inclinations to within some restricted spectrum of angles.

  96. Matt

    @Michael Parmeley:

    Yes, correct. Read some of the above posts for percentages of planets expected to meet this criteria.

    The Kepler science team did loads of studies about all sorts of this kind of thing. People sort of… don’t get it… that you don’t exactly get half a billion in funding if you haven’t done your homework yet.

    All the ideas or issues that people come up with — the Kepler science office has thought about. Don’t worry. They’re smarter than we are!


  97. brad

    re: dave@41 & don@44
    i believe our ecliptic is almost perpendicular to the galactic plane.

  98. Michael Parmeley

    @T.E.L. @ Matt, Thanks for the info!

    I wasn’t have any sort of delusions that I had thought of something that no one else had, I was genuinely curious on how many stars this type of observation would work for. :-)

  99. Gary Ansorge

    102. Michael

    A planetary transition doesn’t have to be across its suns equator. I expect it would have a blocking effect even if it’s orbit were inclined to us by as much as 45 degrees( of course, that would also depend on how close the planet was to its primary). Further up in the responses, there was one reference that stated perhaps 10 % of the observable solar systems would have planetary orbits close enough to edge on for us to observe such transitions.

    GAry 7

  100. Matt

    Hah, not many, right? That’s why they need a hundred thousand stars! 😀

  101. Steve A

    @Jack Mitcham #65

    Maybe, depends who your prof is and how available the data is. IIRC usually program scientists (or those who requested the object like with Hubble) have the first year of the data to themselves so they can publish first, and then its open to everyone. If you are lucky enough to know someone in the program, I’m sure they’ll be needing help getting through everyhing. BTW, having gone through this myself, now is the time to start finding projects you can work with. Also you might want to see about summer fellowships starting next year, especially in this stag of your career. You could get to work on data that way.

    Even if you don’t now, there will be so much data it’ll take years and years to get through it all, not to mention all the new, unintended finds as people develop innovative ways to look at the data or use it to answer new questions that no one has thought of now. What I love about anything space related is that every year seems to be the best year to be entering the field. Good luck!

  102. Scripp

    7. !AstralProjectile Says:
    August 6th, 2009 at 1:51 pm

    Very nice.
    However I havn’t figured out why the transit dip is so rounded at the bottom – I would have thought it would be squarer, like the other dip.

    The first dip might be rounded because only partial light was obscured and the second dip might be squared because the entire light source from the planet surface was obscured.

  103. andy

    Proof that online communities warp the mind… as a (former) member of deviantART, every time I see !AstralProjectile’s pseudonym, I assume this is a banned user from the initial ! symbol…

    Scripp: as has been mentioned upthread, rounding is due to limb darkening – basically the edge of the star’s disc appears dimmer because the grazing angle means optical depth of unity is achieved further up in the star’s atmosphere and hence at lower temperature regions.

    While most of the focus is on detection of Earth-sized planets, there are other phenomena associated with planetary systems that may potentially be accessible to Kepler: exomoons and ring systems for a start. Would be good to know whether the gas giants that are in very different situations to our solar system’s examples (e.g. eccentric orbits, inner system locations) are associated with these.

  104. John Sherman

    I’m as impressed with the comments as with the science behind the Kepler. Unlike comments elsewhere on the web there are no typos, mistakes of choice of word, or other signs of arrested development. What a wonderful indication of intelligence in our world. Don’t you ever comment on other news stories?

  105. Epic win. This is why spaceflight must continue.

  106. rosendo gregory rojas

    I fully believe we have left our purpose and responsibility of being close to earth on someone elses doorstep to hopefully be looked over, while we are running around trying to figure out if there are other Earths, when we very well know that there is. Hopefully, soon, there will be a mental shift towards something we as humans had, then, and finally realize our potential, now, which I think is to not stop change, but to adapt along with it. We, as the bible shows, adapted with the flood, the plague, many wars and death, and years of struggle; from the beginning of colonies to the freedom of slaves, still to this day with civil rights. But what is it about human nature that says we must: destroy to conquer, create fear to be respected and be completely separated to be connected?

  107. Gary

    Earth-SIZED (more or less), not necessarily Earth-LIKE. You’re letting your enthusiasm get away from you , Phil.

  108. dragonet2

    Our NASA channel is playing the video of Kepler right now, including the diagrams shown above,.

    I needed something that would make me smile (I could not afford to go to Worldcon and we’re back in the furnace here in KC, MO),

  109. coolstar

    Hats off to Bill Borucki, the PI on Kepler, and the father of the transit method for finding extrasolar planets. He stuck with this idea after NASA shot it down, time after time, for the better part of 30 years.
    The likelihood is that with this kind of precision, Kepler will detect many earth-like planets (in the sense of being roughly the same size and in the habitable zone) orbiting late K and M stars long before enough data has been collected to find earth-sized planets orbiting at around 1 AU around solar type stars. It’s also entirely possible that earth-sized moons will be found around Jovian-sized planets in habitable zones. And even RINGS around transiting Jovian planets. Precise timing of transits around the hundreds of hot Jupiters that will likely be found can also turn up non-transiting planets in those systems. Then there’s the astroseismology that will be done. The richness of the science that can be done with Kepler is really breathtaking.
    There’s a chance, probably at around the 10% level or smaller, that Dave Charbonneau’s M-Earth project to survey M dwarfs from the ground will beat Kepler to the punch in finding Earth-like planets. It’s nice to have lots of bright people working on such hard problems.

  110. Matt


    “The richness of the science that can be done with Kepler is really breathtaking.”

    Absolutely. The sheer amount of crap they can do with simple (and I use that term lightly) transit data is… astounding.

    Some of the coolest follow-up ideas I’ve heard about…

    -Using a second body, some tens of thousands of miles away from the imager, to occult the star and view the planet DIRECTLY. This would require a very intense orbit maintenance routine to keep the imager and the occulting body in orbital phase with each other.
    -Using an array of mirrors separated by a few kilometers to create an effectively HUGE telescope to separate the star’s light from the planet’s light, again to image the planet DIRECTLY.

    Anywho. Kepler is still rockin’ the casbah.

  111. Hasnor

    Comment retracted.

  112. GK4

    Does anyone here know how the stars and planets observed by this Kepler mission will be cataloged and designated? The Hungarian Automated Telescope network gives us the “HAT” in “HAT-P-7”. If Kepler’s abbreviation has been chosen, what is it?

    Thanks in advance if anyone can answer this.

  113. GK4, what I will tell you is not from any reliable source so…don’t trust me on it… :)

    I presume that the already known planets will keep their designation, in this case, the name planet we’re talking about remains the same: HAT-p-7b, the first planet discovered around the star HAT-p-7.

    If planets are discovered around stars not previously named that will be a different story, I presume that it will happen the same as with COROT, the first star will be named Kepler-1 and the eventual first planet around it will be Kepler-1b and on and on and on and on until Kepler-387e… 😉

    But, has I’ve said…don’t trust me on this… :)

  114. Darth Mewling

    Why are we wasting money on this? Who exactly is this helping? There’s a worldwide recession and we’re burning millions of gallons of fuel and burning thousands of manhours to do what now?

  115. Darth Mewling (#122): I assume you give all your money, time, and effort into solving all the world’s problems, right? You might want to read this.

  116. StephenG

    Another small step for man to ind our place in the universe

  117. T.E.L.

    Darth Mewling Said:

    “Why are we wasting money on this? Who exactly is this helping? There’s a worldwide recession and we’re burning millions of gallons of fuel and burning thousands of manhours to do what now?”

    The fuel is a drop in the ocean. If every drop of rocket fuel were diverted to the highways, it’d hardly make a dent. The man-hours are what we also calls “jobs” which pay people money. Tell you what: my parents spent their childhoods in states of poverty during the Great Depression, an economic collapse much worse than what’s happening today. Neither of them was able to finish school (and by school I don’t mean they had to abandon their PhD theses; I mean high school, because they couldn’t afford not to work). Yet neither of them is clueless enough to think that some things aren’t worth doing because they’re what we want to do to enrich ourselves.

    Haven’t you ever gone to the movies, read a book, played a game? What do those things do to keep people from starving in poor countries? People in the United States collectively spend billions every year to amuse themselves with movies, books, games, etc. I’ll bet right here & now that you’ve spent money on at least one movie this year ($8.00 just for the ticket; corn & soda = another $8.00 at the very least), and at least one book (ten bucks used from eBay or Amazon, much more brand-new). What’s your share of the national budget for space exploration? Something like $50 in taxes that you never even had in your pocket. So your share of NASA is roughly twice what you spent on one movie and one book. Did you see more than one movie? Read more than one book? How much have you spent on cable TV? How much on greasy sandwiches at McDonald’s? With a name like Darth, I’ll bet you’ve spent some sheckels on Star Wars. And the year isn’t even close to done yet.

  118. coolstar

    @Matt Check out Webster Cash’s Starshade idea at (this is the first mission you mentioned and is the most brilliant and original idea in astronomy in the last 20 years, IMNSH!).
    This deceptively simple idea killed the Terrestrial Planet Finder “mission” as soon as the first paper was given, basically, as it’s such a great idea.

  119. Charles J. Slavis, Jr.

    If there really is intelligent life out there shouldn’t we soon be receiving something similar to Gigabytes Island from out there? Or don’t they have HDTV yet?

  120. Mark

    It’s a little unfair to call HAT-P-7b an “unseen” planet when we’re seeing light from it.

    Also, consider me confused: in the 100x magnification graph, the observed brightness of HAT-P-7 when HAT-P-7b is behind it isn’t quite the observed brightness of HAT-P-7 immediately prior to transit: it is significantly lower, in a way that can’t be explained by the planet reflecting light from the star. What’s happening? Does HAT-P-7b emit some if its own light at wavelengths detectable by Kepler?

    Nevertheless, I’m impressed by Kepler’s ability to detect HAT-P-7b’s phases. That means that it is sensitive enough to detect planets even if we’re not seeing those planetary systems edge-on.

    I wonder if they’re releasing their data to the Systemic people at UC Santa Cruz? (See for more information.)

  121. Torbjörn Larsson, OM

    @ 128. Mark:

    Asked and answered a number of times in the thread, earliest answer #45.

    [Yes, the planet glows visibly in some areas. At ~ 2000 Celsius temperatures on the sun-locked side it darn better do!]

  122. 44. don Says:
    By the way, what are the naming conventions for planets orbiting other suns?

    I’m a little late to the party here, playing catch-up on the last several days of BA posts. But I get so excited when I actually know the answer to a question here, I’ve gotta reply!!

    Most commonly, exoplanets are signified as Star b, e.g., the planet orbiting star HD 209458 is called HD 209458 b. If another planet would were to be discovered around this star it would be called HD 209458 c, a third would be HD 209458 d, and so on.

    In some cases, however, the exoplanet designations refer not to the parent star, but the research program credited for its discovery. For example, planets detected by the Trans-Atlantic Exoplanet Survey (TrES), have been named TrES-1, TrES-2, etc.

  123. Andrew

    I can’t see if this is mentioned above, but presumably what matters for the width, profile and depth of the dips are the solid angles subtended by the star and the planet on the plane of the sky as observed from Earth (which Phil loosely called the surface areas), the extent to which one of those areas overlaps with the other (which also depends on the inclination and radius of the planet’s orbit) and the profile of the star’s (and the planet’s) surface luminosity (e.g. limb darkening, and phases of the planet).

    Do I understand correctly that Kepler will observe this star and many others simultaneously and continuously for a period of several years? Even so, the selection effects must be horrific – there are still only a handful of systems known with inclinations less than 80 degrees, or orbital radius more than a tenth of an AU. (Incidentally, the transcript and slides from a recent lecture at Gresham College on this topic are interesting – )

    It will keep some astronomers entertained trying to spot a signal in the many time series that Kepler will record – but very neat, nonetheless, to do this with 10 days of test data!

  124. Leonard J. Gauthier

    August 12, 2009 at 2:22 pm, PDT. NASA (Kepler) is publicly funded. The public should have a right to know immediately what Kepler is discovering. Two “safe mode events” have occurred recently causing delays in the downloading of science data from Kepler. This spacecraft has the ability to not only detect earth-like planets but also to detect oxygen (life) in an exoplanet’s atmosphere. Are these “safe mode events” in fact being fabricated to give the National Security Agency (or whoever) an opportunity to censor Kepler’s data?

  125. Leonard J. Gauthier

    August 19, 2009 at 11:44 am, PDT. A downlink of science data scheduled for July 20, 2009 from Kepler was delayed until August 20, 2009…tomorrow! I sure hope that downlink happens on schedule! Kepler is fascinating stuff! Some are saying discoveries of earth-like planets by Kepler won’t happen for at least a couple of years!!? Why not!? Kepler, I thought, has the ability to do it now! Couldn’t we all discover tomorrow that our galaxy is teeming with inhabited planets?

  126. Leonard J. Gauthier

    Kepler began its’ search for exoplanets on May 12th. It collects and stores data and sends it back to earth once per month. It had a “safe mode event” on June 15th, sent (or downloaded) data on June 18th, had another “safe mode event” on July 2nd, was scheduled to download data on July 20th but didn’t, and yesterday it sent data again. I imagine powerful supercomputers are used to analyse Kepler’s data. So far, in three months of trying, Kepler hasn’t found anything…not so much as one transitting exoplanet! I know I’ll be heckled for saying it, but: I’m mildly suspicious. On May 12th the Kepler website announced that the “exciting” search for exoplanets had begun.

  127. Leonard J. Gauthier

    Message to Roger Hunter, Kepler Space Telescope Mission Manager, NASA Ames Research Centre: “Roger Hunter, there’s something you’re not telling us!”

  128. George B.

    What are the naming conventions for moons, in orbit around planets orbiting other suns?

  129. Leonard J. Gauthier

    I don’t know what the naming conventions for moons orbiting other planets are but somebody better find out because I hired Jenny Jamieson to make Roger Hunter talk…and if she succeeds (I’m sure she will), I think humanity will have great need not only for the naming conventions for moons, but earth-size planets too! Great need!

  130. Leonard J. Gauthier

    Another safe-mode event occurred November 14th. Mr. Hunter has said (shortly after announcing this latest SME) that NASA has budgeted for upwards of 12 safe-mode events per month! It’s been 6 1/2 months now since Kepler’s search began and still no discoveries of exoplanets…when Kepler during it’s 42 months of operations was expected by many to discover 100’s of exoplanets, including many earth-size exoplanets, and possibly oxygen in the atmosphere of several exoplanets. These safe-mode events seem to keep happening just before data was scheduled to be downloaded…almost like somebody wanted “to have a look at it first”! Is it just me thinkin’ somethin’ ain’t right here?

  131. Leonard J. Gauthier

    Phil, you’re an astronomer…you’ve worked with Hubble. Tell me something’s not right here! I keep hearing,”Kepler’s not discovering anything yet because it’s just so difficult!” Phil…IT’S BEEN EIGHT MONTHS!!! In my mind Kepler’s primary function is not to discover ESE’s (earth-size exoplanets), it’s to discover exoplanet-oxygen, something Kepler can apparently do if oxygen is out there. Oxygen is produced by life…and only by life. Washington doesn’t allow the free-flow of information out of war-zones…are we being a little naive to suppose that a free-flow of info out of Kepler is being allowed? Kepler represents the first time in history that humanity has had “eyes”. Things are going to change inside the collective-subconscious of the human-race once we discover with certainty that there’s hundreds of millions of inhabited planets out there; Washington will look less intimidating, for one thing. Any chance you could give Roger Hunter a call, Phil, and ask him if any of Kepler’s data has indicated any trace at all of exoplanet-oxygen yet?

  132. Leonard J. Gauthier

    Of course, Phil, if there are millions of inhabited exoplanets in our galaxy and we can see the oxygen in the atmospheres of some of them, there’s a good chance some of them can see the oxygen in our atmosphere! To digress: why is your website called, “Bad Astronomy”? If you worked on Hubble for 5 years, you gotta be a good astronomer.

  133. Aathira

    I’m eagerly waiting to move to Kepler 22b with my family. Regards to Kepler Telescope on it’s mission.


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