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Exoplanet Camera Now Online

The Bad Astronomer writes with news that the Gemini Planet Imager is officially online "The Gemini Planet Imager is a camera that is designed to take direct photos of exoplanets, alien worlds orbiting other stars. In a test run last November it spotted the exoplanet Beta Pictoris b, a dusty ring around a nearby star, and even snapped a portrait of Jupiter's moon Europa. Up to now, only about a dozen exoplanets have been directly imaged; GPI is expected to find dozens more in the next few years." From the Gemini project: "'Even these early first-light images are almost a factor of 10 better than the previous generation of instruments. In one minute, we are seeing planets that used to take us an hour to detect,' says Bruce Macintosh of the Lawrence Livermore National Laboratory who led the team that built the instrument." The announcement has pictures.

47 comments

  1. Oh! Sure.... by camperdave · · Score: 3, Funny

    Oh! Sure. They can take images of planets light years away, against the light pollution of the planet's sun, but somehow they don't have the resolving power to image the license plate on the lunar rover to silence the moon landing deniers.

    --
    When our name is on the back of your car, we're behind you all the way!
    1. Re:Oh! Sure.... by Anonymous Coward · · Score: 0

      Pssh, that's because you'd see the New Mexico state decals

    2. Re:Oh! Sure.... by Anonymous Coward · · Score: 5, Insightful

      Oh! Sure. They can take images of planets light years away, against the light pollution of the planet's sun, but somehow they don't have the resolving power to image the license plate on the lunar rover to silence the moon landing deniers.

      They would just claim that the pics of the landing sites were photoshopped so why bother entertaining their delusion?

    3. Re:Oh! Sure.... by jhumkey · · Score: 0

      And my mod points just expired yesterday . . . sigh.

      --
      No, I don't remember your name. But the memory mapped screen on a TRS80 from 1977 is from 15360 to 16383 if that helps.
    4. Re:Oh! Sure.... by Anonymous Coward · · Score: 0

      1 AU separation at 10 light years away is about 330 milliarcseconds, while 1 meter at the distance of the moon is about 0.5 milliarcseconds. For example, the test planet they name in the summary was separated from the parent star by about 450 milliarcseconds.

    5. Re:Oh! Sure.... by iggymanz · · Score: 1

      there is such a photo, taken at the site where they faked the landing. 8D

    6. Re: Oh! Sure.... by Anonymous Coward · · Score: 0

      ...and your point is ? Because I don't know how to decipher what you said there. Please explain...

    7. Re:Oh! Sure.... by Anonymous Coward · · Score: 0

      1 AU separation is enough to see an exoplanet, but to image it you need something closer to 10,000km resolution.

    8. Re: Oh! Sure.... by Anonymous Coward · · Score: 1

      A milliarcsecond is a unit for measuring very small angles, e.g. how far apart things are in the sky. This can also be a measure of the resolution of a telescope: the smallest angle of separation between two objects that show up as separated in the telescope. There are other factors at play and some details about exactly what is resolvable by a telescope, but the obvious point is that seeing the surface of the moon from Earth with 1 meter detail requires nearly a thousand times the bare minimum resolution needed to see something like the planet mentioned in the summary. Things on the scale of planet orbits comparable to the orbits of planets in our solar system, even at a distance of tens of light years, look much bigger than something about a meter in size on the surface of the moon.

    9. Re:Oh! Sure.... by camperdave · · Score: 1

      Fine, except they're not imaging 1AU diameter planets that are a mere ten LY away. They are imaging Jupiter sized planets at 63 light years away. Using the data from wikipedia (Jupiter's radius*1.65)/ (distance to Beta Picrotis B) = X/(distance to the Moon), they should be able to resolve objects with a radius of about 5 cm. In other words, Armstrong's bootprint should be a pixel or two across.

      --
      When our name is on the back of your car, we're behind you all the way!
    10. Re:Oh! Sure.... by cusco · · Score: 3, Funny

      Someone had convinced one of my co-irkers that the original Apollo 8 'Earthrise' image was Photoshopped (I'm **hoping** as a joke). He seemed surprised to hear that Photoshop didn't exist in 1968.

      --
      "Think about how stupid the average person is. Now, realise that half of them are dumber than that." - George Carlin
    11. Re:Oh! Sure.... by Anonymous Coward · · Score: 0

      Look at the image they are talking about of the planet, there are only about 25 pixels between the planet and the star, which is separated by about ~ 8 AU at the time. That works out to about 50 million kilometers per pixel, and from the size of the planet, each pixel is probably a bit smaller than the actual resolving power of the telescope. To see a planet, you only need enough resolution to see that there is a gap between the star and the planets. It doesn't matter that the planet is much smaller than the size of a pixel or the resolution of the telescope, as long as there is nothing else too close, it will appear as a distinct dot. If you want to map out features of the planet directly, then yes, you need much smaller resolution, but that is not what they are showing here.

      So using the example linked in the summary, you instead get 50 million km / 63 light years = X / 384000 km giving that a pixel 32 meters. From the looks of the image, the point spread function makes the actual usable resolution worse than that. This is far worse than the Lunar Reconnaissance Orbiter at less than a meter per pixel, which was able to already take some images of landing sites.

    12. Re:Oh! Sure.... by Anonymous Coward · · Score: 0

      That is all they are talking about doing, is seeing an exoplanet, not resolving details on the surface (short of tricks like using the changing direction of illumination to get some detail). It looks like they are using a 8 m telescope to image in the near infrared, so diffraction will limit them to a resolution of about 50-100 million kilometers at a distance of ~60 light years. Even if you could get an interferometer setup between two telescopes 100 m apart and play the same light blocking tricks to block the star, you would still be limited to a resolution of about 5 million kilometers.

    13. Re:Oh! Sure.... by Anonymous Coward · · Score: 0

      If that's true then they should call it the "Gemini Exosystem Imager", and reserve the term "Exoplanet Imager" for something that can resolve details on the surface.

    14. Re:Oh! Sure.... by camperdave · · Score: 1

      Except you're not taking into account the angle of the plane of the orbit, or where in the orbit the BetaPicB was at the moment the image was captured. This means that there is a significant cosine factor missing from your calculation.

      Actually, you can't tell anything from the picture, because there's no scale. Is the 25 pixel blob 1.65*Jupiter? Is the solar "blackout" disk 1.8 solar radii? Is the distance from the center of the blackout disk to the center of the blob 8 AU or 1, or something else entirely? There's no way of telling.

      --
      When our name is on the back of your car, we're behind you all the way!
    15. Re:Oh! Sure.... by Anonymous Coward · · Score: 0

      Except you're not taking into account the angle of the plane of the orbit, or where in the orbit the BetaPicB was at the moment the image was captured. ?

      From the post you replied to: ...which is separated by about ~ 8 AU at the time..

      There's no way of telling.

      Yeah, there is, you look up information on the discovery and orbital determination of Beta Pictoris B , and see that it is a near edge on system, with maximum separation occurring around 2013.

      s the 25 pixel blob 1.65*Jupiter?

      A not so subtle hint is the article saying the blackout disk includes the star, so the, so it should be much closer to the orbit size than the planet size. Nonetheless, ignoring that, and all of the info on the orbit of the planet, if the pixel size was anywhere near the size of Jupiter's diameter, that would be much, much bigger news considering it would mean the telescope is resolving things a factor of a 1000 times smaller than the diffraction limit...

    16. Re:Oh! Sure.... by Anonymous Coward · · Score: 0

      The lunar rover has no license plates. It was bought from a stolen vehicle peddler in Tijuana, original owner unknown.

    17. Re:Oh! Sure.... by Kyont · · Score: 1

      +1 for introducing the term "co-irkers" to my permanent working vocabulary! :-)

      --
      You shall see a cow on the roof of a cotton house.
  2. Rude gestures from other worlds by TWiTfan · · Score: 4, Funny

    One of the first pictures we snapped was of a totally unnecessary gesture from a very impolite world in the Andromeda region.

    --
    The cow says "Moo." The dog says "Woof." The Timothy says "Thanks, valued customer. We appreciate your input."
  3. RECEIVING MESSAGE...JUST A MOMENT by CarlStanley · · Score: 1

    All These Worlds Are Yours Except
    Europa
    Attempt No
    Landing There
    Use Them Together
    Use Them In Peace

    1. Re:RECEIVING MESSAGE...JUST A MOMENT by wonkey_monkey · · Score: 4, Funny

      Burma Shave.

      --
      systemd is Roko's Basilisk.
  4. Re:NSA by i+kan+reed · · Score: 0

    It's pretty much the only undeniably bad thing Obama has a personal responsibility for, so anyone with a political axe to grind has to bring it up. And it's not like my thinking Obama was better than any other viable choice makes the NSA thing defensible in any way, shape, or form.

    But yeah, someone managed to drag the NSA into a super-volcano discussion the other day, so, please, stick to security, us politics, and similar subjects for tired old discussions, please. There's plenty. We haven't forgotten that it's shitty.

  5. Cheese by tedgyz · · Score: 1

    Just tell me where the cheese is.

    --
    "No matter where you go, there you are." -- Buckaroo Banzai
  6. Disappointed by Anonymous Coward · · Score: 0

    Read the title and was expecting more like a update-every-30-sec type webcam with green men...

  7. International project by tomhath · · Score: 1
    FTFA:

    GPI is an international project led by the Lawrence Livermore National Laboratory (LLNL)

    Good to see international cooperation on a project like this. No reason for the US to go it alone.

  8. Re:We should be using this for near Earth objects by Urkki · · Score: 1

    I doubt it would work very well. Near earth objects would be moving fast, and be at unknown location, while this is designed to look at steady known object with really long exposure time and probably very narrow field of view.

  9. Breathtaking by argStyopa · · Score: 4, Interesting

    Well done, GPI team.

    I don't know about you, but for me this is absolutely thrilling. We're no longer inferring the existence of other planets, we're actually LOOKING at them.

    The word "breathtaking" doesn't cover it.

    And from a ground-based camera...I knew imaging tech is leaping ahead, but this makes me absolutely excited to see what the GPI (and eventually, hopefully, the JWST) will see over the next years.

    --
    -Styopa
    1. Re:Breathtaking by Koyaanisqatsi · · Score: 2

      This is a very interesting moment in time. At this rate of development, it is quite possible that in a decade or two we'd have full spectrographic analysis of the atmospheres of a handful of words. This might not be the ones best suited to sustain life, but we might get to those as well. Can't wait!

    2. Re:Breathtaking by bill_mcgonigle · · Score: 2

      And from a ground-based camera...

      Oh, wait, what?! And here I was remarking that the image of Europa was fantastic for an Earth-orbit telescope.

      I'll see your 'breathtaking' and raise you one 'astonishing'.

      --
      My God, it's Full of Source!
      OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
  10. How far we've come by wjcofkc · · Score: 4, Interesting

    The first exoplanet found orbiting a main sequence star was discovered on 6 October 1995, around 51 Pegasi. http://en.wikipedia.org/wiki/51_Pegasi

    It was only detected by gravitational wobble. Prior to that psuedo-exoplanets had been discovered but they involved non-solar system type objects such as pulsars. After the 1995 discovery, scientists slowly made more discoveries based on planetary wobble. At that time, the ability to take pictures like what we have seen in this article seemed farther flung into the future than we are now - if possible at all. But science is persistent and new technologies were developed fast. Now here we are imaging planets as they orbit their stars and the technology to image them continues to accelerate and advance at breakneck speed. If the development of scientific instruments were a race, planet finding and the LHC would at least be neck and neck if not having planet find slightly in the lead. There is preliminary work going on that promises views of extrasolar planets at resolutions as high as viewing the moons of the outer planets with our best telescopes - some say it may be possible to image planets with the resolution of looking back at the Earth from the moon. Is there no obstacle to discovery science cannot overcome? Time will tell. These new ultra-resolution planet find tools are hoped to be developed and ready by 2025, When I consider how far we have come and fast fast, I am inclined to believe we may actually get those images in that timeframe - despite how far fetched that kind of resolution may seem today.

    --
    Brought to you by Carl's Junior.
  11. Re:NSA by i+kan+reed · · Score: 1

    That was bad, but, come on, it was newly released software. Have you never been spared using a v0.X of anything?

  12. Online? by mrego · · Score: 1

    Oh, by online they mean plugged in. Not online as in accessible to anyone via the internet, right?

  13. Beta Pectoris? by fredrated · · Score: 1

    You mean it has muscles?

  14. Can't wait for more pixels by InfiniteLoopCounter · · Score: 1

    These pictures are 6px by 6px. With 30 or so pixels squared you can start to really make out stuff. Compare to our recent Juno probe's view of the Earth Moon system as it passed us on it's way to Jupiter (it will go past us twice).

    1. Re:Can't wait for more pixels by Anonymous Coward · · Score: 0

      Not happening. On that picture the planet is 0.001 px wide. The 6px by 6px blob you see is just overexposure.

    2. Re:Can't wait for more pixels by Anonymous Coward · · Score: 0

      The pixels are smaller than the actual resolution of the telescope, and the point spread function is just smearing the light from the entire planet over several pixels. You would need pixels and resolution several thousand time smaller to see distinct details from the planet, which would require a telescope much larger due to diffraction limits. Although if the planet rotates and is not tidally locked, you can get some detail from knowing different sides of it will be lit up in different pictures.

    3. Re:Can't wait for more pixels by InfiniteLoopCounter · · Score: 1

      The pixels are smaller than the actual resolution of the telescope, and the point spread function is just smearing the light from the entire planet over several pixels. You would need pixels and resolution several thousand time smaller to see distinct details from the planet, which would require a telescope much larger due to diffraction limits.

      Yes, I know. What we could do with is a space based telesope array better than the James Webb, which is yet to be launched. This would remove some of the problems with single lens size limits and light interference if we put it in a good observation spot.

    4. Re:Can't wait for more pixels by Anonymous Coward · · Score: 0

      Unfortunately, most of the space based interferometer projects have been canceled, and there would still be a lot of development work to do to make sure it is viable for larger arrays. The first generation, based on previous proposals, would only have a baseline of about 500 m and operate with borderline far infrared. That would still be stuck at ~1 million km resolution in a near by 10 light year system. We would need something on the order of a few kilometers at a lower wavelength of light to begin to get a few pixels of resolution of the nearest Jupiter sized planets. A few tens of kilometers would get us a bit more detail or a look at a much larger number of known exoplanets. Probably what most people would want/expect for an "image" of a planet would require improving it into the visible range and having interferometer over hundreds or thousands of kilometers.

  15. Re:NSA by InfiniteLoopCounter · · Score: 1

    It's funny, but the NSA actually has the best telescopes and has donated some of their old ones to NASA.

  16. Re:We should be using this for near Earth objects by Anonymous Coward · · Score: 0

    There are already several purpose built telescopes doing automated surveys for near earth objects. While there is still a ways to go for smaller objects, they do cover the full sky enough to now estimate some statistics on how likely it is we missed something doomsday sized, instead of just assuming we have no idea how much is out there.

  17. oh just that by Anonymous Coward · · Score: 0

    I thought this was a live webcam showing planets. maybe behaving badly.