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Astronomers Detect Planetary System Similar To Our Own

Posted by Soulskill on from the maybe-it-has-oil dept.

littlesparkvt writes "A team of astrophysicists at the German Aerospace Center (Deutsches Zentrum für Luft und- Raumfahrt; DLR), together with German and European colleagues, has discovered the most extensive exoplanetary system to date. Seven planets circle the star KOI-351 – more than in other known planetary systems. They are arranged in a similar fashion to the eight planets in the Solar System, with small rocky planets close to the parent star and gas giant planets at greater distances. Although the planetary system around KOI-351 is packed together more tightly, it provides an interesting comparison to our cosmic home."

13 of 54 comments (clear)

  1. Packed together tightly is misleading by Anonymous Coward · · Score: 5, Interesting

    All seven planets in the system are inside Earth orbit -- which may lead you to believe they're packed in tight. But one AU is 149,597,870,700m.

    The interesting thing is that this means that several of the planets could be inside the habitability zone (KOI-351 is a class G, just like the Sun, and only slightly hotter).

    1. Re:Packed together tightly is misleading by Anonymous Coward · · Score: 4, Funny

      Are you saying that this system is packed normally, and it is our solar system which is unusually loose?

    2. Re:Packed together tightly is misleading by Ihlosi · · Score: 2, Informative
      If they can detect an oxygenated atmosphere on one of them, that's a sure sign of life right there.

      Um no. Life doesn't have a monopoly on splitting oxygen atoms off other compounds (CO2, H2O) - simple photolysis can do the same thing.

    3. Re:Packed together tightly is misleading by gravis777 · · Score: 2

      Actually, that could be a possibility. As this is the most extensive exoplanetary system discovered to date, we do not have enough data to really determine what is "normal". However, quite a few of the exoplanets I have been reading about do orbit their star pretty closely (although I would say I haven't even looked at 5% of the 1000 exoplanets out there).

      It is a feasable theory to say that our planetary system is unusually loose, however, until we have more data on more systems, its impossible to say.

      A bit more serious - does anyone know if the habitable zone is the same regardless of star size (ie the futher you are from the star, the more heat disipates, regardless of star size?). Just wondering. It seems logical that planets in a smaller star would be more tightly packed together and planets around a larger star are more loosly packed together, but I do not know enough about that. Can someone shed some light on that?

    4. Re: Packed together tightly is misleading by DigiShaman · · Score: 4, Insightful

      In the vast quantities we now have on Earth? Not on this planet at least. The Great Oxygenation Event was caused and maintained by life 2.4 billion years ago.

      Cyanobacteria, which appeared about 200 million years before the GOE, began producing oxygen by photosynthesis. Before the GOE, any free oxygen they produced was chemically captured by dissolved iron or organic matter. The GOE was the point when these oxygen sinks became saturated and could not capture all of the oxygen that was produced by cyanobacterial photosynthesis. After the GOE the excess free oxygen started to accumulate in the atmosphere. -wiki

      --
      Life is not for the lazy.
    5. Re:Packed together tightly is misleading by invid · · Score: 2

      However, quite a few of the exoplanets I have been reading about do orbit their star pretty closely (although I would say I haven't even looked at 5% of the 1000 exoplanets out there).

      It is easier to detect planets with tight orbits because you don't have to look at it very long to see that there is a planet. For an alien to detect Earth, they would have to observe Sol for a year. For them to detect Jupiter, they would have to observe Sol for 12 years.

      --
      The Moore-Murphy Law: The number of things that will go wrong will double every 2 years.
  2. Germans AND Europeans? by ScentCone · · Score: 5, Funny

    Is that like working with a team of Canadians and also some North Americans?

    --
    Don't disappoint your bird dog. Go to the range.
    1. Re:Germans AND Europeans? by Frosty+Piss · · Score: 2

      Is that like working with a team of Canadians and also some North Americans?

      Well, the Canadians could be from Quebec...

      --
      If you want news from today, you have to come back tomorrow.
    2. Re:Germans AND Europeans? by gravis777 · · Score: 2, Funny

      Are you saying there is something in America OTHER than the USA? Whoa, you need to get that commie mindset out of here! Go back to Japan, you commie!

      (Yes, I know Japan is not communist, you would just be surprised how many people are out there who thing anything that is not "America" is communist)

  3. Similar to our own.... by Anonymous Coward · · Score: 5, Informative

    Title is a bit misleading. The star is pretty close (based on temp and size, but no spectral type), yes, but all the planets are WAAAAAAAAAAY too close to it to be anywhere near habitable. The ones farther out are Jupiter sized...

    Two of the planets closer in are a bit bigger than earth, but at orbital periods of 58 and 8 days, they're a bit too hot for my taste.

    tl;dr, the qualifier " packed together more tightly" is a little bit more important than what the summary suggests

    1. Re:Similar to our own.... by Ihlosi · · Score: 2, Insightful
      The ones farther out are Jupiter sized...

      As far as we know, Jupiter-sized planets usually have moons.

    2. Re:Similar to our own.... by gravis777 · · Score: 2

      Two of the planets closer in are a bit bigger than earth, but at orbital periods of 58 and 8 days, they're a bit too hot for my taste.

      If I am reading the chart right, there are two planets that are about 3x larger than earth, with orbital times of 121 days and one at 91 days. I can't tell from the chart if the planets are gas or rock, but given that the star is about the same size.... The one orbiting at 121 days would be around the same orbit as Mercury. Given that Mercury does have a thin atmosphere, it is possible that a planet of this size at this distance could support life, although if it does, I am sure they would look nothing like us (we would probably still cook).

      The planets futher out have orbits of 210 and 331 Earth days, but are 8.1 and 11.3x larger than Earth. However, if they had moons....

  4. But do they follow Titus Bode's law? by 91degrees · · Score: 2

    It's always intrigued me that planetary distances (if you include Ceres) follow so neatly to a logarithmic pattern. I wonder if this is something unusual in the solar system.