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What type of life could appear on this world

  1. Jun 8, 2013 #1
    Star G2
    Planets name Athena
    Planets Diameter 0.50 Earths, Mass 0.125, Density 5.52 g cm/3
    Planets orbit 1.10 au with an eccentricity of 0.08
    Planets axil tilt 20 degrees
    Planets rotation rate 24 hours
    Planets water/land ratio 60/40 with an average ocean depth of 18,000 feet.
    Planets atmosphere 0.30 bar of 67% nitrogen, 30% oxygen, 2% Carbon dioxide 0.5 argon
    Planets age is 4 billion years
    Planets temperature is 285 K
    The core is molten still and the planet has a magnetic field and is currently geologically active with volcanoes erupting on a daily basis.

    It has 1 moon with a radius compared with Athena is 0.25 with a density of 3.57 g cm/3
    The moon orbits 200,000 km from Athena's surface with an eccentricity of 0.053

    I am wondering what type of life could appear on such a small world with these parameters for a short book im writing.
    Last edited: Jun 8, 2013
  2. jcsd
  3. Jun 8, 2013 #2


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    Staff: Mentor

    Looks like a smaller version of earth. The lower surface gravity allows larger animals/plants.
    I would not expect so much volcanic activity.
  4. Jun 8, 2013 #3
    As far as the volcanic activity I wanted the planet to have a hot dense highly radioactive core for the planets size. There are only about 250 active volcanoes on the planet that have erupted in the last 10,000 years and only dozen are constantly active with eruptions like Kilauea and Stromboli. The larger more moderate eruptions occur once every 1-3 months so that the atmosphere is replenished. This is still much less activity than Earth has. I realize that the planet is small but the frequent volcanic eruptions replenish the atmosphere with enough gases so it remains if that makes sense.
    Last edited: Jun 8, 2013
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