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Astronomers Find Smaller Extrasolar Planets
SABME writes "NASA has announced the discovery of a new class of extra-solar planets. Here's a link to the NASA news release. These planets are only 10-15 times bigger than Earth; how far off are we from discovering Earth-sized planets orbiting other stars? Future NASA missions aimed at broadening these discoveries include Kepler, the Space Interferometry Mission and the Terrestrial Planet Finder. More info available at NASA's Extrasolar Planets webiste.
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All they detected is that it looks like the suns in question have something spinning around them. When they actually photograph them or detect the planets themselves THEN and only then can we start to speculate what they look like. For now it is pure speculation that they are in fact planets.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
Yes, but are they Class M?
M
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Class M
From Memory Alpha, the free Star Trek reference.
In Planetary Classification a Class M (known as the Minshara class in the mid-22nd century among Vulcans) planet is a 'Terrestrial' planet. They have an age that ranges from 3-10 billion years and a diameter between 10,000 and 15,000 km. They are located within the Ecosphere of a Solar System. A Terrestrial planet is catagorized by an abundance of surface water (however, if this amount goes above 80% the planet is considered a Class O or P) and an atmosphere high in nitrogen with oxygen and trace elements. Life is often abundant on Class M planets; they contain extensive vegetation, animal life and often have native humanoids.
Examples of Class M planets include: Earth (Sol III), Vulcan, Cardassia Prime, Bajor, Romulus and Qo'noS.
http://www.memory-alpha.org/en/index.php/Class_
The NYT article doesn't say the planets are smaller than neptune or jupiter, as the NASA article does, but neither article explains why these planets are signs of Earthlike planets. Can someone fill me in?
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Before they find a genuinely earth-like planet with this technique - with the radial velocity technique you find big close planets first, later big distant planets and medium-sized close planets, etc., and small close but not too close planets last. Not a criticism of the astronomers; it's amazing that they can find even a very close Neptune-sized planet with this. . .
On such a planet, albeit one not so close to its star as the ones they have found so far, it is easy to imagine creatures walking on stout legs -- never mind the insects and sea creatures that wouldn't even notice the "extra" weight.
"These planets are only 10-15 times bigger than Earth"
Why do we assume that life is most likely where gravity is close to ours?
Consider the organisms discovered only in the last 30 years,
which thrive in environmental extremes of heat and pressure.
And it need not be non-"intelligent" life:
consider the pressures sustained by sperm whales and giant squid.
For that matter, is it guaranteed that large diameter = crushing gravity?
Might there realistically be a planetary giant with significantly lower density?
Or might crushing gravity be reduced by the gravity of surrounding bodies,
e.g. moons or binary/ternary stars,
or by a single star orbited by a non-rotating planet?