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narrator
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Hi, not sure if this belongs here or Astrophysics or... ??
http://au.news.yahoo.com/amazing-stories/a/-/article/9454275/could-exoplanet-be-a-haven-for-life/" [Broken], planet Gliese 581d. Sorry if this is old news, though the report is in today's Yahoo news here in Oz.
They say the planet probably has about twice Earth's gravity, and probably has water. Fictional stories sometimes talk about planets with greater or lesser gravity than Earth, but not double, which makes me wonder if they approach it too simplistically. With 2G, life forms (if they exist) are likely to be flatter and evolved to deal with what would be natural gravity to them. But surely the additional gravity would create geological and environmental problems that would go against sustaining life.
The interesting thing though is the new modelling for finding such planets. Under the old modelling, the article said there was a mistaken planet Gliese 581g, which the new method proved wrong.
From the science shows and articles I've watched and read, they say the two aspects for discovering and analyzing these planets are the gravity effect of the planet(s) on their star and when they're lucky enough to see one cross the face of the star. A really good science show demonstrated just how difficult the that is. Are there other aspects apart from these two?
I have difficulty comprehending how accurate the "wobble" method could be. At such distances, wouldn't it be like watching a ball-bearing move less than a hair's width, when that ball-bearing is as far away as the moon? Also, the star could have several planets, like ours, making such wobbles difficult to interpret, let alone see. And lastly, is our own "wobble" effect from our sun, moon and planets taken into account in such calculations?
Fascinating stuff anyway. Drivers, start your FTL's.
http://au.news.yahoo.com/amazing-stories/a/-/article/9454275/could-exoplanet-be-a-haven-for-life/" [Broken], planet Gliese 581d. Sorry if this is old news, though the report is in today's Yahoo news here in Oz.
They say the planet probably has about twice Earth's gravity, and probably has water. Fictional stories sometimes talk about planets with greater or lesser gravity than Earth, but not double, which makes me wonder if they approach it too simplistically. With 2G, life forms (if they exist) are likely to be flatter and evolved to deal with what would be natural gravity to them. But surely the additional gravity would create geological and environmental problems that would go against sustaining life.
The interesting thing though is the new modelling for finding such planets. Under the old modelling, the article said there was a mistaken planet Gliese 581g, which the new method proved wrong.
From the science shows and articles I've watched and read, they say the two aspects for discovering and analyzing these planets are the gravity effect of the planet(s) on their star and when they're lucky enough to see one cross the face of the star. A really good science show demonstrated just how difficult the that is. Are there other aspects apart from these two?
I have difficulty comprehending how accurate the "wobble" method could be. At such distances, wouldn't it be like watching a ball-bearing move less than a hair's width, when that ball-bearing is as far away as the moon? Also, the star could have several planets, like ours, making such wobbles difficult to interpret, let alone see. And lastly, is our own "wobble" effect from our sun, moon and planets taken into account in such calculations?
Fascinating stuff anyway. Drivers, start your FTL's.
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