The Meridiani Journal

Comment on Curiosity rover ready to start drilling again by 171. Carnival of Space – 302

2013-05-22T11:09:32Z

[...] back to work The Meridiani Journal tells how the Curiosity rover ready to start drilling again after just coming out of its month-long [...]

Comment on Curiosity finds odd ‘bubbles’ by Curiosity rover completes second drilling at 'Cumberland'

2013-05-22T00:11:36Z

[...] for habitable conditions in this area a long time ago. Cumberland, however, has more of the odd nodules on its surface which kind of look like little “blisters” or “bubbles.” The [...]

Comment on Curiosity rover finds ancient Mars was suitable for life by Curiosity rover completes second drilling at 'Cumberland'

2013-05-22T00:11:36Z

[...] to John Klein, and scientists are hoping to repeat the same results obtained at John Klein, which provided strong evidence for habitable conditions in this area a long time ago. Cumberland, however, has more of the odd nodules on its surface which kind of look like little [...]

Comment on Inspiration Mars: manned flyby mission planned for 2018 by Humans 2 Mars conference discusses manned NASA mission by 2030

2013-05-09T03:44:20Z

[...] humans to Mars, but there are others who want to do just that as well. As previously reported, the Inspiration Mars organization wants to send two people to the Red Planet by 2018. They would orbit the planet and [...]

Comment on The ‘red rose’ of Saturn: stunning new colour images of giant hurricane by R & J Thacker

2013-05-07T01:32:37Z

absolutely beautiful !!

Comment on There’s a lot of water in Jupiter’s atmosphere, thanks to comet impact by Carnival of Space 299 | SkyNet Chronicles

2013-04-29T06:01:19Z

[...] The Meridiani Journal – There’s a lot of water in Jupiter’s atmosphere, thanks to comet im… [...]

Comment on Three new possibly habitable ‘super-Earth’ planets discovered by Tony Trenton

2013-04-24T19:45:42Z

Many thanks for your help

Comment on Three new possibly habitable ‘super-Earth’ planets discovered by Torbjörn Larsson, OM

2013-04-24T19:10:15Z

Oops. I meant that surface gravity goes as ~ r, naturally.

Comment on Three new possibly habitable ‘super-Earth’ planets discovered by Torbjörn Larsson, OM

2013-04-24T19:08:53Z

The back-of-the-envelope goes:

Assume the same density. The mass goes as r^3. The gravity from an idealized point mass goes as r^-2. Then gravity goes as r^3/r^2 ~r.

Such a gravity estimate for these planets, assuming the same composition (wrong here) and disregarding compressibility (also terribly wrong if water worlds), is 40 – 70 % more.

It is interesting to note that cellular life doesn’t mind much for terrestrial range gravities. You can still have animals moving about in several g’s with the same type of muscles we have. With tension storage-release mechanisms like some insects and frogs, you can generate forces to move, with pauses and/or using parallel mechanisms, under 10′s, 100′s, if not 1000′s of g. (I’ll need to check that. But some accelerations created by their muscles are on that order.)

Likewise we can withstand 1000s of g (but not rapid shaking, like explosions) if liquid immersed, which is why a fetus can take a lot of accidental abuse.

And cells can withstand the pressure equivalent of 1000s of g in the deep ocean & crust.

It would be interesting to know, if Kepler-62e&f are water worlds, presumably with 100s of km of global oceans, how far down the cellular potential biosphere (habitable zone) goes disregarding pressure ices that will eventually “surface” (appear at depth). I don’t think anyone has touched that question yet.

Comment on Three new possibly habitable ‘super-Earth’ planets discovered by Tony Trenton

2013-04-23T11:11:13Z

Because the attractive force we call gravity is so essential to us.

What are the ‘G’ forces of these newly found planets ?