Comments on: Super-Earths: How Much Are They Like Earth?

By: Homer

Homer — Mon, 14 Jul 2008 11:37:59 +0000

@BOB

Bob, why do you insist in sayin this about uranus ?

Uranus is a beautiful place to be

thats why i fancy you babe

By: Homer

Homer — Mon, 14 Jul 2008 11:36:10 +0000

Uranus ?

By: Homer

Homer — Mon, 14 Jul 2008 11:35:27 +0000

yeh coz thats not my name

By: Homer

Homer — Mon, 14 Jul 2008 11:35:00 +0000

I think its a load of crap personaly

By: Shan Eris

Shan Eris — Mon, 14 Jul 2008 03:19:53 +0000

Re:"With that much more mass, would not the surface gravity be that much greater than Earth's?
All other things considered, no human could ever set foot on these worlds or risk being crushed to death!" Earth is the densest planet in our solar system, and Sol is relatively highly metalliferous. SuperEarths are probably less dense, and with a larger radius, so a tolerable 1.5 – 2.0 Gs is possible. As out techniques and equipment improves, the size of detectable extrasolar planets will decrease, but the unusual way our Earth/Moon formed means extremely few similar sized planets will be remotely Earthlike.

By: Bob

Bob — Wed, 18 Jun 2008 23:59:56 +0000

With that much more mass, would not the surface gravity be that much greater than Earth's?

All other things considered, no human could ever set foot on these worlds or risk being crushed to death!

By: Joe

Joe — Wed, 18 Jun 2008 15:26:13 +0000

I agree with Bill,

Imagine the seasons with a 20 days orbital period assuming its tilted.

Joe.

By: Jack

Jack — Wed, 18 Jun 2008 06:57:47 +0000

=Random thoughts of a Mad scientist-
It sounds like we are almost able to find Earth size planets. It is a shame they canceled the Terrestrial planet finder Projects, the longer we neglect this area of science the longer it is before I get off this rock.

Someone should Link the support voucher website….errr if their is one.

In all the history of man if I miss the finding of earth-like, life bearing planets by one generation I will be mad at god!!!

And I'm not sure that will go over well so get Finding!

By: Ronald Lynn Jackman

Ronald Lynn Jackman — Wed, 18 Jun 2008 04:48:26 +0000

Each type of star, its age, and the subcatagory of the star, determine its temperature. That determines its habitable zone. Red dwarfs have very narrow habitable zones close to them. That will help determine the type of planet it is as well as the materials. These are not by default extrasolar giant Mercuries. Titan, Triton, and Pluto are made of the same materials. We know there are dramatic differences between them. Red dwarfs might not produce sputtering, or the erosion of the atmospheres like a larger star. We might have a super Venus or two. Let's wait and see what the data says before we jump to conclusions.

By: Qev

Qev — Tue, 17 Jun 2008 22:40:12 +0000

@Andy:

The planetary systems we tend to find seem odd compared to our own, because they happen to be the sort that we find easiest to detect with our current methods, ie. big, heavy planets in close orbit around their star.

By: Matt

Matt — Tue, 17 Jun 2008 22:26:22 +0000

They should start working on the Terrestrial Planet Finder mission again… oh well, at least Darwin and Kepler will launch, I'm really looking forward to it.

@Gary: He was talking about Super-Earths that orbit farther away from the star than the one which we've found so far

By: trux

trux — Tue, 17 Jun 2008 22:12:29 +0000

If we are detecting a big number of planets close to their stars, it is just because they are much easier to detect than planets like in our system. It does not mean that they are more common. They may well be exceptions. We'll know once we refine the detection methods. And those planets on low orbits do not necessarily deny the planet formation theory – there are so many unknown factors, that we cannot know what got the planets so close. Collisions with extrasolar objects, or the gravitational effect of other stars passing close are only some of them.

By: Jon

Jon — Tue, 17 Jun 2008 21:29:00 +0000

Could principles of general relativity – namely frame dragging – cause larger gas giants to shrink in orbit over time?

By: Phil

Phil — Tue, 17 Jun 2008 21:14:59 +0000

Actually… I just looked up the gas giant I was thinking about (HD 209458b) and I think it was detected by Transit…. So it doesn't confirm this radial/wobble method like I thought… Does anyone know if this is solid science or is there still some debate about the radial/wobble technique?? (aside from the space mirror guy)

By: Frank Glover

Frank Glover — Tue, 17 Jun 2008 21:09:27 +0000

"It seems like planets this close to a star would be more ike giant Mercuries. I would think all traces of an atmoshere would ber stripped off, except for possible out gassing from the rocks or vapors of metals such a lead."

If so, then why does Venus, closer to the Sun, no appreciable magnetic field (to deflect charged solar particles) and about .78 Earth mass* have a denser atmosphere than Earth?

Those theories of why the atmospehre of Mars is so thin, don't seem to explain this.

* Hmm. If anything lived there, would they call Earth a 'super Venus?"

By: Phil

Phil — Tue, 17 Jun 2008 21:06:02 +0000

Surely they've confirmed that these wobbles are actually "wobbles" and they come from planets moving around the star?? I thought I had read (somewhere?) about astronomers detecting the atmosphere of one of these planets (a gas giant I think?)?

Either way it seems obvious to me there MUST be planets in all types of configurations, around all types of stars, and all over the universe!! I guess the question is how many?!!

By: Bill

Bill — Tue, 17 Jun 2008 20:31:37 +0000

It's curious that they are finding both rocky and jovian planets so close in. Either planetary formation theory is way wrong (truly, we knew it was, the disposition of 99% of the angular momentum of an accretion disk is still unknown), or the detections are false. Could we be simply detecting multiple harmonics on the surfaces of stars with the wobble method, rather than absolute motions of the whole star? Could the dip in the light curve seen by the transit method be akin to huge sunspots, or something like an orbiting coronal mass ejection, perhaps a darker distention from a round or elliptical star? I would feel much more comfortable with a dual transit/wobble confirmation, I don't think that has happened yet.

By: Gary

Gary — Tue, 17 Jun 2008 19:47:09 +0000

I doubt a planet with temperatures near 1000 C. would have oceans of any kind, let alone hot ice…even if they had a dark side because of no rotation.

More like Super Mercuries than super Earth's.

By: Nephish777

Nephish777 — Tue, 17 Jun 2008 18:38:51 +0000

Correction: … such as lead.

By: Nephish777

Nephish777 — Tue, 17 Jun 2008 18:38:04 +0000

It seems like planets this close to a star would be more ike giant Mercuries. I would think all traces of an atmoshere would ber stripped off, except for possible out gassing from the rocks or vapors of metals such a lead.

By: Al Hall

Al Hall — Tue, 17 Jun 2008 18:22:07 +0000

For the whole truth? And nothing but the truth, so help you [insert preference here]?

By: Al Hall

Al Hall — Tue, 17 Jun 2008 17:49:30 +0000

I'm not an expert on such things and haven't checked to see how old these systems are.. but perhaps some of them were like ours… and the last of the planets are being sucked in.. Just a thought.

By: Andy

Andy — Tue, 17 Jun 2008 17:43:08 +0000

How come all of these newly discovered systems are so different from ours? If systems form by essentially the same mechanism, shouldn't they be more similar? You know, small rocky worlds close in and gas giants farther out. I know some variation is to be expected but these really seem odd. It's not the sizes so much as the distances from their star. I mean their orbital velocities must certainly be approaching some physical limit. And could they really form at all where their orbits are now located? It's hard to imagine a large body coalescing from a cloud moving so fast.

By: Al Hall

Al Hall — Tue, 17 Jun 2008 17:03:12 +0000

I like the Space Mirror guy better… But he wants $10,000 for the truth about the universe..

By: Ronald Lynn Jackman

Ronald Lynn Jackman — Tue, 17 Jun 2008 16:54:59 +0000

Super-Earths would have more tectonic activity, hence making them more habitable. They could be on the outer edge of habitable zones and still have oasis of life with Yellowstone areas similar to Mid-Ocean Rift Valleys. On the bottom of their oceans would be hot ice because of the pressure of deeper oceans. Some of these may even be water worlds there–especially with Hot Jupiters, which theory says tend to help create them.