'Hundreds of worlds' in Milky Way (BBC)

[eppur_se_muova]

By Helen Briggs
Science reporter, BBC News, Boston

Rocky planets, possibly with conditions suitable for life, may be more common than previously thought in our galaxy, a study has found.

New evidence suggests more than half the Sun-like stars in the Milky Way could have similar planetary systems.

There may also be hundreds of undiscovered worlds in outer parts of our Solar System, astronomers believe.

Future studies of such worlds will radically alter our understanding of how planets are formed, they say.

New findings about planets were presented at the American Association for the Advancement of Science (AAAS) in Boston.
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more: http://news.bbc.co.uk/2/hi/science/nature/7249884.stm

[JeffR]

1. I only hope there isn't a species like ours on each of those worlds

fucking things up at a furious pace.

[Adsos Letter]

2. Hey, JeffR!

that's one of the reasons I'm no big fan of space programs designed to someday bring us into contact with other life forms... we can't get our own act together and we are going to "introduce" ourselves to some other "civilization?"

:scared:

[JeffR]

3. Nice to see you! You're right, we're toxic. Clever enough, though.

It's a marvel to me that we can simultaneously be sophisticated and diligent enough to scour the near galaxy for information about the universe, yet so stupid that we have yet to learn not to foul our own nest. Now that our nest is the entire planet, this takes on a queasy urgency.

[Adsos Letter]

4. "Now that our nest is the entire planet, this takes on a queasy urgency."

Indeed it does, my friend. And, on another note, consider the Native Americans...look how well "getting discovered" worked for them...

[JeffR]

5. Yes!

Reading Jared Diamond's "Guns, Germs and Steel" last year got me thinking about that. Grim.

[Adsos Letter]

6. we were just discussing Diamond's work in my Historical Methods seminar last week...

lots to chew on in that work. A less skilled author couldn't have pulled it off, I don't think. Good reading!

[JeffR]

7. and sobering

It was a great achievement, and if it made one more person think about the real ramifications of what we do, it was a boon to humanity.

[Peace Patriot]

8. "...there are hundreds if not thousands of planets in our Solar System" !!??

I found this statement, further down in the article, to be even more startling than that there may be planetary systems similar to our own around "half the Sun-like stars in the Milky Way." I didn't know that there could be any objects as large as the earth in our own solar system that are undiscovered. We can detect quasars at the far, far edges of the known universe--objects whose light reaching us is almost as old as the universe--and we may have missed earth-sized objects in our own backyard?!

-----

Some astronomers believe there may be hundreds of small rocky bodies in the outer edges of our own Solar System, and perhaps even a handful of frozen Earth-sized worlds.

Speaking at the AAAS, Nasa's Alan Stern said he believes we have found only the tip of the iceberg in terms of planets within our own Solar System.

More than a thousand objects had already been discovered in the Kuiper belt alone, he said, many rivalling the planet Pluto in size.

"Our old view, that the Solar System had nine planets will be supplanted by a view that there are hundreds if not thousands of planets in our Solar System," he told BBC News.

He believes many of these planets will be icy, some will be rocky, and there may even be objects the same mass as Earth.

"It could be that there are objects of Earth mass in the oort cloud (a cloud surrounding our planetary system) but they would be frozen at these distances," Mr Stern added.

"They would look like a frozen Earth." (MORE)

http://news.bbc.co.uk/2/hi/science/nature/7249884.stm

[Phoonzang]

9. I'm guessing these planets are too

far out to reflect the light of the sun and their gravity has no effect on the visible bodies in our solar system (once again because these planets are so far out). I figured that there were thousands of other planetoids out there, but never thought that there'd be some the size mass as Earth.

[eppur_se_muova]

10. A great setting for hard-core SF!

"We have our own planet -- and you can't find it!"

[Xithras]

11. And they would orbit so slowly that detecting them would be nearly impossible.

It's certainly possible that there are Earth sized objects further out in our solar system, but I don't think it's probable. The Oort cloud is large, but it's also very thin and dispersed. If you had a spacecraft and could fly out there, you wouldn't see a thing simply because the density of material is so low. It is low enough to make the accretion of enough matter to form an Earth sized planet unlikely. I don't doubt there are several more Pluto sized worlds out there, but anything larger requires some long odds.