Solar system may be one of a kind

Reuters ^ | Thursday, August 5, 2004

[presidio9]

Our solar system may be unique after all, despite the discovery of at least 120 other systems with planets, astronomers said on Wednesday.

All the other solar systems that have been found have big, gassy planets circling too close to their stars to allow them to be anything like Earth or its fellow planets, the British and U.S.-based researchers said.

If that is the case, Earth-like planets will be very rare, the astronomers write in the latest issue of the Monthly Notices of the Royal Astronomical Society.

"Maybe these other extrasolar systems ... contain only the giant planets," said Mario Livio of the Space Telescope Science Institute in Baltimore.

Livio and colleagues took a close look at what is known about the other planetary systems that have been discovered.

[Hermann the Cherusker]

Juptier's moons are much smaller than Earth. The largest ones have a diameter around 1/8 that of Earth, meaning they are 1/512 the size of Earth.

[jpsb]

Yes but one can determine the distance the gas giants orbit theirs suns. Seems there is a narrow range in orbits that would permit liquid water and if a giant gas planet is in or near that range then an earth like planet could not be there too. And that assumes circular orbits, if any gas giant has an elliptical orbit then once again an earth like planet can not exist.

[jpsb]

Th universe is not infinite, it is finite but boundless.

[wireman]

Solar system may be one of a kind...

Then again, it may not.

[martin gibson]

...what are the odds that ANOTHER Democrat Party could exist somewheres else?

That's not a Democrat, that's Uranus...

[js1138]

ping

[Logic n' Reason]

". . .may be unique after all,. . .".

Then again...may be not!

[presidio9]

Since over 250 people have decided to read this thread in the half hour since you posted it and you are the only one who made a smart-ass remark, I guess you are in the minority.

Ususally people wait at least a week after signing up before instructing others on what is and what is not newsworthy.

But, then, I guess you are trying to get in as many lame one-liners as possible, since you won't be sticking around for too long.

[Arthalion]

Bingo, the original article is bunk. We've only discovered "odd" solar systems to date because our current methods for detecting extrasolar planets are limited to detecting stellar "wobbles" or observing shifts in a stars brightness. Using these methods, it would be impossible for an observer around a nearby star like Barnard's to detect the presence of our own solar system, and yet nobody questions its existence. Why isn't it detectable? Because Jupiter is too small, its orbit is too regular, and its too far out to create the kinds of wobbles we're looking for. I believe I read somewhere that Jupiter shifts the orbit of our sun by about 30 feet, while the Earth shifts it by mere inches. These gas super-giants orbiting in wild elliptical orbits, in contrast, shift the orbits of their host stars by hundreds, thousands, or even tens of thousands of miles, which our sensitive telescopes can detect.

Detecting planets using variations in brightness is even more troublesome because it requires that the planets be A) massive enough to reflect enough light change the brightness of the host system (Jupiter may be big enough to do this...if it were closer in). Or B) That the solar system face us "edge-on" so the orbiting planets partially eclipse the central star (an extremely unlikely alignment).

As telescopes get better and we gain the ability to actually see these planets rather than inferring their presence through their effect on their solar system, we will begin to find more "normal" terrestrial planetary systems. We'll never find another Earth, of course, because we've evolved as an isolated planetary system for billions of years and our biosphere is our own, but I have no doubt that we will find Earth-like planets, possibly even with life of their own (I'm not saying intelligent life, just life).

[drhogan]

one theory is that the big, gassy planets like Jupiter are made up of lots of democrats.

[jpsb]

Yall none science types are starting to piss me off with you “wobble” arguments. First the article is not about our ability to detect small earth like planets. Everyone knows we can’t do that yet. The article is about the MODEL used to explain how solar systems form. It seems that the MODEL might be incorrect, and if the MODEL is incorrect THEN maybe solar system like ours are rarer then we used to think.

Jezzz.

[PatrickHenry]

Thanks for the ping. We had a very recent thread on this: Earth-like planets may be more rare than thought.

[Publius6961]

There is speculation, and then there is dumb speculation.
I am sure that a flea on an elephant thinks there is only one elephant in the universe, too.

[TomServo]

Sping!

[talleyman]

I would have thought space itself would be littered with democrats.

Kerry's wife - the Extra-Terezial - proves there's 'Rats in outer space.

[SerialRants]

Hmm. 250 people read it. Any idea how many people took a glance at it and thought, "lame" and bypassed it? Of course not. So considering the thousands of visitors that carouse these forums and the only 250 that actually read the post in that half hour, perhaps I am not in the minority...

As for the 'waiting a week before signing up', I've been doing the FREE REPUBLIC thing for many years now. Not my fault sensitive people like you read them and cry and try and get me blocked.

Then again, a sense of humor probably wouldn't appeal to such an 'intellectual' like you. He can post this stuff all he wants, I could care less. In fact, I urge more posts like this. Please post more stuff from newscientist.com and slashdot.org. Perhaps I'll start a post of my own on 'UNIX Firewalls' and 'Scientists isolating the genome responsible for lamers like you'. Get a life.

[Noachian]

What has been seen up to now does not bode well for the main purpose of seeking other planets -- finding life outside our solar system

If that's true then why spend billions of dollars trying to find life on other planets?

Why not spend those billions exploring and colonizing our own system and beyond? That's a surer way of finding alien life then sending out expensive probes that almost always fail.

[Izzy Dunne]

And Livio said as much later on in the article:

But he said it is hard to tell as planets outside this solar system can only be detected through indirect observation and these methods are not able to detect smaller planets like Earth.

[Arthalion]

Erm, read the article again. It is being proposed that the model might be incorrect because we haven't found any stable terrestrial planetary systems yet. My point was that we haven't found any stable terrestrial planetary systems because our detection methodology favors the location of elliptical gas giants. They are basing their suppositions about the formation of planetary systems on flawed and heavily biased data.

Nothing found to date invalidates the standard model for planetary formation, or even throws it into any kind of serious question.

[hershey]

Aha! Besides which, we theorize that there are what, eleven parallel universes? In at least one of these, I am happy, rich and successful beyond my wildest dreams. Smarter, too.