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Fraser
2007-Jul-17, 05:20 PM
One of the big surprises the Universe had in store for extrasolar planet hunters is the number of enormous planets close into their parent stars - the hot Jupiters. ...

Read the full blog entry (http://www.universetoday.com/2007/07/17/large-outer-planets-are-rare/)

Leafguy
2007-Jul-17, 07:05 PM
How can they make this claim? Have they not looked at our own solar system which has 3 gas giants approximately 10 AU from the sun. Also the fact that they look at young stars for that study. I can't believe that simply because of the lack of depth to this experiment. They should be looking at more mature stars which would have more time for planets to develop. As for this experiment, conclusions should be drawn with a more complete sample and not just "young stars"

John Mendenhall
2007-Jul-17, 07:39 PM
How can they make this claim? Have they not looked at our own solar system which has 3 gas giants approximately 10 AU from the sun. Also the fact that they look at young stars for that study. I can't believe that simply because of the lack of depth to this experiment. They should be looking at more mature stars which would have more time for planets to develop. As for this experiment, conclusions should be drawn with a more complete sample and not just "young stars"

I'm inclined to agree with Leafguy, but this does constrain the case for young stars.

RUF
2007-Jul-18, 09:47 PM
They should be looking at more mature stars which would have more time for planets to develop.

I believe the planets in our solar system developed at about the same time as our sun. I don't see much difference between looking at younger stars or looking at older ones. An earlier article on UT about Iapetus said that it was "4.564 billion years old -- about the same age as the Earth" (and the sun, I believe).

I think that having giant planets in the outer reaches of the solar system is a fact that was overlooked in the Drake Equation. A gas giant in the outer reaches is needed to "vacuum up" all the debris in the solar system that could lead to an exinction event on a habitable inner planet.

This study has a bigger impact on the likelyhood of ET life.

Leafguy
2007-Jul-18, 09:51 PM
Ruf,
I agree that large planets are needed in the outer solar system to suck up debris. Much like the role Jupiter has played in the evolution of our own planet. Although, I don't think it is necessary for short term life to evolve, it is most certainly needed for any long term evolution to occur.

nauthiz
2007-Jul-18, 11:22 PM
They constrained the search to stars less than 250 million years old. What are the odds of a gas giant needing that much time to form?

markg85
2007-Jul-19, 03:28 PM
if they want to find jupiter like planets they will have to look in jupiter like orbit times.. this is a quote from [http://en.wikipedia.org/wiki/Jupiter]wiki - Jupiter[/url] : "it completes an orbit every 11.86 years" So i believe this research if they looked for about 12 years and than still don't find any at roughly the same size of our jupiter and about the same distant from the sun

Guess the researchers didn't had the time to wait for 1 years and than say thing like this.

I rarely have any critics at all on scientific publications but this one is just asking for critics. And it can even be that a jupiter sized planet just passed the sun that they where about to observe so they will definitely wait longer to see it again..

nauthiz
2007-Jul-19, 04:50 PM
Since the method they used appears to be to try and directly image the planet, they shouldn't have to wait for 12 years' worth of data. In essence, either the planet's there and visible, or it's not.

markg85
2007-Jul-19, 09:01 PM
but than again.. our moon is also always here.. and can we see it always? nope.. (same for everything in this solar system)
got the point? :p

m1omg
2007-Jul-20, 02:15 PM
Will that planet emit enough IR to be detectable.
Maybe it cooled faster than theory predicts and so even young giants are cool.

Disinfo Agent
2007-Jul-23, 07:42 PM
but than again.. our moon is also always here.. and can we see it always? nope.. (same for everything in this solar system)
got the point? :pThey have lots of stars they can look at. How high do you estimate the likelihood that their Jupiter-like gas giants all happen to be "hidden" at the same time?

DaveC426913
2007-Jul-24, 03:51 AM
They should be looking at more mature stars which would have more time for planets to develop.
I believe that current understanding of star system lifetimes show that the larger planets tend to spiral inwards - i.e. older systems would have more hot Jupiters. The younger systems will be the better bet for finding distant large planets.

Jerry
2007-Jul-29, 04:46 PM
How much is this conclusion driven by the assumption that the Jupiter-class planets in our solar system were part of a primal solar mass? The lack of observation of Jupiter-like systems evolving near younger stars may be hinting to us the theory about how the solar system evolved is incorrect.

nicholas25
2007-Jul-30, 07:07 AM
But weren't the large gas planets of the solar system the closer, inward planets when our Sun was young? I thought they migrated outward while Jupiter cleaned up everything as they went.