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Planet Discovered with a Massive Core
helioquake writes "A collaboration of astronomers discovers possible a 'Rossetta Stone' of planetary formation study, reported by San Francisco State Univerity and Subaru Observatory. This new planet, orbiting around G-star like our Sun (HD 149026), weighs roughly equal to that of Saturn, while its size is significantly smaller in diameter. Planetary modeling suggests that the core of the planet alone must have 70 times more mass than Earth, indicating the possible existence of a metallic solid core inside the planet. Just like the rocky planet discovered earlier, the finding of this dense-core planet may lead to better understading of the formation of rockey planets in the Universe."
YES! Got forth, and rape other planets!
You'd rather we stay here and rape this one? If there is no life on the planet, what is your objection to utilizing it?
-Charles
Learning HOW to think is more important than learning WHAT to think.
1) An object travelling in a circular (or eliptical) orbit requires a certain force toward the center of the focus of the orbit, called centripetal force. It is proportional to the product of the mass times the radius of the orbiting body, and inversely proportional to the square of the period of the orbit.
2) Two massive objects will assert an attractive gravitational force on each other, proportional to the product of their masses, and inversely proportional to the square of the distance between the objects.
All astonomers do is equate one force to another. Astronomers believe that they can calculate the mass of the star by observing the star's apparent brightness, and looking at the star's spectrum to figure out what kind of star it is. Unfortunately, the observed brightness of a star is a function of its distance from Earth, and this measurement has a large degree of error for most stars.
Next, astronomers look at how quickly the star "wobbles" due to the orbit of the planet. This gives a good measure of the period of the planet's rotation.
The final step is to figure out how far the planet is from the star. After entering in all the data, you are left with the mass of the planet being a function of its distance from the star. If you apply some trickery in the form of Kepler's Laws, you can see that the period and radius of an orbit are related.
And that's it! Put all the pieces of the puzzle together, and you have an equation for the mass of the planet. If you are lucky, then the plain of the orbit is end-on when observed from Earth--this allows you to see how much of the star's light is blocked from the eclipsing planet, giving you some measure of the planet's size and composition.
/*No comment*/ #No comment
My guess (I really have no idea, but it seems reasonable) would be that they can tell it's a gas giant, and may even be able to determine the type of gas by the reflected light. This means they can rule out the planet in its entirety being superdense. Then, based on the wobble of the star, they can determine the planet's mass. Since they already know the possible mass for a gas giant of its size, they know there is something within it that must have far greater gravitational attraction, and hence greater mass. Therefore, it must have a superdense core of some type.
Let me reiterate, I really have no idea what I'm talking about. Then again, that doesn't mean I'm not right ^_^.
Isn't that more like "planets capable of hosting the kind of life we're used to?"
If you have no interst in the universe outside your basement you probably won't get excited. However if you happen to be an astrophysicist or even have a remote interest in new discoveries then you might just find this interesting, because we've never seen anything like this before.
The planet in question posses the largest known core of any known extrosolar planet. So what? you say, well this just happens to be the first observational evidence supporting a planetary formation theory known as core accretion. So thanks to this observation confirming the theory, we now know that there should be a lot more of these planets. And as such a little bit more about the universe around us.
But of course because we cant get there tommorow this sort of work is a waste of time.... Tell you what, why don't you return to your cave and I'll send you an email when we've invented warp drive and found another planet. Then you can go live on it and the rest of us can waste out time with these boring discoveries.
Those bastard scientists - studying things that interest them. We should round them up and force to study more practical things... you know... your onto something there... but why stop at scientists? I say we round up all the programmers and make them do something useful like farming while we're at it. Why waste their time making video games, when they could be growing crops for hungry Africans?
There are legal restrictions based on the space treaty:h tm
http://www.oosa.unvienna.org/SpaceLaw/outersptxt.
But realistically, the only reason we don't exploit other planets or antarctica is that its too difficult compared to expoiting something on our own territory. Believe me, if they discover massive amounts of oil in antarctica, and an easy way to extract and ship it, we'll be doing it as fast as possible.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
Those non-practical forms of science eventually lead to the practical benefits you're seeking.
Science is inherently not practical. Most of the experiments that lead to the development of products we used today were not cost effective or useful. This is the core difference between a Scientist and an Engineer.
Scientists lay the ground work for the Engineers to "exploit" the behaviors the scientists find. That leads to products or developments on mass scale. If you blindly denounce the initial research as pointless though... guess what... it never gets accomplished, and the advancements/improvements to life/commercially viable products you're so found of never get made.
If man had always followed your advice, we'd still be waiting for a lightning storm to make fire!
While its all well and good to insist that corporations only spend money on things that make a profit - that has never been, and hopefully will never be, the mission of the US government.
Although, as someone (Martin Gardner?) once put it: If a stool weighs ten pounds, then the planet weighs ten pounds relative to the stool. (Turn the stool upside down!)
Life is order.... lots of it.
Heat is, broadly speaking, disorder.
While I, and a lot of scientists, would hate to go on record as saying something is flat out impossible, when your planet's heat gets high enough that all complex molecules are impossible, and any putative other type of order that might lead to life is jittered into unrecognizability in mere fractions of a second by heat, it's hard to imagine enough order on the right scale forming.
So, even though I can't say 100% it's impossible, I'm pretty comfortable with the idea that life isn't possible on these planets. Real life isn't Star Trek.
(After all, I'm not even willing to say 100% that I'm not a brain in a vat. "Impossibility" is really inherently a relative term, if you want to be rational about it.)