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First Image Of Planet-Like Body Orbiting A Star
deglr6328 writes "The Gemini North Telescope has, for the first time, directly imaged a planet like body orbiting a star. The object is a brown dwarf, 55 to 78 times the mass of planet Jupiter and 14 AU distant from its parent star 15 Sge. It was imaged using adaptive optics(see also here) that correct for the blurring effect of the atmosphere using deformable mirrors. Cool!"
Is that a Starbuck's I can see on the high-res JPEG?
while you're there
http://astra.hi.gemini.edu/gallery/science/
"Everyone is entitled to their own opinion, but not their own facts."
I say we name it "Rosie" or "Oprah"....
Well, they say that some 75% of the internet's bandwidth revolves around heavenly bodies.
Even though the "photograph" is of just two fuzzy blobs it's cool nonetheless, especially that the first thing photographed should be celestial object that we don't have in our solar system that also happens to simultaneously prove that there have to be numerous ways that solar systems are "born" in the wake of a star's formation.
One wonders if the cosmic soup had simmered a little more or a little less if Jupiter wouldn't be a binary star. How would it affect sleep patterns? What the hell would our watches look like?
Who did what now?
Are they absolutely sure someone didn't sneeze on the lens?
Nick
a Brown Dwarf is said to be Classified Less massive than stars but more massive than planets,
brown dwarfs. so.. at 78 times the size of jupiter how massive is massive? and how massive is it not massive compared to a star?
The More Knowledge you have the Luckier you Get- J.R. Ewing
"The great thing about multitasking is that several things can go wrong at once." -me
This is the first planet seen outside the solar system, okay? Previously we'd been able to detect planets through other means (ie a larger planet's gravitational influence on its star) but now it seems we've been able to get an actual visual of one. That's why this is news.
________
"And if the fool, or the pig, are of a different opinion...." -- J.S. Mill
I had a high school physics teacher that was a bit of a bible thumper (no offense to any thumpers out there) who insisted that we would /never/ find planets (or planet like objects)in other solar systems. It was impossible, because . Something about proof denying faith, and without faith God being nothing ... oh wait -- that was someone else.
...
I'd love to talk with him now
Like the article says, brown dwarves cannot be considered stars since they do not generate energy from a thermonuclear reaction. Having said that though, they DO give off more energy than they receive from outside sources, much like Jupiter does but on a far larger scale. A good primer site for brown dwarves can be found here .
Lastly, it is important to not confuse brown dwarves (almost stars) with white dwarves (dying stars).
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I didn't want to leave this space blank.
What ever happene dto Gliese 229?
That was imaged back quite a while ago by a caltech team.
I found papers about it at Jean Schnieder's webpage, but not a listing...
Do you know why the road less traveled by is littered with the bones of the unwary?
Until we see it moving around that other star in an ellipse, it's just some bright pixels next to some other bright pixels. Hopefully, in a few months, we'll get to see some relative motion from it.
By the way, while you are on your campaign to protect innocent lives, you better take on drunk drivers, pollution, serial killers, cigarettes (maybe not innocent, but still..) AIDs victims (especially in '3rd world countries'), etc. You better get moving.
What?
I can't believe that scientists are still using terms like "brown dwarf". Am I the only one that forsees a protest by african american and vertically-challenged groups? :)
I still have a high-school science book that states "a star will appear as a single point of light even in the largest telescopes"
Now we can see surface features on stars and even objects orbiting them. Pretty cool. Imagine what an orbiting interferometer will do!
so they drew it in, right? i can do that too! look, planets!
It is not quite that bad. This link here is really nice. I'm putting in a plug for my old alma-mater (go slugs.)
Yeah, the pictures are pretty (awesome, if real) but I'm going to wait for pictures from the Hubble (which had better be forthcoming!) before I'm totally persuaded.
That said - 58 light years? That's a long trip, but totally possible.
The good and new comes from no quarter where it is looked for, and is always something different from what is expected.
Someone needs to mod the above up; it's important. I would have rephrased the post to reflect that this was NOT the first image of a brown dwarf orbiting a star if I knew about it before I submitted the comment.
On closer examination, the Gemini North press release does not claim to be the first to image a brown dwarf; from the site:"The faint companion is separated from its parent star by less than the distance between the Sun and the planet Uranus and is the smallest separation brown dwarf companion seen with direct imaging". It is only the CNN story that incorrectly claims this.....Hmmmm perhaps a notification is in order.
- "Hear that?! The percolations are imminent! Cease your ingress!"
If Jupiter had somehow been lit (by being hit by an object the size of uranus, say - I've been told that would have done it), it would have burned out in the deep, deep precambrian (billions of years ago). It doesn't have five billion years of fuel. While burning in the early stages of earthly development, it would have been about as bright as the moon (of course, the sun at that time was bluer and overall dimmer). Butterfly flaps it's wings in China, I know, but I don't think it would have been enough of a change in the overall radiation level on earth that whatever conditions allowed life to rise on earth wouldn't have been in effect. Given those conditions, you ask - is life likely to arise, or is it a rare event even in the conditions that favor it (over the course of billions of years,) such that a tiny change in conditions could have prevented that one spark of life from occuring? As a molecular biologist with interests in the field of molecular evolution and structural biology, I'm going to say - no, given that conditions that favor the appearance of life (as a chemical phenomenon) it's going to happen.
If Jupiter were more massive - simply igniting it without changing it's mass wouldn't cause it to exert more gravity - well, yeah, all bets are off, since that would imply very different things about the environment under which the entire solar system formed. Although, it just occured to me, Jupiter's core is still undergoing nuclear reactions (so is the earth's core) just not on a stellar scale. I don't see how we'd know if those reactions had been much faster/brighter three billion years ago. We'd have to guess from the amount of heavy hydrogen present in the Jovian atmosphere, and I don't think our measurements (radio spectroscopy? something about Jupiter's magnetic properties?)are precise enough to figure that out.
The good and new comes from no quarter where it is looked for, and is always something different from what is expected.
...Won't someone go to the effort of making a pun involving the words "brown dwarf" and "uranus"!
I am almost certain it can be done. Someone out there must have the technology.
:)
As you can read, as far as 1995, the Hubble Space Telescope imaged a brown dwarf orbiting a brown dwarf on Gliese 229B. Indeed, some of the US media call it "the first discovered brown-dwarf" although the discoverer was Rafael Rebolo et al at the Instituto de Astrofísica de Canarias (he and his colleagues proposed the "Lithium test" method to actually detect this substellar objetcts). You can read a short report about brown dwarf findings at American Scientist.
Víctor R. Ruiz
rvr(at)blogalia.com
It's not a matter of whether or not Jupiter gets "lit". The sun was never "lit" as you speak of it. The sun is massive enough that the gravity well in the center is massive enough so that the nuclei of hydrogen particles collapse into helium (and these can collapse into heavier elements; our sun reaches it's limit around Oxygen. heavier elements are made in more massive stars). This collapse of nuclei into heavier nuclei is called fusion (gives off lotsa energy). Now for Jupiter to become a star it would have to be around the order of 100 times more massive than it is now (though that's still much less massive than the sun). With that much more mass it would definately affect the orbits (and possibly even the accretion, as there would have been an planet where the asteroid belt is were it not for Jupiter's current mass) of all the planets.
Also, the nuclear reactions going on inside the Earth and Jupiter's cores are fission based (decay of unstable elements). This is completely different from what's happening in the Sun so comparing this to what was happening in the early stages of the solar system is pointless.
adaptive optics have the ablity to create images at the same resolution of the Huble space telescope. I wonder what this means for it's future. Seems kinda pointless now.
( I submitted an artical about it to slashdot a month or so ago, but it was rejected..)
autopr0n is like, down and stuff.
. Now for Jupiter to become a star it would have to be around the order of 100 times more massive than it is now (though that's still much less massive than the sun).
Well, that may or may not be true. The question is - can you get Jupiter's core under enough pressure to undergo fusion? The fact that it is undergoing fission now is relevant because fission of the sort occuring in Jove's core also requires considerable (although lesser) density/pressure. The heavy elements may also provide a source of high energy alpha particles to help fusion get started (like in a modern H bomb which uses fissioning technitium as a trigger.)
So, PV = nRT, right? Well, if Jupiter were hit by a uranus-sized object moving perpendicular to the orbital plane -
1) It would put off huge amounts of heat (q = delta T / S) which might increase the pressure in Jupiter's core enough to ignite it.
2) The actual impact would involve a lot of force, as well - the whole planet would deform like a ball bouncing off the wall of a squash court. This would constrict the volume available to the core (lowering V, raising P) as well as causing huge differentials in density (raising n locally) as the planet bounced back into shape.
I'm not sure if that would be enough to do it, but once Jupiter is "lit", the fusion processes in it's core WOULD put off enough heat to be self-sustaining.
Also, the nuclear reactions going on inside the Earth and Jupiter's cores are fission based (decay of unstable elements). This is completely different from what's happening in the Sun so comparing this to what was happening in the early stages of the solar system is pointless.
Actually, fusion is decay of unstable elements as well - heavy hydrogen nuclei are hit by other heavy hydrogen nuclei and "decay" into helium nuclei. The fission at earth and jupiter's cores is NOT spontaneous decay like you see in a sample of carbon 14 that is left to sit (at least not mostly). It's collision-mediated decay, a slow form of chain reaction like you see in a detonating U235 bomb. That is to say, like nuclear fusion, the fission that occurs in the earth's core is collision mediated.
Thank you for pointing that out though, since I agree that my previous post certainly didn't draw a distinction between the two.
The good and new comes from no quarter where it is looked for, and is always something different from what is expected.
They're admitting that it's all done with mirrors?
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PGP Key ID 0xCB8FF658
As for the HST's future, it's scheduled for EOL at the end of the decade. Check out NASA's Next Generation Space Telescope page for its successor.
The object is a planet, 1/55 to 1/78 the mass of a brown dwarf. View the photo.
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- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
If Jupiter had somehow been lit ... it would have burned out in the deep, deep precambrian (billions of years ago). It doesn't have five billion years of fuel.
No. It would outlive the Sun. The larger a star is the greater the internal pressure, and the faster it burns fuel.
Small stars are long lived, large stars burn out fast.
- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
the abstract for the technical article is already on the preprint servers. it's much better than the cnn article, for the technically trained. (the complete article was temporarily withdrawn, but they tell you how to get it.) see http://xxx.lanl.gov/abs/astro-ph/0112407
African Extraterrestrial Vertically Challanged Star
We do not live in the 21st century. We live in the 20 second century.
Usually, dimmer stars burn much longer than brighter stars, so unless the planet-hit/lit-by-some-huge-asteroid is some strange exception, it should still burn today and should all in all burn much longer than the sun.
The Law of Hydrostatic Equilibrium: Within every layer [of a star], the outward force of pressure equals the inward force of gravity.
Stars must have M 0.08 Msun to fuse hydrogen.
There exists a high-mass cutoff because very high mass stars cannot attain hydrostatic equilibrium. Very high mass stars produce enormous numbers of high-energy photons (L and T are both large). Photons exert pressure on gas (an effect called radiation pressure.) Ordinarily, the effects of radiation pressure are small, but for stars with M > 60 Msun, models indicate the radiation pressure is large enough to blow the star apart.
When a star exhausts the supply of H (hydrogen) in its core, it becomes a giant or supergiant, depending on its mass.
Once a star has used up all the H in its core, fusion of H into He (helium) stops. The core starts to contract just as it contracted as a protostar before H fusion began. As the core contracts, it releases energy. This energy heats up the layer immediately above the contracting He core. The layer immediately above the core becomes hot enough to initiate the fusion of hydrogen into helium.
The star now has three main layers:
(1) Helium core (inner layer): Releases energy as it shrinks in radius.
(2) Fusion shell: Releases energy as it fuses hydrogen into helium.
(3) Hydrogen envelope (outer layer): Absorbs energy, and swells greatly in size.
These swollen stars are now giants (if M 8 Msun).
Supergiants and giants with M > 0.4 Msun become hot enough to fuse He into C by the "triple alpha process", making primarily C (carbon), sometimes overshooting and making O (oxygen), and making Be (beryllium) as an intermediary product (and lots of gamma rays, too).
Once a giant or supergiant begins to fuse He in its core, it has four main layers.
Supergiants and giants with M > 3 Msun become hot enough to fuse C into heavier elements.
There is a limit to fusion: Iron (Fe).
The stages in the life of a 25 Msun star:
Hydrogen fusion lasts 7 million years
Helium fusion lasts 500,000 years
Carbon fusion lasts 600 years
Oxygen fusion lasts 6 months
Silicon fusion lasts 1 day
The star's core is now solid iron: end of the line as far as fusion is concerned.
Two choices:
(1) The star finds an alternative pressure source to maintain hydrostatic equilibrium which doesn't rely on the random thermal motions of atoms and ions; or
(2) The star collapses giving you:
a) black hole
or
b) nova/supernova
All clear now?
woof.
citations/references:8 starrfield.html
4 /n otes16.html
e r2 1.html
http://www.sciam.com/specialissues/0398cosmos/039
www-astronomy.mps.ohio-state.edu/~ryden/ast162_
cse.psc.sc.edu/hses/StarEvol/pages/reds.htm
blueox.uoregon.edu/~jimbrau/astr122/Notes/Chapt
www.imsa.edu/edu/astrophys/studentwork/inquiry/ (not as good)
More importantly: a bitch-slap from a passing asteroid will not "ignite" a big-ass ball of H & He. This is astrophysics, here; we're talking about 20000000000000000000000000000000kg of hydrogen, not Strike-Anywhere White-Tip kitchen matches!
Jupiter is about 1/80 the mass needed for ignition, which occurs due to heating from internal gravitational collapse.
woof.
"Ignite Jupiter", indeed! Then again, I once thought you might be able to "execute" a star simply by hitting it with a chunk of iron (see my other post on this thread.)
> The sun is massive enough that the gravity well
> in the center is massive enough so that the
> nuclei of hydrogen particles collapse into
> helium
The gravity of the sun isn't great enough to directly override the nuclear forces and cause fusion to occur. The weight of all the sun's material pressing inward because of that gravity, however, is great enough to cause fusion.
"All representatives are busy. The estimated hold time is one..hundred..sixty..four..minutes." Detroit Edison, 02/01/02
An actual image of a planet-like body orbiting a star? No way!
The mass is deceptive.
The body is closer to the size of the Sun than Jupiter.
Still brown dwarves are important to study and may be very common in the universe.
Thus, he also proved that science did not end with the Bible, as many people believed.
What?
Except that it's bigger than a planet, and it's the second brown dwarf we've got an actual visual of. (Search upwards for the main discussion of Gliese 229B -- there is a "first" in a very narrow sense, but it's not the first visual.)