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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"....
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
Would we even be here?
Considering the climactic history of Earth, it's clear that even small perturbations in its orbit and small changes in the brightness of the Sun have large effects on the climate. In a binary star system, its not at all clear that any planetary climates would ever be steady enough to allow higher life forms to develop. Neither the orbit nor the energy received from the suns would likely be stable enough.
And the brethren went away edified.
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?
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!
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!"
Perhaps instead of thumping his Bible, he should have tried reading it before expressing his opinion. The book is silent on other planets and of course life on other planets, much less intelligent life on other planets.
Perhaps once could infer that there is no intelligent life on other planets based on theological complications with Jesus having to die for their sins too, but even that is speculation beyond what the book says.
The Bible has very little to say about scientific matters, despite what many theologians and Bible thumpers have decided up over the years. You would think people would have learned that making up stuff, claiming it was based on the Bible, and then getting trashed by the facts would have become unpopular since Galileo. BTW, the theoligians that disagreed with Galileo were following Aristotlean arguments not the Bible. Once again, the bible never says the earth was the center of the universe, etc. The Bible mentions the sun rising, etc. and people have inferred that the earth is at the center becuase of such language -- however, this is merely descriptive of the apparent sunrise, I can even read the sunrise & sunset times in the morning paper, and I am pretty sure that publisher know that earth orbits the sun, and the sun-rise is simply appearance, not a literal sun-rise.
Back to topic
Let's face it, the ability to directly image anything outside the solar system is pretty amazing. It was not very long ago that Betelgeuse was imaged as the first star (as a disk, not a point source).
There are some very interesting large-baseline telescopes that have been proposed that would theoretically allow imaging details of planets in other solar systems, alas they budget for such projects may be some time in coming.
It's still a long way to the nearest star. With current tech, would be be very lucky to get a large ship moving at 1 percent light speed, so we will have to settle for pictures for some time to come. Where is Zephran Cochran when you need him?
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.
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.
African Extraterrestrial Vertically Challanged Star
We do not live in the 21st century. We live in the 20 second century.
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)