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13 Free-Floating Extrasolar Planets Discovered
Maestrogenic writes: "Researchers from the UK have discovered (using a new camera on the UK Infrared Telescope) 13 extrasolar planets, free-floating in the Orion Nebula. None of them are smaller than eight Jupiter masses though. This pretty much proves that vagabond planets are a common thing, and brings the total [number of] extrasolar planets discovered to above 40. Here's the official press release. " Note: the jpeg image linked to on this page is a beautiful shot, and downloads quite quickly.
Several orders of magnitude easier. The problem with the fusion of protonic hydrogen isn't getting the nuclei to overcoming coulombic repulsion. Helium-2 just isn't *stable*, so it immediatly disintergrates.
Occasionally though, He-2 will stabalise by emiting a positron and a neutrino so that the He-2 turns into deuterium.
This decay process takes place by the weak nuclear force, so it's very slow. Once we get past this point, the rest of the cycle to fuse hydrogen into helium is relatively easy.
What's the natural distribution of Deuterium to Hydrogen in the universe?
About 1 in 6000 atoms of hydrogen is deuterium. This appears to be fairly constant throughout the observable universe except in a few instances where some process will either increase/decrease it with respect to this value.
For example, some of the literature discusses some processes that will produce higher than expected values around some types of stellar phenomena ( type II nova and super-nova ), but no one has apparently been able to really confirm this at the moment.
How long would a brown dwarf burn for before fizzling and cooling off?
Sorry, no specific data on that one. The only tid-bit that I can add to this point is that it's also believed that Brown Dwarfs probably also fuse lithium. If that's the case, they will probably also use up the available helium-3 content as well. So overall, they will be using deuterium, helium-3, lithium-6 and lithium-7 for energy production until these are exhausted.
That might keep it going for a while, but only in the infra-red region. This really isn't my area of expertise, but I doubt that they would be emitting in the visible region of the spectrum ( but don't take my word for it ).
Now that you mention it, that sounds right. Somewhere, I have the anthology, I think.
R is for Rocket, perhaps?
Stock LyX does include the astronomical format file . . .
I think this was one of the earliest journal formats included, though I'm pretty sure it came after the AMS set.
Thousands of years, I'd expect, from when it was first detected, and when it got anywhere near our system.
It's not a foregone conclusion it would be captured--it could have a high enough velocity to prevent this, and just get its path bent.
*Please* do not create your own brown dwarf within the city limits. This activity should only be done in areas of the desert with no flamable plants.
The fire you could start in a crowded area would make the great fires in Chicago and San Francisco look like birthday candles . . .
The galaxy is a computer, and the universe a beowolf cluster . . .
The bad news is that our galaxy is running windows . . .
(now I remember)
The plan is simple. Planets are simply giant capacitors. IIRC, it's not very much, but 8 x Jupiter's mass should be a good start. Black Holes give you resistors (the internal resistance of a Black Hole is 33 ohms, according to Roger Penrose). You can turn Gravitational lenses into simple gates, allowing you to construct memory and processing elements.
Unfortunately, the 40 planets so far obtained will not be sufficient, and The Greak Whelk demands the turning over of Saturn and Outer Mongolia to complete his Great Plan.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
This is false. In fact, the proton-proton chain is the primary method of fusion powering our Sun. In the unstable nucleus formed by two fusing protons, one of them ends up emitting a positron, thus loosing its charge and becoming a neutron (it also emits a neutrino). The new deuterium nucleus then fuses with another proton, becoming 3He (He with only one neutron), and a gamma ray is emitted. Then two 3He nuclei fuse, forming ordinary He and emitting two protons.
--
"Convictions are more dangerous enemies of truth than lies."
If you're fond of astronomy pictures, you should know this wonderful site : Astronomy Picture Of the Day. Every day, it presents a picture related to astronomy, along with a small paragraph that gives some explanation. All previous pictures are still available. This site is a must see ! :-)
Calling these "planets" is a little misleading...these are stars that never got big enough. They are giant gas giants...
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There is also some controversy about when and where our gas giants formed -- there is mounting evidence that they formed much closer in, then drifted outwards to their current locations.
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"None are more hopelessly enslaved than those who falsely believe they are free." -- Goethe
The current (2000-04) issue of Scientific American has an interesting article on brown dwarfs. The author describes a technique for differentiating brown dwarfs from low-mass stars by looking for lithium in the spectra. Lithium is quickly burned up by fusion in normal stars.
Mea navis aericumbens anguillis abundat
Nice haiku. Sorry I can't respond in kind. :)
Conceivably yes, but the odds of two free-floating planets colliding is probably smaller than the odds of a couple hundred 747s colliding in midair and falling on your head. The combination of two big bodies (stars, planets) is called coalescence and has never been observed. Space is very big and planets are very small. Very nearly all of the mass concentration happens during the earliest stages of stellar birth.
I haven't been able to see the pics yet because the server is apparently already /.ed, but it is very unlikely the areas were removed. It's common in wide-field astronomical photos for the final image to not be rectangular. This is because the final image is composed of several smaller images, not because something was removed.
It automagically removes any sorts of defects that are common to CCD observations
You mean like images of little green men waving at the telescope like a bunch of morons standing outside a morning-show studio?
"If one is really a superior person, the fact is likely to leak out without too much assistance" -- John Andrew Holmes
Especially when you consider that Jupiter and Saturn are still cooling off (emitting more energy than they absorb from solar radiation) after however many billion years....
"If one is really a superior person, the fact is likely to leak out without too much assistance" -- John Andrew Holmes
You forgot c) when there's an enormous spectacle to be had. Landing on the moon didn't make any money and it didn't have any direct benefit for mankind (albeit plenty of indirect benefits), but like with the Mars rover, the American public sat up and took notice when NASA sent home some really pretty pictures. If NASA were to contrive some mission where they wanted to detect the effects of nuclear explosions in zero-g, as long as they took appropriate photos and silenced a few environmentalists, the masses would have their bread and circus and be happy about it. If you just think of how many millions of dollars are spent on fireworks displays annually....
"If one is really a superior person, the fact is likely to leak out without too much assistance" -- John Andrew Holmes
I assume you meant:
If 13 < Mass < 75 jupiters then Deuterium fusion: brown dwarf.
Intolerant people should be shot.
another NASA funding cut; when will people realize that knowledge cannot and shouldn't be measured in dollar signs?
Everything can be measured in dollar signs. You clearly think we need to spend more money on it, which means you're thinking of it in dollars. If you can't measure it in dollars, how do you determine how much money to spend on it?
So these planets have >8 Jupiter masses, but 13 Jupiter masses (the limit for a brown dwarf).
I think this simplifies to "really big gas ball". Or perhaps a "black dwarf".. Neat to see the distinction between star and planet blurred. It's all big spectrum...
Cool though. I didn't realize Brown Dwarfs actually underwent fusion for a short period. How much easier is it to fuse deuterium than raw hydrogen? What's the natural distribution of Deuterium to Hydrogen in the universe? (Same as in water on Earth?)
Red Dwarfs burn their hydrogen forever (well, about 15 billion years+, longer than the current age of the universe) but really dimly. How long would a brown dwarf burn for before fizzling and cooling off?
Check out Origins.
:)
and
Terrestrial Planet Finder
for more info on future directions in planet finding.
Just waiting for DS3 to get approved...
Well, if these brown dwarfs and megaplanets ARE produced in large numbers in our galaxies stellar nurseries, and then sent wandering, I'd guess a few might end up being captured -- say, somewhere in the vicinity of the Oort cloud of a certain M-type star. And since the megaplanets, at least, would rapidly cool, such a captured planet would be dark even in IR and hard to detect, not to mention having a highly eccentric and inclined orbit that would make it hard to locate. Just like the planets speculated about in this space.com article.
I'm looking for more info from the scientists quoted in the space.com articles (Matese and Murray) - I've read the papers before, and they're pretty interesting. They both present circumstantial evidence for dark Jupiter-mass-or-higher companions to the sun disturbing comets in the Oort cloud in a telltale pattern. Not quite the old comet-flinging Nemesis, but pretty close.
At the very least, this new information could prove that such dark objects exist, and that's half the battle, right?
Hmm, gravity too
weak for coalescence to
occur frequently?
Interesting. Thanks.
Runty planets--
even brown dwarfs have more mass!
(and get warm at night...)
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Time is Nature's way of keeping everything from happening at once... the bitch.
Hmmmm.... Yes... Yes I think I can see one of those huge gas giants now! MY GOD it's... It's tremendous! It's... oh... sorry... it's Marlin Brando.
Easy mistake.
Ceci n'est pas une sig.
You make some good points. Most of the people I know who call themselves Christians would agree with you.
Unfortunately, it's the self-serving evangelists and their brainless flocks who make their religion everyone else's business, and are most likely to riot at any evidence of extraterrestrial life. All of the intelligent, peaceful, thoughtful people in the world (Christians or not) will have much luck stopping an angry mob.
Furthermore, it seems like the religious hucksters almost always portray themselves as Christians, which (given the media attention they command) gives Christianity a bad name. In other words, when was the last time you turned on the TV and saw, "Phone the good Rabbi NOW with your pledge if you want to get into heaven!" It just doesn't happen for whatever reason. (I can think of several reasons why that might be the case, but that's too far afield for this thread)
Dislaimer: I am an avowed agnostic. Take the above as you see fit.
"People who do stupid things with hazardous materials often die." -- Jim Davidson on alt.folklore.urban
To answer questions re: looking for smaller planets -- NASA has plans to launch the Planet Finder Array -- a cluster of telescopes designed to do optical inferometry -- in about 2005. It will go into an orbit around the sun at roughly the same distance as Jupiter, and be capable of seeing Earth-sized planets out to about 50 light-years. Further, plans call for the ability to analyze the spectrum of the planet, which will allow for atmospheric analysis.
A recent issue of Discover magazine had a "field guide" to all the new extra-solar planets that we've found up to now. 47 Ursa Majoris has a Jupiter-sized planet that orbits its star at about the same distance Mars is from ours... Given that 47Uma is a little brighter and a little larger, this planet could very well have habitable moons, and is actually one of the targets for a new radio search, so the science already has applications.
As for the Hubble issue, I suspect it will be handled like Mir and kept aloft for at least five years beyond its expected life. There are plans for a "Hubble II" that uses a segmented mirror like the Keck. (And whomever asked about the X-Ray observatory: no, it cannot take over Hubble's duties -- it is without optical capabilities.)
blog |
We should all feel fortunate, or blessed, that our solar system and orbit turned out to be so beneficial for the sustainment of life. I can't even begin to calculate the odds against it. For the gas that formed our solar system mostly condenced into a large ball (the sun) and the rest formed into much smaller balls that had slightly eliptical orbits. One of which has a perigee far enough away from the sun so that all water is not a gas and a apogee close enough to keep it from being all ice. That does not seem too common, to me at least.
It seems that during the cold war, the US was a lot more motivated and interested in space development and exploration than after. I cringe each time I hear on the news another NASA funding cut; when will people realize that knowledge cannot and shouldn't be measured in dollar signs?
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JavaScript tutorials scripts
So are these 13 just wandering around muttering "I coulda been a star!"?
I see even classic Slashdot is now pretty much unusable on dial up anymore.
no planets have been found under 8 Jupiter masses. It may indicate that there is a limit to how small these free-floating planets can be
Or more likely, it may indicate that smaller planets have already cooled off to the point where they're not easily picked up by this survey. If the planets all formed about the same time (not unreasonable, if they're in the same cloud), smaller ones would be a lot cooler than larger ones for two reasons: they never got as hot in the first place (less infalling mass means less conversion of gravitational potential energy), and they cool off faster due to their greater surface area to volume ratio (square/cube law).
-- Alastair
...suppose one of them entered out system? i suppose it would be captured and begin orbiting our sun...
No, it would be very unlikely that our solar system could capture one of these, and absolutely the Sun couldn't do it alone (Jupiter or some other planet would have to help).
It's like the very long, elliptical orbit of comets. What keeps them from being captured into nice, circular orbits near the Sun? It has to do with momentum. Something falling into our solar system from a great distance builds up a lot of speed as the Sun's gravity tugs on it. By the time it reaches the inner solar system, it's got so much momentum that it swings around and shoots back out to where it came from.
Yes, a rogue planet falling into our solar system could do some damage. But that damage would be in the form of perturbing the orbits of some of the planets/moons/asteroids/comets in our solar family. The odds of collision are astoundingly small.
Lithium is also one of the (many) ways we know the Orion Nebula is young. The smallest of the Orion Nebula stars are too young to have started fusion, so many still have lithium. However, all of them more massive than brown dwarfs will eventually start fusion and the lithium will vanish (in a hundred million years or so).
What basically happens is that the data comes in off the telescope, and when ORAC-DR sees it, the data gets reduced. It automagically removes any sorts of defects that are common to CCD observations (flat-fields, bias levels, sky levels), and often produces publication-quality results. We were joking that astronomers wouldn't even have to write their papers. We'd just reduce the data, fill in some fields on a paper template, then ship the paper off to the appropriate journal.
Yes - you could make an Astronomer version of Lorem Ipsum tied into the LyX. I'm sure half the referees would pass it, and the other half would take it as a direct assault on their chosen field of expertize :-) Just joking folks!
Having done three nights of observing on UKIRT doing IR spectroscopy, having the automated reduction facility makes life a lot easier. Alas in our case it told our target object kept falling out of the slit, something later (i.e. after we left) found to be a problem with the telescope. Now fixed, but I don't think I'll get another chance at those observations. But such is life - and you really can't complain when you have to travel to Hawaii to do your observing :-)
And by the way, I'm glad to hear that Frossie's jeep is still in one piece - it was brand spanking new when I was there, and it was great fun bounding over the lava fields in it! Hiya to Tim too - long time no see - thanks for the accommodation!
Cheers,
Toby Haynes
Anything I post is strictly my own thoughts and doesn't necessarily have anything to do with the opinions of IBM.
here is the link to the story he mentioned. It really is a great article for us amature star gazers.
so we have these huge things floating around... suppose one of them entered out system? i suppose it would be captured and begin orbiting our sun also, but think of the damage it would do before settling down (if it ever would).
perhaps the next great "comet" movie should be about a free floating planet or star :)
.sigs are dumb!
Regarding these new discoveries, it will be important to make sure that the discovered objects are actually members of the Orion GMC, and not more distant objects. Spectroscopic measurements will help to do this. The fate of stars/brown dwarfs/giant planets is determined primarily by their mass:
If Mass > 75 jupiters then Hydrogen fusion: Star
If 13 > Mass > 75 jupiters then Deuterium fusion: brown dwarf.
If Mass less than 13 jupiters then no fusion: planet.
At least that's one way to define the terms. The very informative Sci. Am. article mentioned above can be found here If you want to Create your own brown dwarfs, and see what their spectra look like, try this site. -chris
I think that the press and the public will *never* be interested in science, unless: a) there is money to be made b) it has a direct benefit for mankind The problem with science and new discoveries lies in the fact that you never know beforehand what will come of it; you can compare this with research & development work in the IT world. At least 50 to 75% of the work will never see the daylight in terms of new software; but if you don't try, nothing ever changes. I think the only thing that can be done is to make ends meet, and try to work with the available budget (if any); I really wouldn't know how to get the public's attention. Maybe make space the new and exciting location for a new gameshow? ;)
I've seen really brief treatements in a couple of places in science fiction, but the most interesting one is the discussion with the chaplain on the chip in Pournelle & Niven's "The Mote in God's Eye."
In general, extraterrestrial life poses absolutely no threat to Christianity. The interesting questions come from whether other races our in need of redemption, like ours, or are in some other state.
ANd then if they are in need of redemption, would our Paschal Sacrifice, be sufficient, or would they need their own Christ?
Unfortunately, that discussion really didn't carry through the rest of the book.
Hmm, another interesting one is Lester Del Rey's . . . awe, nuts; I forget the title . . . Anyway, Christian Fantasy is fairly well represented, but this is the only novel of Christian Science Fiction I've ever seen. I recall another short story by someone travelling from world to world, getting closer and closer to Christ's life, death, and ressurection, but never quite making it. Anyway, in Del Rey's story, the first 50 pages are really slow, but the aliens find a dead and bombed out church, a crucifix, and Bible. They slowly translate it, and get caught up.
*argh* What's that title?
hawk
What basically happens is that the data comes in off the telescope, and when ORAC-DR sees it, the data gets reduced. It automagically removes any sorts of defects that are common to CCD observations (flat-fields, bias levels, sky levels), and often produces publication-quality results. We were joking that astronomers wouldn't even have to write their papers. We'd just reduce the data, fill in some fields on a paper template, then ship the paper off to the appropriate journal. *heh* When I left there was some talk of dedicating a Linux box to the data reduction (instead of the Solaris box they had then).
And it's a Perl-friendly environment at the Joint Astronomy Centre (the place that runs UKIRT in Hawaii). My supervisor (Frossie Economou) has written articles for The Perl Journal, she's got a stuffed penguin on her desk, and the license plate for her Jeep? "PERL5". Another software guy (Tim Jenness) has written stuff for Perldl and is altogether cool for Perl (and stereo equipment too...).
ORAC-DR information is found here. Props to Frossie, Tim, and Chad (who wrote the Apache modules that give the look-and-feel to the JAC webpages -- look for it on CPAN).
X-ray and gamma-ray emitting sources (high-energy sources) of radiation are usually signs of something very extremal going on: black holes, supernovas, neutron stars, pulsars. Now, a new family of such objects has been found -- the full article is in today's "Nature". What are they? Read the article, I'm not much of an astronomer :-)
Regards,
January
Vagabond planets--
if enough collide, do they
alight with fusion?