Extra-solar Planet Imaged

Awesome! by cephyn · 2004-09-10 04:43 · Score: 1

Fantastic and cool. The only question I have is...where the hell is it? no where in the article could I find where to point a telescope to see it. I hope, for scientific verification, other astronomers have access to that information somewhere.

What's a little disappointing is that this planet is orbiting a brown dwarf, which isn't really a star...but its a start!

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Moo.

Re:Awesome! by sartin · 2004-09-10 04:54 · Score: 5, Informative

They did identify it as 2M1207 at 230 light years. A quick google suggests this set of coordinates from some Prospero observations in February, coordinates reproduced here (the original file has observation configuration as well):

# Prospero Observation Template File
# Created: 2004 Feb 12 [9:36:32] by saveobs.pl Version 2.2
# For: John Gizis
#
PROJECT=UDEL-04A-0005
IMGTYPE=OBJECT
OBJECT=2M1207
RA=12 07 33.4
DEC=-39 32 54
EQUINOX=2000.0
MODE=DUAL
Re:Awesome! by Anonymous Coward · 2004-09-10 04:57 · Score: 1, Interesting

Fantastic and cool. The only question I have is...where the hell is it? no where in the article could I find where to point a telescope to see it. I hope, for scientific verification, other astronomers have access to that information somewhere.

I am not an astronomer, but I don't know how visible a brown dwarf at 230 light-years, much less the possible planet, would be to most backyard telescopes. However, if you are a serious amatuer, with serious equipment, I'm there are star charts that list the location of 2M1207.

What's a little disappointing is that this planet is orbiting a brown dwarf, which isn't really a star...but its a start!

That has been a debated point for a while, and I guess it will continue to be until someone either vists one or sends a probe to vist one.
Re:Awesome! by cephyn · 2004-09-10 05:10 · Score: 1

well i was a little vague...i know its not visible to the backyard telescope, but id like to know where in the sky it is, just so i could point to it and say "yeah, over there" -- the star chart info is great, but im an astronomy chart n00b. now if someone said "dead center in the pan of the big dipper" or "a few inches to the left of betelgeuse", thats enough for me. 8)

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Moo.
Re:Awesome! by sartin · 2004-09-10 05:47 · Score: 3, Informative

RA 12, DEC -39 puts it in Hyrda, which according to 5 seconds of looking in "Distant Suns" trial version on my work Windows box, is seriously blocked by the Sun these days. It's about 45 degrees south of Leo, whenever it becomes visible.
Re:Awesome! by Shigeru · 2004-09-10 10:05 · Score: 5, Informative

The preprint of the paper lists the parent brown dwarf as 2MASS J12073346-3932539 , which is indeed at the above coordinates. The candidate planet (much in the same way Ralph Nader is the candidate president, but there's my bias showing) will be 0.46 arcseconds south and 0.63 arcseconds east.

In case I didn't discourage any amateur astronomers thus far, here's some more: That's a separation of 0.77 arcseconds, when the seeing at most sites is of order 1 arcsecond. The companion is 100 times brighter than the parent brown dwarf in the K band. The parent brown dwarf has a K of about 12, and for an M8 spectral type, that's a V-magnitude of about 19 or 20. For those of you scoring at home, the parent brown dwarf is one million times fainter than anything you can see with the human eye.

The companion is an even redder object, so the colors will be much, much worse at V (there's a reason we try to detect these in the infrared). With a state-of-the-art AO system (look what we did with the same system earlier this year imaging the surface of Titan) on an 8 meter telescope with excellent infrared detectors, the companion lies one magnitude above the detection limit on their sensitivity/separation curves.

Sorry to depress people looking forward to pointing your telescope at this system tonight, but if it makes you feel better, it's probably not a planet.

I just checked that RA, by the way. It's behind the sun right now. You'll have to wait until January to observe it. Or to point your telescope there and not observe it, as the case may be.
Re:Awesome! by JQuick · 2004-09-10 12:49 · Score: 4, Interesting

>What's a little disappointing is that this planet is orbiting a brown dwarf, which isn't really a star

Arguing that it is not a type of star seems questionable. There is a grey area between giant planetary objects and tiny stellar objects. Brown dwarves share properties with both at various times in their evolution.

A Brown dwarf masses between 1 and 8 percent of our suns mass (which is a yellow dwarf). This mass is too small for gravity to produce high enough temperature and pressure in the core to sustain the fusion of hydrogen nuclei into helium 4. However this does not mean that fusion cannot occur. It also does not mean that the surface temperature of the body, or the luminosity of the body are not star-like at some point.

Gravitational contraction alone raises the temperature of the gas considerably. Though the surface temperature of a typical brown dwarf may be as low as 1000K, early in their career the heat generated by their gravitational collapse be be high enough to shine red for a short time. Larger brown dwarves may also have pressures and temperatures at the core sufficient for deuterium and tritium based fusion reactions. The resulting release of energy is futile as it is far too small to even temporarily balance or reverse the gravitationally induced contraction. They couldn't make a go of fusion on the professional circuit, but fusion is fusion. If star-hood is a nuclear club, their amateur standing should count .

Yes, they are dim and cool. They can only continue to cool and eventually will radiate weakly in the radio spectrum, as Jupiter and other large gas plants do. However, at some points they may have pretty respectable surface temperatures (perhaps as high as 2500K). At the core they also may fuse some paltry amounts of deuterium and tritium.

On technical grounds this should justify calling them stars, if only briefly. On aesthetic grounds I also think these objects should be cut a bit of slack. The universe is cold and empty enough. Stripping these pitiful gas balls of star-hood entirely seems a bit too harsh.
Re:Awesome! by jfengel · 2004-09-11 03:29 · Score: 1

Thanks for the interesting analysis. The article sez, "An analysis of its emissions found it contains water, which suggests its mass is in the range of planets rather than stars." (That's from the article; for some reason the preprint didn't render for me.)

If the red object is a star, could it contain water? Or something in the spectral lines that might look like water?

It certainly doesn't look like what I'd expect a planet to look like in a photo (not that I'm an astronomer or anything). It's awfully bright to be a reflective object. Maybe that photo is retouched?
Re:Awesome! by Shigeru · 2004-09-13 09:16 · Score: 2, Informative

As you get to the very lowest masses of the low-mass stars (about .08 solar masses, or 80 Jupiters), I think you do start getting water lines. The issue is that most stellar photospheres (like our sun's, say) are so hot you can't have molecules of any kind, whereas in cooler stars or brown dwarfs you can. Most people are at least vaguely familiar with the idea of atmoic spectra, where you get some number of sharp (more or less) lines throughout the visible, which, in theory, could be mistaken for one another (it certainly happens for some of the low-strength metal lines). Molecules, on the other hand, have large "bands" of absorption, where light over a large wavelength range is heavily absorbed. It's fun quantum mechanics, but basically the central line is some transition to do with the molecule vibrating (the distance between the oxygen and hydrogen atoms in the water molecule oscillating, say), which is then broadened by a number of transitions to do with the whole molecule rotating.

The end result is you get very distinctive molecular features. See the bottom image on this page on another way of looking for planets, where the black line is the spectrum of the first brown dwarf discovered, Gliesse 229B. Everything in that spectrum redward (longer wavelength) of 1.6 microns is heavily suppresed by methane (another common molecule, CH4)...and I think after about 1.8 you start getting into water bands, too, but don't quote me on that. Anyway, that's all a convoluted way of saying if it looks like water, it probably is water. But there's a large range of planets and brown dwarfs expected to have such water bands in the spectrum (indeed, the parent brown dwarf shows similiar spectral features to the companion)

As to the photo, the data have certainly gone through a lot of processing in the reduction process, but that shouldn't be though of as having photoshopped the result. I've used this same instrument, and there are some features I'm curious about (lack of diffraction spikes from spider arms, mainly), but it seems pretty legitimate. It's just important to realize what this image is showing.

For one thing, that isn't reflected light making the "planet" shine, but rather the planet is powering itself. When you form something like a planet or brown dwarf, and it isn't massive enough to start fusion, gravity will make the object contract. The potential energy of that contraction needs to go somewhere, so half of it heats the gas, the other half comes out as radiation (mostly infrared). As the object ages, the contraction slows, and it gets much fainter. As an aside, even after 5 billion years, Jupiter emits more radiation than it receives from the sun. That's part of the trouble with detecting planets in general, in cases like this we know how much energy is coming out of the object, roughly how old it is, and then we have to rely on theoretical models (which aren't well-tested at all) to tell us how massive the object should be.

The second point is to remember that the "size" of the two objects in that image aren't the physical sizes at all. In fact, the telescope is barely able to resolve the separation between the two, let alone physical structure of the surfaces of these bodies (a scale 10,000 times smaller or so). "Size" of the disk on the detector is simply a matter of our imperfect telescope optics (and basic physics of diffraction) taking the points of lights from parent and companion and smearing them out: brighter objects seem to reach further out on the detector. The diffuse structure near the edge of the bright parent is again introduced by the optics, and isn't a real feature.

The image itself is your typical false-color image. All the data are in the infrared, so for us to see it, a quick remapping has to be done. Rather than have red (0.65 microns), green (0.55 microns), and blue (0.45 microns) filters that are then reproduced by red, green, and blue pixels,
Re:Awesome! by jfengel · 2004-09-13 15:26 · Score: 1

What an excellent answer (answers, actually). Thank you. Always pleasant to have somebody who actually knows something about something around here.

ESO press release by Sygiinu · 2004-09-10 04:49 · Score: 4, Informative

Here's a link to the ESO press release.

But what does it look like by Marxist+Hacker+42 · 2004-09-10 05:48 · Score: 1, Offtopic

On a 1 Gigapixel camera?

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SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.

Re:But what does it look like by Anonymous Coward · 2004-09-10 06:59 · Score: 0

On a normal camera:

.

On a 1 Gigapixel camera:

.

A real stile project by orthogonal · 2004-09-10 06:11 · Score: 1

European astronomers have taken what may be the first picture of an extra-solar planet. The possible planet orbits a brown dwarf star 230 light years away.

The picture looks disturbingly like one often posted at Slashdot.

Where exactly were the cameras aimed again?

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Opinions on the Twiddler2 hand-held keyboard?

In case of Slashdotting... by k4_pacific · 2004-09-10 06:23 · Score: 4, Funny

Here's an ASCII approximation of the original phorograph:

.*

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Unknown host pong.

Re:In case of Slashdotting... by Alsee · 2004-09-10 06:56 · Score: 2, Funny

A more accurate ASCII approximation of the original photograph would be:

`

-

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- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.

trust a picture? by tucara · 2004-09-10 06:42 · Score: 1

Although it looks cool, I wouldn't trust a static frame as 'evidence' of a planet. Things like tracking it's path or spectroscopically analyzing body's emission would go further to prove things. Then again this may just be the pretty face on a whole boatload of research and I need to dig a little deeper.

Re:trust a picture? by Doctor+Fishboy · 2004-09-10 07:03 · Score: 1

We discussed this at astronomer's coffee this morning. They did take a very low spectral resolution spectrum of it and it is fairly consistent with colours from a cool planet, but a proper motion measurement (i.e. take a picture about 2 years from now and see if they both move across the sky together) will confirm it.

Dr Fish
Re:trust a picture? by CanSpice · 2004-09-10 07:10 · Score: 2, Interesting

If you read the ESO press release you'll see that in addition to imaging it they've also taken spectra of it. The H-band spectrum they shows is similar to other sub-stellar objects, and it also shows fairly strong water absorption bands. This means that it's has to be fairly light. Evolutionary models have been run that predict that this object is about 5 times the mass of Jupiter.

Don't worry, most astronomers don't base their predictions on one image of something, they always follow it up with either multi-wavelength studies or spectral analysis, or both.

Re:NASA by Anonymous Coward · 2004-09-10 06:56 · Score: 0

YOU ARE DENSE.

Unconfirmed by Theory+of+Everything · 2004-09-10 07:13 · Score: 4, Informative

This announcement was premature, at best. It is not responsible science.

The planet is not yet confirmed as such. It could very easily be a background star. This has happenned before, and the scientists got an awful lot of egg on their faces. Another unconfirmed "planet" image can be seen here, this one around a white dwarf.

The responsible thing to do is wait a few years to determine if the objects have common proper-motions--if they move through the sky together, they are probably physically linked, and one can determine that the companion object really is a planet. Without this confirmation, the simplest explanation is not that it is a planet.

Many teams of astronomers have images of planet candidates like this one. The responsible astronomers are the ones you aren't hearing from yet--the ones waiting to verify they have planets.

The press-release title should be "A dim spot imaged near a brown dwarf." Any further conclusions have no basis.

Re:Unconfirmed by novakyu · 2004-09-10 07:38 · Score: 1

Indeed. If it's bright enough to be observed optically, shouldn't your first reaction be, "Wait--this must be a binary system with a dim companion"?

The link to another page (er, something about using infrared, which supposedly is not a reflection from the star, but a blackbody radiation from the planet itself) has more credibility, but, still, they are using "infrared" there, using a tiny little (well, I don't know exactly how big it is, but since it's on Hubble, it can't be too big) telescope on Hubble: the resolution of such a picture can't be too good.
Re:Unconfirmed by joak · 2004-09-10 08:13 · Score: 1

You're confusing science and news announcements. For those of us outside the field (like, say, me) it's interesting to hear about now, instead of two years later. So what if the investigation is incomplete? You can also read about ongoing research and speculation on AIDS vaccines, neuroscience, quantum computing, etc. if you want. Nothing irresponsible about it.

And it's not like the press release says this is certain:

The definitive answer is now awaiting further observations.

On several occasions during the past years, astronomical images revealed faint objects, seen near much brighter stars. Some of these have been thought to be those of orbiting exoplanets, but after further study, none of them could stand up to the real test. Some turned out to be faint stellar companions, others were entirely unrelated background stars.
Re:Unconfirmed by Theory+of+Everything · 2004-09-10 08:19 · Score: 2, Informative

Indeed. If it's bright enough to be observed optically, shouldn't your first reaction be, "Wait--this must be a binary system with a dim companion"?

Normally the difference in brightness, or "contrast" between a star and a planet is very large--the stars is brighter by about 100 million times in visible wavelengths, and 1 million in the infrared (for something like Jupiter). However, the star in this case is not as bright as most stars--it is a brown dwarf. Brown dwarves are much, much fainter than regular stars. Astronomers know how bright brown dwarves tend to be. In this case, the astronomers measured the brightness of the companion spot relative to the brightness of the brown dwarf in the picture. The difference in brightness is such that if the companion object is equally far away from earth as is the brown dwarf, it would have the brightness one would expect a planet to be.

(well, I don't know exactly how big it is, but since it's on Hubble, it can't be too big) telescope on Hubble: the resolution of such a picture can't be too good.

Actually, the telescope used on that link was Hubble itself, not some additional instrument stuck to Hubble. Hubble is 2.4 meters in diameter. The largests single (non-interferometer) optical telescopes in the world are the Keck Telescopes, the SALT telescope, and the HET, each at 10 meters diameter. So Hubble is pretty big. Being in space, Hubble's resolution is limited only by its size. At the wavelengths Hubble works at (visible), this is about 50 milli-arcseconds (mas).

Today's announced "planet image" comes from one of Europe's 4 VLT telescopes, using adaptive optics. These are 8 meters in diameter. The resolution of these ground-based telescopes is limited by the atmosphere (seeing) and their diameters. Normally, the sky is completely dominant. In the infrared, a technique called Adaptive Optics (AO) can correct for the atmosphere in special circumstances. Right now, AO technology only works in the infrared, not at visible wavelengths. AO on a 8-10 meter ground-based telescope, in the infrared, gives a resolution of about 50 mas, same as Hubble in visible wavelengths.

It is often over-looked that AO has flaws. It only works on bright stars, so Hubble can see things much fainter, with high resolution simultaneously. Also, Hubble can look at things all over the sky--AO only works when a bright star is in the image. Of the most concern, AO is not a perfect correction for the atmosphere--some flaws remain in the image. These are extremely difficult to calibrate, making it difficult to use the data for high-precision work. But that's another topic entirely.
Re:Unconfirmed by Theory+of+Everything · 2004-09-10 08:23 · Score: 1

You're confusing science and news announcements. For those of us outside the field (like, say, me) it's interesting to hear about now, instead of two years later.

True, but nobody ever hears the part two years later when they say "oops, turned out we were wrong." It doesn't make the news. You are left instead with a mis-informed public. Then, when someone really does image a planet, and confirms it, the reaction is only "didn't they already do that?"

You are correct to point out they clarified it in the end of the article. But since many people only read the headlines, the headline itself could mislead the public. When choosing a headline, one should keep that in mind.
Re:Unconfirmed by Shigeru · 2004-09-10 09:38 · Score: 2, Informative

Actually, this is an interesting case in that if it is a false alarm, the most likely explanation is that it's a foreground brown dwarf. The ESO team seems to have a noisy spectrum and JHK photometry of the companion. The colors really do suggest an L-dwarf (as opposed to a background K star, say), and the methane feature in the spectrum does seem real, assuming those data were reduced correctly (Difficult under the best conditions, not made easier by a brighter object 0.7 arcseconds away).

But you're absolutely right, until the proper motion study is confirmed, they've got nothing besides staking their claim to the object on the chance they get lucky. The TW Hydra association (to which the "parent" brown dwarf belongs) moves on the sky at about 66 milli-arcseconds a year, so it should be possible in a few years to see if the companion is following or not.

For me, the kicker is trusting the models. All determinations of mass (including of the parent brown dwarf) are done by guessing age, measuring luminosity and/or color, and seeing what the models of brown dwarfs/extrasolar planets say the mass should be. These are cooling tracks calibrated to Jupiter at 5 billion years, predicting how bright something is at 8 million years. Even the people making the models are hesitant to trust their own numbers at the youngest ages (Heck, we don't even know how long it takes to form a large Jupiter out of the disk).

Right now, I'd set the odds at about 80% that it won't be confirmed as a proper motion pair. In which case, my guess would be a foreground brown dwarf of a much larger mass (older and dimmer, but closer to still put it at 18th magnitude in H). If I'm wrong, the open question of these thoroughly untested models remains the cloud of uncertainty hanging over all of this.
Re:Unconfirmed by joak · 2004-09-10 13:16 · Score: 1

I agree that overhyping by scientists or sloppy writing by journalists can leave the public mis-informed, but you're argument is very close to saying that accurate information should be suppressed from the masses, because they can't understand it.

There are probably be people who read this and think "didn't they already do that" because they've misunderstood the other techniques used for discovering planets. You're never going to be able to guarantee that someone who only cares enough to scans headlines will come away with actual knowledge. That doesn't mean that this news needs to be restricted to people who work in astronomy departments at universities.

Ummm... by Uplore · 2004-09-10 10:45 · Score: 1

I looked all over the linked webpage for the picture of the planet but all I could find was what looked like a picture of the power status light from one of the new lacie 1 TB external harddrives. Can someone point me to the right page please?

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I couldn't think of a sig.

More Interesting... by Undefined+Parameter · 2004-09-10 14:02 · Score: 2, Funny

It seems, from this image, linked from the ESO press release, that we've more than maybe seen the first planet out of our solar system with our own eyes.

It looks like we've also confirmed that brown dwarfs are glowing, white stopsigns. Let's just hope that no one needs to build a space lane straight through our solar system with great-big bulldozer things.

[/lame attempt at humor]

~UP

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Eat the Path.

anything nearby? by Sensei_knight · 2004-09-10 14:15 · Score: 1

Why arnt there any reports of the nearby stars? I'm sure they have to have planets too.

Parse error by Jesrad · 2004-09-10 22:46 · Score: 1

I mistakenly read this news' title as "Extra Solar panel damaged" and thought "Damn, that ISS is falling apart fast those days!". No, I had no coffee yet.

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Maybe we deserve this world ?

Ummmm .... by gstoddart · 2004-09-11 02:05 · Score: 1, Insightful

This was posted yesterday and nobody on slashdot has commented on this yet?

My god. Before '95 we suspected other planets would have to exist. Now we've not only cataloged over 120 of them but might have grabbed an image of one -- and no geek has at least said anything?

Hell, some of the really freaky planetary systems they've found are just amazing. Think of something bigger than Jupiter orbiting way closer than the Earth to Sol but doing it's 'annual' orbit in about 4 days.

Starting to get an idea of the type of solar systems that have formed just sounds absolutely cool. Lots of 'em are bound to be completely uninhabitable, but being able to locate planets is just mind-boggling.

What, no science geeks left on ./?

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Lost at C:>. Found at C.

First sentence after discovery: by wertarbyte · 2004-09-11 10:10 · Score: 0

"That's not a moon..."

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Life is just nature's way of keeping meat fresh.

Re:NASA by Anonymous Coward · 2004-09-14 13:42 · Score: 0

Sorry, my bad, apparently I put up a link to a different discovery made by NASA. I'd like to apologize to the asshole that thought a new possible planet discovered by a European organization and another similar discovery made by NASA are completely unrelated and that my post was off topic.

36 comments