First Reflected Light From an Exoplanet Seen

Roland Piquepaille writes "European astronomers have for the first time ever been able to detect and monitor the visible light that is scattered in the atmosphere of an exoplanet. Designated HD 189733b, also known as a 'hot Jupiter,' orbits a star slightly cooler and less massive than the Sun about 60 light-years from Earth. According to a Zurich news release, 'Polarization technique focuses limelight,' the researchers used 'techniques similar to how Polaroid sunglasses filter away reflected sunlight to reduce glare. They also directly traced the orbit of the planet, a feat of visualization not possible using indirect methods.' The team thinks that their findings are opening new opportunities for exploring physical conditions on exoplanets."

Comments

you dont want to know.

[User 956]

Designated HD 189733b, also known as a 'hot Jupiter,'

I've given my girlfriend a "hot Jupiter" before, but I didn't know it had an official scientific serial number.

Re:you dont want to know.

[Anonymous Coward]

I think you missed by two planets

If only...

[Scutter]

If only there were some sort of multi-media-enabled information sharing platform available so that everyone could see the visualizations for themselves. Oh well.

Re:If only...

[LiquidCoooled]

Mirror of image here: o.

Polaroid Sunglasses?

[parcanman]

"...the researchers used 'techniques similar to how Polaroid sunglasses filter away reflected sunlight to reduce glare..." Funny, I didn't even know Polaroid made sunglasses, here I thought they only made photography stuff. I assume the writer meant Polarized sunglasses?

Re:Polaroid Sunglasses?

[jcaldwel]

You are right, Polaroid is a name brand, but they do make sunglasses.

One definition from Dictionary.com: a brand of material for producing polarized light from unpolarized light by dichroism, consisting typically of a stretched sheet of colorless plastic treated with an iodine solution so as to have long, thin, parallel chains of polymeric molecules containing conductive iodine atoms. It is used widely in optical and lighting devices to reduce glare.

... it doesn't just refer to the cameras.

Re:Polaroid Sunglasses?

[Angry Toad]

A million years ago when I was a young one, calling them "Polaroid sunglasses" was actually pretty standard. The text probably reflects the age of the person who put the release together.

Re:Polaroid Sunglasses?

[Anonymous Coward]

It's no coincidence that polarized sunglasses have a name similar to Polaroid. Edwin Land, the inventor of the Polaroid camera, also invented the polarized film used in sunglasses. And the Polaroid company had the patent for that (then) new kind of polarizing film made by laying crystals down on plastic.

Exoplanet

[blue l0g1c]

Dear scientists, thank you for finding me.

XO -planet

Re:Where is the picture?

[4D6963]

The picture would show nothing more than a blurry spot, with one pixel slightly different from the others.

Yeah, but now, that pixel's spectrum would be quite interesting.

more info

[jack455]

It's got a wiki page as well. It's listed as only 15% more Massive than Jupiter.

"Hot Jupiters (also called roasters, epistellar jovians, pegasids or pegasean planets) are a class of extrasolar planets whose mass is close to or exceeds that of Jupiter"

I figured Hot Jubiter implied "hotter than" but I guess that's not the case.

Re:more info

[ZombieWomble]

It does imply "hotter than", if you quote the full definition from the article you cite:

... but unlike in the Solar System, where Jupiter orbits at 5 AU, the planets referred to as hot Jupiters orbit within approximately 0.05 AU of their parent stars, about one eighth the distance that Mercury orbits the Sun. Being only 1% as far away from their parent star does imply they would be significantly hotter than Jupiter (I say imply because I can't be bothered to work out the exact numbers on whether it would be feasible for such a planet orbiting a very cold star to be colder than Jupiter. I doubt it, but don't want to go around throwing out absolutes without basis).

Re:more info

[Artifakt]

It depends on whether such a planet could survive the blow offs that occur as the parent star enters a white dwarf stage. Low mass helium core white dwarfs as small as 0.11 solar masses do exist, probably as the remnants of what were originally already very small stars, but there's some question how such a small star ages fast enough that any have already blown off surface layers and collapsed. For example a star of only 0.7 standard solar masses is expected to end up as a white dwarf of about 0.4 solar masses, but stars starting even that small should have a lifetime of close to 14 billion years, so white dwarfs that proportionately small or even smaller shouldn't have had time to form by conventional means yet. There is a phenominon called Roche lobe mass transfer that could give rise to very low mass dwarfs, which would now be in binary systems, chiefly with pulsars as companion stars, but the process of forming the pulsar itself would be the sort of thing that would definitely blow a lot of a gas giant's atmosphere away into interstellar space even if the conventional small sister star's collapse was energetically light enough not to.
      Could some planet start as a 10 Jupiter mass close in giant, and end up with 1 or 2 Jupiter masses left after a big star just a million miles or so away went through at least one actual Nova and subsequent collapse to pulsar, and then a smaller, equally near star went through a small red giant phases and collapse to a white dwarf? It sounds a bit improbable, but what if the small mass star is exactly between the gas giant and the large mass star when the big one Novas?

Note: For anyone who knows a little astrophysics, yes a typical white dwarf star is very hot, i.e. the surface temperature may be 23,000 K as opposed to our sun's modest 5,700 K, but the actual amount of heat emitted is very much smaller due to the small surface area. It takes a high mass (0.91 solar masses plus) white dwarf to have a zone around it hot enough for a planet to have liquid water at all. (So yes, they could have very close in but still cold Jovians).

Future possibilities

[damburger]

If an exoplanet can be directly imaged in this manner, does that mean some of the techniques used on stars for inferring the existence of exoplanets (wobbling, dimming etc) can be used to detect exomoons?

This would be a great breakthrough if it were possible, seeing as most of the exoplanets we know about are gas giants and if they host life it is likely to be on their moons.