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First Exoplanet To Be Seen In Color Is Blue
ananyo writes "A navy-blue world orbiting a faraway star is the first exoplanet to have its colour measured. Discovered in 2005, HD 189733 b is one of the best-studied planets outside the Solar System, orbiting a star about 19 parsecs away in the Vulpecula, or Fox, constellation. Previous efforts to observe the planet focused on the infrared light it emits — invisible to the human eye. Astronomers have now used the Hubble Space Telescope to observe the planet and its host star. Hubble's optical resolution is not high enough to actually 'see' the planet as a dot of light separate from its star, so instead, the telescope receives light from both objects that mix into a single point source. To isolate the light contribution of the planet, the researchers waited for the planet to move behind the star during its orbit, so that its light would be blocked, and looked for changes in light colour. During the eclipse, the amount of observed blue light decreased, whereas other colours remained unaffected. This indicated that the light reflected by the planet's atmosphere, blocked by the star in the eclipse, is blue."
Let's call this place "Eiffel 65".
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I'm curious: what are the likely elements and molecules that would cause the blue reflection?
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Ah, but Neptune is named for a water god, which totally refutes your point and isn't a non-sequitur at all.
Isn't that the area the Androsynth mysteriously disappeared from? Watch out! The Orz will come after us next if we are noticed.
Did they find the Androsynth living there?
So this planet might have a breathable atmosphere. But odds are it's more methane-based.
Still, pretty nice we can observe a planet's color.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
What? No one ever said this planet might host life. According to TFA it's a gas giant.. And last I heard gas giants don't host life.
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At the least, I'm sure there's no life on Uranus.
Slow down, cowboy! It has been 4 hours since you last posted. You must wait another few hours.
Are you suggesting that the planet orbits its star at such a high speed as to produce an observable doppler shift?
you might have read the article about this being a gas giant with 1,000+ degree C atmosphere, with sideways 7,000 KPM wind containing glass particles that make the blue color. but instead you had to reflexively yank your own leash and bark a bunch of nonsense. Maybe the reason governments haven't come out with information about extraterrestrials is that you imagine it from non-existent evidence?
I mean, look at all this time and effort we're wasting on "science" and "discovery."
We need to get back to 16th century thinking and government funded services so my taxes can go down another $10 a paycheck. I mean, those cigarettes and premium cable TV channels aren't going to pay for themselves!
Is it just my observation, or are there way too many stupid people in the world?
The planet has a surface temperature of about 1000 degrees Celsius. It is scourged by 7000 km/h winds. Pieces of silica, or if you prefer: glass, are flying around at supersonic speeds. And yes, it is the silica and the glass that give the planet its blue color. We should not call it Eiffel65. We should call it Philip.
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I am not an astronomer; any chance that the coloration could be affected by something in between? For example these so called "wrinkles" that Voyager is experiencing as it exits the solar system? Just curious.
The last I had heard, we were nowhere near determining whether that was so. It seems improbable that a gas giant would, but until we actually have a reasonably decent sample size of gas giants under close observation, I'd say it's awfully premature to jump to conclusions.
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Since parsec is an antiquated unit, this planet is about 62 light years away. (or, more usefully: 2.914 quadrillion furlongs)
Wow. I actually got to be pedantic about units and none of the units involved were metric!
In other words, it's about 1.6 Kessel Runs? But how fast is that?
John
Where are the pictures? (even if one pixel wide)
I don't know. You tell me. I don't know what the orbital period for this planet is or the distance it orbits at. Orbital speeds are pretty fast though. Google tells me that the earth moves about 107,000 km/hr around the sun. If their instruments are sensitive enough, they might see the difference. I would also guess there is a possible gravitational redshift and lensing depending on the mass of the star and the orbital distance.
No, I did not RTFA, but the first thought I had was; if the planet is between us and its star, we'd be "seeing" the side of the planet facing away from the star. Wouldn't it be dark? It's not like it's a binary system with another star lighting the opposite side. Since it's a gas giant, I guess there would be enough light filtering through the upper atmosphere edges to cast off some light, but overall, it seems like such a small area to glean colors from.
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The redshift used to measure the speed of objects moving away from us applies primarily to the galaxy as a whole. If you were to normalize the light received to compensate for the redshift of the galaxy as a whole, the additional velocity of the planet, being negligibly small with respect to your new frame of reference would not significantly 'redden' your results. Good question though.
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Several times in TFS, it says that the planet is "eclipsed" by the star. This, of course, is nonsense: the correct term is "occluded," and the event is called an occultation.
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The planet isn't blue. The blue light that got blocked out by the host star was actually the trillions of blue LEDs that the natives use to light their cities, just because they happen to really fancy blue.
It seems improbable that a gas giant would
Does it seem improbable to you? Life on Earth evolved in a fluid.
Even if genesis is not possible in a gas giant atmosphere, large planets tend to have lots of moons and, therefore, lots of opportunities for primitive life to emerge. Extremophiles from such a moon could survive a short trip through space to a gas giant's atmosphere. Some small fraction of those would thrive and evolve in the new environment.
I suspect gas giant atmospheres may actually be very fertile. Life is good at producing simple sphere shapes needed for buoyancy. There are probably gas giants with billions of tons of biomass drifting around.
Lurking at the bottom of the gravity well, getting old
I don't know. I've heard Uranus is crawling with worms.
Probably not. from the parent stars perspective the doppler discoloration is based on motion along the axis between the star and the planet. It would get much LESS doppler effect as the planets motion will be extremely low along that axis, or no motion if the planets orbit is highly circular.
Not really. If the planet is passing directly behind the star, its vector of motion is perpendicular to the direction of observation and would produce no doppler effect. The doppler affect only matters for motion towards or away from the observer.
when a planet begins to transition behind its star, we would be seeing the bright sunward side of the planet, so the measure is still useful. We would only be seeing the full dark side of the planet when it passed in front of the parent star.
Yes, the colors are measured from that area.
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Thanks for clearing that up.
Vulpecula - Little Vixen, it differs slightly in connotation from the article's translation of Fox.
He effected a bored affect.
Fuck that shit! It's light years around here buddy!
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It's also known as an "ice giant".
> Life on Earth evolved in a fluid.
Actually, last I hear the going theory was that life probably evolved on submerged surfaces. Technically in a fluid, but able to borrow structure from the solid substrate, facilitating the development of more complex structures which eventually evolved self-stabilization and the ability to become free-floating. Seething chaos is great for simple chemistry, but nano-mechanical machines like early versions of RNA and enzymes likely benefited from a buffer.
The rest are good points though, and I'll add that we have only the vaguest idea as to what might be going on in the hearts of gas giants - could be the hot diamond beds of Jupiter's hydrogen seas are actually wonderfully nurturing environments for proto-life, not that I'd put money on it.
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Certainly. We've already managed to locate a few planets based on the miniscule doppler shift of the star as it orbits its system's barycenter (our barycenter for reference varies between about 1/2 and 3 solar radii from the sun's center). In comparison the doppler shift of the planet would be massive (on an admittedly much weaker signal)
However, it still wouldn't be an issue assuming you made your planet observation(s) immediately before/after it went behind its star - at that point its orbital velocity would be at right angles to our line-of-sight, so no doppler shift. Plus those are the points where the planet would be the fullest, so it's the natural time to take your measurements.
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It wouldn't be an issue assuming you made your planet observation(s) immediately before/after it went behind its star - at that point its orbital velocity would be at right angles to our line-of-sight, so no doppler shift. Plus those are the points where the planet would be the fullest, so it's the natural time to take your measurements.
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Are you suggesting that doppler doesn't work for measuring vehicle speeds, with a lower (by many orders of magnitude) velocity relative to the observer? See: RADAR gun
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Astronomy 101. Hell, even firemen know this.