Found: A Blue Planet That Rains Glass

One of the strangest and loveliest exoplanets yet gives the galaxy another pale blue dot

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Back in the early 90’s, the Voyager 2 space probe, already out beyond Neptune and on its way toward the edge of the Solar System, swiveled its camera around to look back at its home world. It was difficult to see, but there, nearly three billion miles (4.8 billion km) away, lay Earth. Our entire planet, with all its flora and fauna and history and civilizations was nothing more than a blip of blue against the background of stars—an object so tiny and frail that the phrase “pale blue dot” inspired the great astronomer-communicator Carl Sagan to write a book about humanity’s future in space.

Now astronomers are abuzz with news of a second pale blue dot—a planet orbiting the star HD 189733, about 60 light-years from Earth. It’s a tiny bit less hospitable than Earth: known as HD 189733b, the planet is a giant, gaseous world resembling Jupiter, but much hotter. With a surface temperature of 1800°F (980°C), rainstorms of glass (yes, glass) and winds that reach 4,000 m.p.h. (6,400 k/h), it’s not even remotely likely to be home to flora and fauna.

Measuring the color of this so-called exoplanet is a major scientific milestone nonetheless: it provides important clues to what the atmosphere is made of, which can in turn tell scientists something about the origins and composition of the planet itself. And while it’s not possible with current technology, observations like this one are a warmup for studies of true Mirror Earths—smaller, more temperate worlds like ours, where life could plausibly exist.

Unlike the 90’s-vintage pale blue dot, the 2013 version wasn’t photographed directly. It’s much too close to its star, and too comparatively faint, to isolate its light from that of the much brighter HD 189733. Instead, astronomers used the Hubble Space Telescope to watch as the planet, whose orbit is perfectly edge-on as seen from Earth, ducked behind its star and then re-emerged.

When planet and star are side by side, the Hubble picks up the light of the star itself plus the reflected starlight bouncing off the planet. When the planet moves behind the star, the reflected light disappears—and by making before-and-after comparisons, astronomers can calculate what the reflected light would look like in isolation.

In this case, it’s what scientists call an “azure blue”—a little more poetic-sounding than “pale blue,” but very much in the same ballpark. On Earth, the color is produced because the blue part of the Sun’s light is scattered in all directions by air molecules—eventually reaching our eyes from so many angles that the entire sky looks blue. That blue light is reflected back into space by our oceans. On HD 189733b, the same thing evidently happens—except that it’s glassy silicate particles that do the scattering, not air, and there’s no ocean to enhance the effect through reflection.

This observation is important not just because it keeps astronomers in practice for future studies, of course: it’s also crucial to understanding planets like HD 189733b—so-called “hot Jupiters,” whose very existence was completely unexpected when planet-hunters began finding them in droves in the mid-1990’s. “These new observations add another piece to the puzzle over the nature and atmosphere of HD 189733b,” said Frédéric Pont of the U.K.’s University of Exeter, lead author of the study, in a press release. “We are slowly painting a more complete picture of this exotic planet.”

The picture would be far more complete, of course, if, astronomers could send a Voyager-like probe to visit the HD 189733 system—and 60 light-years isn’t all that far away in a Milky Way that spans 100,000 light-years. If Voyager were headed in the right direction, we could even wait for that already-flying probe to get there. The bad news: at Voyager’s current speed, that would take about 1.2 million years.

13 comments
bhatnagar.pb
bhatnagar.pb

If we are, then we are not alone...The question is "WHEN"

Payingattention
Payingattention

The only way for the foreseeable future for us to get to those other planets that will support life is to die here and come into existence there.  Unfortunately, this mode of travel wipes out any memory of where we once were.  If I am correct, then Earth is simply one stop on our tour of the universe.  

Even though all our senses tell us the universe is "out there", in truth the picture we see is really inside our heads.  As we study that picture, it becomes clearer and more meaningful.  To me it is becoming clearer that the entire universe is our creator.  And like the tree falling in the forest, it needs an observer to turn pressure waves or light waves into sounds and colors.  

The universe is infinitely large so the words of the someday to be considered a prophet, Carl Sagan, there are an infinite number of chances for life to exist somewhere in the universe as it does here on earth.  Also, I learned in school that no matter how small a number you multiply by infinity, it still equals infinity.  So, as instruments get better we're likely to get a glimpse of where our next life will be lived.

MrPeach
MrPeach like.author.displayName 1 Like

@PayingattentionRest assured, you are wrong. When you die, you're dead.

intrepidis
intrepidis

@MrPeach How do you know this with such surety? If you're only made of particles that are simply reacting then you'd just be a robot with no self-awareness.

pds3.14
pds3.14

@intrepidis @MrPeach No, you'd be a robot with self-awareness.

Having a soul is like having a creator, it just kicks the perceived problem of consciousness another step away and makes a much more severe problem of trying to explain a reasonable way for metaphysics to work.

What Payingattention was saying and what I don't agree is true, is that "we" reincarnate on another world in the future after dying. What I fail to see is how their consciousness has anything to do with ours.

Unnamed
Unnamed

@ShayneO'Neill @intrepidis @MrPeach There's a reference to self (between the words "one" and "got") there, and I'm not sure you entirely understand what it refers to.

I'm not sure anyone does. The definition has never really been formally established - though certainly not from a lack of trying. Everyone's tried a hundred times over: the legal, the scientific, the religious, the philosophical, etc. to no precise consensus.

Claiming to know exactly what constitutes "us" isn't all you did though. You decided what "it" is capable of, limits. You seem to think you can not only identify something vague and ambiguous, but set rules, authoritative and absolute.

Observing you is as far as I'll go, I won't make assertions of my own. That would forfeit skepticism, the cause of research and discovery, be it arcane or mundane. My stance of doubt extends to the claims of all individuals involved here. Gains of understanding, whether private or humanity's cumulative, usually grant visibility of new questions and uncertainty to explore.

TLDR you can't learn more if you're talking out your ass

JoshuaPerry
JoshuaPerry

The Juan de Fuchua trench provides solid evidence that a temperate climate is not a determining factor to the feasibility of life. 

pds3.14
pds3.14

@JoshuaPerry Also, "life" or life.

That is to say, are we talking about extremophiles or creatures and plants.

Also, we still need water to exist for life, putting the habitable zone in the region where water can exist somewhere on the planet (hypothetically, that means any planet warm enough for water that is tidally locked can never necessarily be too hot.)

MrPeach
MrPeach

@JoshuaPerryFuzzy thinking. This is not just not temperate, it is inimicable to any sort of life as we know it. Water cannot exist in liquid form on a planet this hot.

labt3k94
labt3k94

How exactly is it that you can tell me what the rain and surface temperature of this pale blue dot is, yet it's "far too close to it's star" to even photograph from a distance? Just curious.

pds3.14
pds3.14

@labt3k94 You can learn a lot about the composition simply by the light it gives off.

For example, a planet far from its sun giving off lots of light indicated by a 2700-kelvin source at night would be a prime target for communication, as such as source is indicative of incandescent light.

One which is not reflecting the red and green light of its star is likely a blue planet.

If it has certain absorption lines, one can infer glass as part of its atmosphere.

ZacPetit
ZacPetit

@labt3k94 Distance from sun and orbit speed will give you mass, color spectrum will give you candidates for atmospheric make-up, mass and distance from sun will eliminate several of those. It is probably a guess at best, though.