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Exoplanet Has Showers of Pebbles
mmmscience writes "The newly-discovered exoplanet COROT-7b has an unusual form of precipitation: rocks. Because it orbits so close to its sun, the temperature on its sun-facing side is around 4220 degrees Fahrenheit. That's hot enough for rocks to vaporize — not unlike water evaporating on Earth. And, like Earth, when the vapor cools in the upper atmosphere, it forms clouds and begins to rain. But instead of water, COROT-7b gets a shower of pebbles."
That's pretty cool, in a geeky sort of way.
I wish I could see it... but I don't think the environment would be terribly friendly to my sensitive skin.
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
We get solid precipitation here on earth all the time.
Sometimes it's hail, sometimes sleet.
The best is frogs, though.
"the temperature on its sun-facing side is around 4220 degrees Fahrenheit." For anyone using the SI, this is about 2327 degrees Celsius
True. Also, I'm wondering if "pebbles" is an appropriate description of the condensed rock or if it wouldn't be more aptly described as "sand" or even "dust". Raindrops stick together; depending on how quickly the rock condenses, it might not have time to grow very large. (Then again, it could grow like hail, if the rock was in the liquid state for any significant amount of time.)
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
Given that different material will have different melting temperatures, that should lead to the different metals coalescing at different heights. At sunset, there ought to be a layering affect as the last rocks fall back to the surface, a rock rainbow in effect. Of course, it probably won't last long with the whole planet being molten.
Be relentless!
To be fair, the original press release also mangles observed and simulated results like crazy. They've definitely found the exoplanet and determined its orbit and mass. They've either confirmed or hypothesised from simulation that there are no volatile compounds on or around the planet, which they hypothesise is due to bake-out. They've hypothesised based on simulations that it is likely to have a rock-based atmosphere which, depending on composition, could be verified spectroscopically.
No kidding!!! What do you say at this point?
Teacher: Why are you late?
Student 1: I was throwing pebbles in the pond.
Teacher: (to student #2) Why are you late?
Student 2: I was throwing pebbles in the pond.
Teacher: (to student #3) Let me guess - you were throwing pebbles in the pond too?
Student 3: I'm Pebbles.
It is nearly impossible to imagine a deluge of pebbles falling from the sky, or turning on the morning forecast to hear reports of "rocking" instead of "raining."
Oh I can imagine it. You see dark clouds roll in, crowding around. In the distance but growing louder, the rapid heavy percussion of the rock shower begins. Then in the cloud at the front, you see a flash of light and a shower of sparks like a pyrotechnic burst. Seconds later, instead of a crash of thunder, you hear the wail of an electric guitar.
It is now rocking. Rocking hard core.
This is the awesomest planet ever.
The enemies of Democracy are
ROCKS FALL! EVERYONE DIES!
That has happened on Earth too. We call it Fallout.
I am not kidding. A surface nuclear burst in the megaton range will vaporize millions of tons of rock and soil. This material will cool, condense, and and fall as
little pebbles or hail. In this case, it's radioactive, but otherwise the physics is the same.
The sky is falling?
More like the ground is falling...from the sky.
With the first link, the chain is forged.
Meanwhile on COROT-7b scientists find a new planet so cold that water would actually create "oceans" on the surface , and even freeze at the poles.
They laugh at the though ever existing on that planet.
Cruise TT
So it's like Australia?
Some hyperbole here.
The Castle Bravo test shot (http://en.wikipedia.org/wiki/Castle_Bravo) was one of the largest thermonuclear detonations ever, with an estimated yield of 15-22 MT. The blast crater from Bravo was 2000m in diameter and 75m deep. Assuming it was square because I'm too lazy for math today, that's about 300,000 cubic meters. Assuming that this was blasted in solid granite (http://www.allmeasures.com/Formulae/static/materials/32/density.htm) you get about 780k metric tons.
However, most of this material wasn't vaporized, it was pulverized by the shock wave and propelled as a solid into the mushroom cloud. The actual quantity of material melted I wouldn't hazard to estimate, but it was a small proportion of the overall material excavated.
Much as in the "it's raining rocks!" planet, this precipitation would be much closer in form to dust, not "pebbles". One of the reason that water on earth comes in larger forms is that the water molecule has a charge, and will aggregate electrostatically. I don't think that would be true of this silicate cloud.
bite it noobs
forgot to check the AC box? noob!
ow!
Best Slashdot Co
...and if you like pina coladas and getting bludgeoned in the rain...
What I find interesting about this planet is that it's tidally locked with it's star, so one side is over 4000F, while the other is -370F. That could imply that the surface continuously evaporates on the hot side and condenses out of the atmosphere on the cold side. So the planet is essentially a conveyor belt always in the process of being destroyed and created. The contents of the entire planet could have gone through this process many times already.
Of course! Everything is made of Uranium on uranus, of Plutonium on Pluto, and Titanium on Titan. And Hafnium on the planet Haf, but that hasn't been discovered yet.
"The plural of anecdote is not data" -- Bruce Schneier
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