We have a lot of wacky weather here on Earth, giving us crazy things like thundersnow and
fire-nados.
But it turns out we are very lucky, because things get way weirder and wilder on other
planets.
So let’s take a look at a few exoplanets, including some where it rains molten glass,
and ice is hot.
62 light-years away, on the exoplanet HD 189733b, winds are strong enough to make the rain fall
sideways.
Researchers from the University of Warwick learned about this weird world by studying
it with the La Silla telescope in Chile.
They waited for the planet to pass in front of a star, and then analyzed the starlight
that passed through its atmosphere.
This allowed astronomers to determine the composition of the planet’s atmosphere,
and also tell which way the wind was blowing, and how strong it was.
And it turns out, the winds on this planet are more than 15 times faster than the speed
of sound.
And when it rains there, it doesn’t rain water -- it rains hot glass.
Astronomers found that the planet’s atmosphere was full of particles of magnesium silicate
-- here on Earth, silicates are the main components of rocks and sand.
And this world orbits its star in a mere 53 hours, with temperatures that can range from
1000 to 3300 degrees Celsius.
So when silicate hits its melting point, at about 1900 degrees, it effectively turns into
liquid glass than can rain down through the clouds.
And when it reaches the cooler layers of the atmosphere, it solidifies into shards of glass
that then get whipped around by its supersonic winds.
So if you would like to go on vacation there, I would like a postcard, but I’m not coming
with you.
Now, this next planet doesn’t have wicked winds, in fact, it doesn’t even look like
your average planet, thanks to a cloud of hydrogen gas that follows it around like a
comet’s tail.
But astronomers didn’t know this when they first discovered the planet: Gliese 436b.
It wasn’t until they looked at the planet in ultraviolet light that they were able to
figure out what was going on.
Gliese 436b orbits a red dwarf, and it’s so close to the star that it orbits every
2.6 days.
Because the two are so close to each other, the star heats the planet’s atmosphere to
the point where the hydrogen gets all excited and starts to escape.
But once the hydrogen gets into space, it starts to cool off and condense into a cloud.
Now, you might think that radiation from the star would push the hydrogen cloud away.
But this red dwarf is too weak to do that.
So the cloud gets pulled along by the planet, stretching the cloud into a tail as it circles
the star.
Plus, with all the hydrogen escaping the atmosphere, Gliese 436b is left with heavier molecules,
which start to bond in extreme ways because of the hot temperatures and powerful gravity.
Scientists think that the conditions might be just about right to make a special kind
of water called Ice X.
Water, as you and I know, is just hydrogen and oxygen, right?
And when those molecules of H2O get cold enough, we end up with the average, everyday kind
of ice.
But Ice-X is different.
To make it, intense pressures have to force those molecules into an extremely tight configuration,
which lets the ice stay solid at temperatures over 400 degrees Celsius.
So basically, astronomers believe that Gliese 436b may be covered in ... hot ice.
If you think that sounds like a rough place to call home, stay away from this last planet.
HD 80606b is about four times as massive as Jupiter, and it has an incredibly elliptical
orbit.
It takes about 111 days for it to complete one trip around its star -- and for the vast
majority of that time, it’s pretty far away from it.
But for a span of less than 24 hours, it’s so close to its star that it creates a dramatic
temperature change -- so dramatic that it essentially causes its atmosphere to explode.
Astrophysicists at the University of California Santa Cruz realized this, while studying the
planet using the Spitzer Space telescope.
Over the course of six hours, they measured a temperature rise of about 700 degrees Celsius.
Using a computer simulation, they discovered that the temperature difference between the
front side of the planet, facing the star, and the back side of the planet, facing away
from the star, created a shockwave.
This shockwave could ripple around the planet and produce wind speeds over 17,700 kilometers
per hour.
These enormous wind storms keep raging until the planet moves away from the star, and its
atmosphere has a chance to settle down again.
Then the cycle repeats.
So when you hear people talking about the next big blizzard or polar vortex or hurricane
headed our way, just know that we’ve still got things pretty good here on Earth.
At least the next apocalypse isn’t only 111 days away.
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