the wild ride of a fiery menace
Gas giants with an extremely eccentric orbit seem to have very wild and destructive years...
HD 80606b is a gas giant about 200 light years away. The temperature in its clouds could melt lead on an ordinary day. But when its radically eccentric orbit takes it from 78 million miles to just 2.79 million miles away from its sun, the planet turns into a furnace. As it gets closer and closer to the star, temperatures soar. The sudden rush of heat triggers massive atmospheric shockwaves which become supersonic winds. In only six hours, the planet's clouds are seared to around 2,240 degrees Fahrenheit.
If you were standing in front of the incoming shockwave, you would probably see a wall of hot metallic vapor coming at you in near silence. When it hits, you'd be vaporized in an instant, the wisps that used to be, well… you, rush forward with the searing winds as a sonic boom passes the point where you once stood. Because the winds can reach some three miles per second, an hour later your vaporized remains would be about 10,800 miles away from the spot where the shockwave engulfed you.
And there's one more thing to think about. With its elongated orbit, as HD 80606b swings into and out of its fiery fly by, it pushes any smaller, rocky world nearby out of the solar system or hurls it toward the star to be melted down into plasma. With a mass of four Jupiters, its gravity clears out a band of space almost 163 million miles thick in just 10 million years.
In our solar system, Jupiter's orbit actually protects the inner solar system. Around the yellow dwarf which we know as HD 80606, the ruling gas giant dismantled it. Marauding gas giants with eccentric orbits are bad news for a potential alien habitat and that's something to keep in mind when we start looking for habitable worlds around other stars with brand new telescopes.
