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Saturday, October 23, 2010

Life on Other Worlds: Neptune by Murphy Anderson (1948)

Planet Comics #56, Sept., 1948; Fiction House
Art by Murphy Anderson
Observations from NASA's Spitzer Space Telescope reveal a distant planet with a warm spot in the wrong place.
The gas-giant planet, named upsilon Andromedae b, orbits tightly around its star, with one face perpetually boiling under the star's heat. It belongs to a class of planets termed hot Jupiters, so called for their scorching temperatures and large, gaseous constitutions.

One might think the hottest part of these planets would be directly under the sun-facing side, but previous observations have shown that their hot spots may be shifted slightly away from this point. Astronomers thought that fierce winds might be pushing hot, gaseous material around.

But the new finding may throw this theory into question. Using Spitzer, an infrared observatory, astronomers found that upsilon Andromedae b's hot spot is offset by a whopping 80 degrees. Basically, the hot spot is over to the side of the planet instead of directly under the glare of the sun.

They've guessed at some possibilities, including supersonic winds triggering shock waves that heat material up, and star-planet magnetic interactions. But these are just speculation. As more hot Jupiters are examined, astronomers will test new theories.

"We really didn't expect to find a hot spot with such a large offset," said Ian Crossfield. "It's clear that we understand even less about the atmospheric energetics of hot Jupiters than we thought we did."

This animation illustrates an unexpected warm spot on the surface of a gaseous exoplanet. NASA's Spitzer Space Telescope discovered that the hottest part of the planet, shown here as bright, orange patches on the surface, is not directly under the glare of its star but over to the side. link

Ref: A NEW 24 μm PHASE CURVE FOR υ ANDROMEDAE b. 2010. I.J.M. Crossfield, et al. Astrophyscial Journal 723: 1436.