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Hot Giants II

StarDate: 
January 24, 2018

A trip to a planet that appears near the Northern Cross might find visitors pining for the south pole. That’s because dayside temperatures on the planet soar to almost 8,000 degrees Fahrenheit — hotter than most of the stars in the galaxy.

The planet is known as KELT-9b. It’s named for a network of small telescopes that hunts for planets.

The star in this system is the hottest star with a planet yet seen. And the planet orbits just a couple of million miles from the star. The combination makes it the hottest planet yet discovered.

KELT-9b is locked so that the same hemisphere always faces the star. So it’s always daytime on that hemisphere, which helps crank up the thermostat.

The star may be destroying the planet. In part, that’s because the planet probably is built like Jupiter, the giant of our own solar system — a thick envelope of gas wrapped around a rocky core. The star’s energy acts like a blowtorch, blasting away the planet’s atmosphere.

By the time the star reaches the end of its life, in a couple of hundred million years, there may not be anything left of the planet but its core. And that won’t last long, either. The star most likely will ingest whatever is left of KELT-9b, destroying the last remnants of this hellish world.

For now, though, the system lines up near the star at the center of the Northern Cross, which is in the west and northwest as darkness falls.

We’ll have more about exoplanets tomorrow.

Script by Damond Benningfield

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