Astronomers Find Two Earth-Sized Planets Orbiting Same Star. Kepler Fist-Pump.

The Kepler observatory continues to crush it when it comes to exoplanet finds and the such. The recent most ballin’ discovery? Two Earth-sized planets orbiting the same star. Everybody drink! Woo! Or don’t drink, cause you know, it’s the middle of the work day and shit.

Bad Astronomy:

The planets are called Kepler-20e and Kepler-20f, and as you can see by the illustration above they are very close to the same size as our home world: 20e is about 11,100 km (6900 miles) in diameter, and 20f about 13,200 km (8200 miles) across. For comparison, Earth has a diameter of 12,760 km (7930 miles). This makes them the smallest confirmed exoplanets seen orbiting another star! The previous record holder was Kepler-10b, which has a diameter about 40% bigger than Earth’s.

To be clear: while these planets are the size of Earth, they are nowhere near Earth-like. The star, Kepler-20, is very much like the Sun, though a bit smaller and cooler (and 950 light years away). However, both planets orbit the star much closer than Earth does; 7.6 million km (4.7 million miles) and 16.6 million km (10.3 million miles), respectively. This is so much closer that both planets must have surface temperatures far hotter than ours, 760 °C and 430 °C (1400 °F and 800 °F). Even on the “cooler” planet Kepler-20f, it’s hot enough to melt tin and zinc.

So don’t start packing your bags to visit, even if you could spare a few million years to get there via rocket (950 light years is a bit of a hike). I’ll note that we don’t know the masses of these planets either. I’ll explain that in a moment, but given their sizes it’s expected they’ll have masses similar to Earth’s.

So this is very exciting! For one thing, it shows that Kepler can indeed find planets the size of Earth orbiting distant stars. That right away is fantastic; that’s the main goal of Kepler in the first place.

For another, it shows that our solar system is not entirely unique. We do know of several other stars hosting solar systems of their own, but those planets tend to be very massive; they’re easier for us to find. Since Kepler-20e and f are so close to Earth-sized, this is a big achievement.

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Fucking dope! Though I have to admit sometimes I get really excited about these discoveries and then realize how far, far, far away they are and I shed a solemn tear.