55 Cancri e Shows Off Its Blanket of Air

Well, this is kind of cool. Or, actually, it’s rather dry and hot.  The 55 Cancri has a super-Earth planet orbiting around it with some unusual properties. Astronomers used the Hubble Space Telescope to study its atmosphere as this distant world transited across the face of its star. That way, they could study the star’s light as it traveled through the planet’s atmosphere and then deduce something about the conditions on 55 Cancri e.

So, what’s the weather like there?

Turns out it’s dry. Really dry. As the international team of scientists found out, there’s not a trace of water vapor in the blanket of gases smothering this planet. And, since the planet is orbiting very close to its star, conditions are likely too hot to support things like oceans and rivers and lakes on this world. The surface temperature is around 2000º C (that’s 5,432º F, which is only somewhat cooler than the visible surface of the Sun at 7,800º F).

Exploring this Super-Earth

Astronomers call such worlds “super-Earth” because they have a mass larger than our planet’s, but are still much smaller than the really massive, large planets such as the hot Jupiters, super-Neptunes, and so on.

This particular super-Earth is a bit different from some of the others that astronomers have studied. A year there lasts for only 18 hours. That’s because it orbits so close to its star.  Now, that’s a good thing if you want to study a star’s atmosphere because it gives you a LOT of chances to watch as it transits the star. And, using Hubble Space Telescope, and in particular, the Wide Field Camera 3, astronomers were able to analyze the atmosphere and detect the gases hydrogen and helium — the first time this has ever been done with a super-Earth.

There’s a lot more to learn about this world from the HST data gathered, and I’m pretty sure that astronomers are going to use this as a springboard to study even MORE of these massive Earth-size (but not necessarily Earth-like) worlds. Stay tuned!