Another extrasolar planet, now called HD 219134b was just discovered, and it’s actually a rocky planet, like Earth. It’s also the closest rocky planet (a super earth!) discovered this close to our own solar system. Huzzah!
HOW FAR IS THIS MAJESTIC SUPER EARTH?
Too far for you to walk or drive. Or fly, for that matter. The super earth, HD 219134b, is 21 light years away, but it is possible for us to explore the planet someday.
This newfound planet is also a “transiting” world, meaning that, from our perspective, it crosses in front of its host star. Of course we can’t see it from Earth, even if we had the most powerful telescopes at hand, because its star is so bright in comparison. Imagine trying to see a bird descend from the sky in the same line of sight as the sun.
SO HOW DO WE DETECT EXTRASOLAR PLANETS?
When a transiting planet passes in front of its host star, the host star’s brightness drops a significant degree because some of that light is being eclipsed by the transiting planet. This means we can measure the drop in brightness, and therefore, infer the planet’s mass and size. From here, we can calculate the planet’s density, and with that knowledge, we can know whether the planet is rocky like Mars, Venus or Earth, or gaseous; like Jupiter, Saturn or Neptune (or even icy, like Pluto).
“Transiting exoplanets are worth their weight in gold because they can be extensively characterized,” said Michael Werner, the project scientist for the Spitzer mission at NASA’s Jet Propulsion Laboratory. “This exoplanet will be one of the most studied for decades to come.”
New data on this extrasolar planet HD 219134b, set to be released soon after publishing, will be available through the journal Astronomy & Astrophysics. This data shows, among other things, that the massive exoplanet is 4.5 times Earth’s mass, and roughly 1.6 times the diameter. This is relatively close to Earth’s size and mass, when compared to the “Earth-like” planets” scientists are usually getting so excited about.
SO WHAT’S KEEPING US? LET’S GO!
The problem is that this newly discovered super earth is much too close to its sun for it to harbor life–whether originated or transplanted. It orbits its star once every three days. This planet, and all of its properties were confirmed using only NASA’s Spitzer Space Telescope, but scientists hope researchers will soon focus many more telescopes on the new find.