Sen: Probing the planets around HR 8799.

Sen: Probing an Alien Solar System

Sen: Probing an Alien Solar System

Bad Astronomy
The entire universe in blog form
April 21 2015 12:44 PM

Sen: Probing an Alien Solar System

HR 8799
Direct image of planets orbiting another star, HR 8799.

Photo byA.-L. Maire/LBTO

In 2008, the nearby star HR 8799 earned a place in the history books: It was the first star orbited by multiple planets directly seen in photographs. This was quite an accomplishment; stars are billions of times brighter than planets, so getting actual direct images of the planets is incredibly difficult. And here, orbiting this star, four have been discovered!

In the years since, the system has been extensively studied, but it’s still difficult. That’s why a team of astronomers created LEECH—the Large Binocular Telescope Exozodi Exoplanet Common Hunt.* This system is optimized to look at the exoplanets around nearby stars and create a base of observations from a single telescope and camera. Most exoplanets are observed by different telescopes, which introduces uncertainties when you try to compare the observations. Using LEECH should reduce that considerably.

Advertisement

I wrote about this, and the conclusions about the HR 8799 system found, in my biweekly column for Sen.com. It’s subscription only, but for about the cost of a magazine subscription you get a lot of good stuff. And, of course, there’s a ton of free content on the site as well. You should check it out.

*"Exozodi" refers to zodical light, the glow due to dust orbiting stars. This happens in our own solar system, and can be seen from exceptionally dark sites.