The First Exomoon?

Astronomers have found one of the best exomoon candidates based on data collected by the Kepler spacecraft. Now they just need the Hubble observations to check if it exists.

Saturn's Moons

This image from the Cassini spacecraft shows four of Saturn’s moons and the outskirts of the planet’s rings. Saturn’s largest moon, Titan, is in the background. In front of it and above the rings at center is Dione, one of the mid-size moons. The small moon Pandora orbits beyond the rings on the right of the image. Finally, Pan peeks out as a spot in the Encke Gap of the A ring on the left of the image. Credit:NASA / JPL-Caltech / Space Science Institute

Astronomers have found thousands of exoplanets orbiting their host stars. Yet, despite thousands of observations, one type of detection has proven elusive: the signal of an exomoon.

Check out my article at Sky & Telescope detailing the latest news from the Cool Worlds Lab at Columbia University.

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Brown Dwarfs and their Big Siblings

My latest article is up at Sky & Telescope.  I discuss two recent studies suggest that brown dwarfs, or so-called “failed stars,” are nevertheless more like stars than planets.

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Artist Conception of a Brown Dwarf Atmosphere / NASA JPL

Brown dwarfs are the exceedingly common runts of the stellar litter. But even though they’re everywhere, their faint glow makes them difficult to observe and understand. Two recent studies shed light on the formation of these once-exotic objects.

First proposed as an idea in the 1960s and finally discovered in the 1990s, brown dwarfs bridge the gap between the smallest stars and the largest planets, never igniting hydrogen fusion in their cores. They cool off over time, slowly shedding the nascent heat leftover from their formation as a dim glow.

Read more here!

A feeble giant appears

So much of our night sky has yet to be mapped by large, deep surveys.  A recent paper highlights the importance of ongoing work, as astronomers have just iddes-dwarf-galaxy-candidates-480px-300x171entified a new companion galaxy to our Milky Way.  Named “Crater 2” this galaxy is the fourth largest discovered around our Galaxy, and is quite distant, nearly 400,000 light years away.  You can read more about Crater 2 and my take on it over at Sky and Telescope.