The formation of our solar system, with multiple planets and other bodies of varying sizes and compositions—this was not a simple process. The more planetary systems we discover around other stars, the more we confirm the truth of this. Scientists are still working out the details of exactly why we have a system that has [...]
(This post has been edited slightly from the original to include the MESSENGER mission to Mercury and to correct a misstatement about galactic black holes.) As the end of calendar year 2011 approaches, I thought my readers might enjoy a look back at some of the key events of the year in astronomy. The usual caveats [...]
…which now makes four and counting. The new discovery comes via an eight-minute exposure (long in this context) of Pluto and its environs with the Hubble Space Telescope. Here is an image that may be a little different from what you have seen published elsewhere: This combines images from two dates (June 28 and July [...]
On the very first day of the nineteenth century, January 1, 1801, a moving star-like object was discovered by Giuseppe Piazzi in Sicily. Initially thought to be a comet and then a new planet, Ceres was eventually recognized as the first discovery of a new class of solar system objects: asteroids. William Herschel coined the [...]
