Of all the planets in our solar system, Mercury may be the most underrated. It does not have nice swirling clouds or rings or flowers. It doesn't even have an atmosphere. However, this small rocky body has a history of volcanism and even has water ice in its craters. Mercury is also locked in a special resonance with Jupiter (think of it as a billion-year-old dance partner), and there is a chance many millions of years from now that Mercury will lose its balance and be thrown out of the solar system and perhaps take Mars out on the way.
Just this week, our innermost planet got its moment when it made a rare transit and passed in front of the sun in just the right line so that people on earth could see it. That will not happen again until 2032. Only two spacecraft have ever visited lil Mercury: Mariner 1
0 1974 and 1975 and NASA's Messenger mission that revolved around Mercury from 2011 to 2015 when it was debrided and crashed into the surface. This week we will become a little more familiar with the inner world of the solar system.
The bright crater at the top of the image is called Dominici crater. Whatever hit the surface, it hit hard enough to send ejecta material out over the planet, revealing the volcanic debris and lighter material below. The entire basin has been filled with lava from volcanoes, so meteorite strikes like these that stir up dirt and rocks can help scientists get some clues as to what kind of material is beneath the surface. NASA Goddard
As you await the next Mercury transit, take a look at the rest of the space photos collection here.