The website io9 is a rich source of information on all things scientific and cultural. Below are three items with an astronomical theme.
- Planet ~ In our solar system, Mercury's orbit lies closest to the sun, and until quite recently we had little understanding of its geology or even its rotation. Thanks to this NASA video, a composite of images taken by the MESSENGER probe (recall that Mercury was the messenger among the Roman gods) reveals impact craters, volcanic plains, and much more. Look below the video to find background on the planet, and an explanation of the color coding in the images.
- Star ~ Here is a spectacular image of a year's worth of solar storms on our sun, recorded by the orbiting Solar Dynamics Observatory. You are seeing the sun not in visible light wavelengths, but rather in extreme ultraviolet light. Ionized atoms in subsurface upwellings into the sun's corona reach temperatures of 1 million degrees Farenheit.
- Galaxy ~ Just as moons orbit planets, and planets orbit stars, and stars orbit around the center of their galaxies, so do galaxies can orbit around each other ~ in pairs or in groups. Our own Milky Way galaxy has two smaller companion galaxies. The Large and Small Magellanic Clouds (LMC and SMC) orbit each other, and the pair in turn orbits the Milky Way. NASA's Swift satellite has closely surveyed both galaxies, allowing the creation of this sweeping image of all three star clusters. At the same link there is a video which explains what you're seeing.
Go in peace.