Travel posters - "Exoplanet Travel Series" from JPL/NASA
Available from source
as *very* high resolution images:
If you want to read a bit more about Keppler 186f, try this g+ post
Kepler-186f, the one pictured below, is my favorite because it captures some interesting physics. It orbits a red dwarf about 500 light-years from Earth, and it was the first planet discovered which is potentially suitable (in terms of things like temperature) for life as we know it. But life would be different in some interesting ways.
One of the reasons is that photosynthesis would be a bit different. Plants on Earth are green because their leaves contain chlorophyll, a chemical which absorbs sunlight and turns that energy [explains why plant green here and red there]
Further afield (I dont honestly have a clue if it's further or nearer :p) there's been a new picture of the "Pillars of Creation" released by Hubble. Space Travel ... sort of:
Download high-res version here:http://www.spacetele...rg/images/heic1501a/
Some interesting info about how the colours in the image are mapped:
For those wanting technical details, the picture below was taken in visible light, using a "false-color" technique to make it more visible. It was photographed through three filters: an Sii filter (673nm, a fairly dark red color which is characteristically emitted by Sulfur), a H-? filter (657nm, a brighter red which characterizes Hydrogen), and an Oiii filter (502nm, a blue-green characteristic of Oxygen). Those three colors are then mapped to red, green, and blue (respectively) to form an image that clearly highlights the gas distribution to the human eye. This particular combination of light filters is the one most commonly used when photographing astronomical gas clouds.