Earth's polar vortex has been in the American news all week. But we're not the only planet that has one; basically every world that has an atmosphere has a polar vortex. Here are lots of pretty pictures and animations of polar vortices.
It took months of work (and no wonder) but the wait was worth it: here is Cassini's spectacular view of Saturn, captured on July 19, 2013, as Cassini passed through Saturn's shadow. If you're a little confused by the image, I'm here to help: I've posted a video explainer.
I try to be measured in my praise for spacecraft images. Not every photo can be the greatest space image ever. But this enormous mosaic showing the flattened globe of Saturn floating within the complete disk of its rings must surely be counted among the great images of the Cassini mission.
With the recent announcement by NASA that the 36 year-old spacecraft Voyager 1 has officially entered interstellar space at a distance from the sun about four times further than Neptune's orbit, and with Voyager 2 not far behind, it seems worthwhile to explore how humans managed to fling objects so far into space.
Here it is: the view from Saturn of our Earthly home, one and a half billion kilometers away. We see Earth and the Moon through a thin veil of faintly blue ice crystals, the outskirts of Saturn's E ring. Earth is just a bright dot -- a bit brighter than the other stars in the image, but no brighter than any planet (like Saturn!) in our own sky.