Credit: Robert Hertel Today's sunlight is about 30,000 years old. It was made at the height of the last Ice Age. It has taken that long to work its way out from the core of the Sun and fly across space to the Earth
Credit: ESA/Cassini On Earth, hurricanes are always circular, never triangular or square. But, here, at the north pole of Saturn is a hurricane the shape of... a hexagon. It's twice the size of Earth and it's been raging for at least 25 years. We know that because it was seen by one of NASA's Voyager space probes as it flew by Saturn. Nobody knows what causes the hexagonal shape. Intriguingly, the hurricane at the south pole of Saturn is a normal circular one
Credit: NASA Most distant image of Earth, taken by Voyager 1 from a distance of 6 billion kiometres. How about we all remember we are all on this dot together? (Coloured bands are artefacts caused by light bouncing around in side the Voyager camera)
Credit: NASA/Spririt rover Sunset no human eye has ever seen... on Mars
Credit: NASA Will Buzz Aldrin's footprint last forever? With no wind or rain to erase it, you might think so. But, actually, the Moon is bombarded by a continual "rain" of sand-grain-sized micrometorites, which will smear out the footprint in about 10 million years. It won't last forever. But, probably, it will outlast the human race
Credit: NASA/HST There are about 15 galaxies for every man, woman and child on Earth (I'm bagging this one!)
Credit: YourTime2012 Matter is so empty that, if all the empty space were squeezed out of all the atoms in all of the 7 billion people on Earth, the human race would fit in the volume of a sugar cube
If the Sun were made of bananas, it wouldn't make much difference. This is because the Sun is hot because of the amount of matter it contains not the type. The Sun is a billion billion billion tonnes of mostly hydrogen gas. But, if a similar mass of microwave ovens or of bananas were piled in one place, the result would be something as hot as the Sun (This explains why the Sun is hot at this instant but why it 'stays' hot is another matter!)
Credit: NASA Saturn's rings are not, er, rings - they are spirals, like the spiral groove on an old vinyl record
Credit: SuperKamiokande Image of Sun. Taken at night. Not looking up at the sky but down through the Earth's core to the Sun on the other side of the Earth. Not with light but with neutrinos

[Have tried my best to find credits for all images. More than happy to rectify any omission or find a substitute image]