Transit of Mercury
No one alive had seen Venus transit when the 2004 one occurred. And if you missed that and the 2012 transit, there isn't another until 2117. However Mercury also transits the Sun – and these transits happen more often. But what's a transit and what do we learn from it?
Yuri Gagarin – The First Spaceman
On April 12, 1961 with a “Let's go!”, the first spaceman blasted off. There was no fanfare or countdown when Yuri Gagarin in Vostok 1 became the first human to orbit the Earth. He was an exceptional individual who came from humble beginnings, and at 34 his life ended all too soon.
10 Amazing Facts about Mercury
Mercury was a mystery planet for a long time. It's so close to the Sun it's only visible around sunrise and sunset, and the Sun's glare wipes out surface detail. Space probes have now studied Mercury, and it turned out to be full of surprises.
Cancer the Crab
Cancer the crab scuttles across the late winter sky, well away from its nemesis Hercules. Cancer is a zodiac constellation, the Tropic of Cancer is named for it, and it has existed for over three thousand years. Yet it seems to be a dim and unremarkable constellation. Why all the attention?
Light Pollution – Facts for Kids
Thieves are stealing something that belongs to you. It's something you inherited from countless generations of your ancestors: a view of the night sky. The unnecessary lighting that hides it also damages wildlife, increases air pollution and can damage your health. What can we do?
Scale of the Universe 2 - website
How big is the Universe? And how small? This website takes you from yoctometers - unbelievably small - to yottameters – just as unbelievably big. Navigate up or down from the human scale, with drawings and diagrams that make sense of the numbers. A great tour for everyone.
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