Naomi Alderman enthuses about the Hubble telescope as it turns 20 years old.

But for those of us without faith, I propose the Hubble Deep Field Image as an excellent alternative way to get some perspective. In 1995, the Hubble telescope was pointed for 10 days at a patch of sky which appears completely blank to the naked eye from the Earth. It’s a tiny piece – much smaller than the area of sky you’d cover with your little fingernail if you held your arm outstretched. And in that apparently blank area of sky the Hubble Deep Field Image discerned with amazing clarity more than 10,000 galaxies. Each galaxy is made up, on average, of about 100bn stars. Every star could, like our sun, be orbited by planets. That is the size of the universe we live in.

This may not be a thought that makes you feel calm. Although many people find that this sense of scale helps make their own problems seem less enormous, it doesn’t work for everyone. For some the sense of how incredibly small we actually are seems to instil terror instead. But perhaps even terrifying perspective is important. In 1968, during the Apollo 8 mission, a photograph known as Earthrise was taken. It shows the Earth, from the moon, rising across the lunar landscape. This photograph has been called “the most influential environmental photograph ever taken”. The sense it gave of the Earth as small, beautiful and fragile – the understanding that, whatever our differences, we’re all together on one small planet – has been credited with kick-starting the environmental movement of the 1970s.

Full article: http://www.guardian.co.uk/science/2010/may/01/hubble-space-telescope-nasa