The Voyager space probes were launched in 1977 and visited many many planets sending back stunning images. CNET have a twelve photo article about Voyager 1 here which captures of the highlights of its mission. The spacecraft are now approaching the edge of the solar system and may soon enter true interstellar space, but it is their images of Earth – reverse astronomy if you like – which amaze me most. I feel a true sense of awe – amazement and fear – at the delicacy and isolation of Earth. In the image above you will need to click on the image to enlarge it sufficiently to see the Earth as a tiny bright dot.
Amazingly the picture above was sent back from 4 billion miles away with a 7 watt radio transmitter – essentially the power of bright torch bulb – barely more powerful than a mobile phone. The technology is as inspiring as the vision of the people who planned and executed this mission. Wow!