Most of La Palma has good weather nearly all year. But the observatory is up at 2400 m (almost 8,000 ft) and occasionally in winter dramatic storms come howling in, dump half a metre of snow overnight, and disappear almost as fast as they came. If you’re planning a trip to the observatory between November and March, be sure to check the road conditions before you leave. You can…
The first ever artificial satellite, Sputnik 1, was launched by the Russians on October 4th, 1957. It weighed just 83.6 kg (184.3 lb) (less than me, I’m sorry to say) compared to the International Space Station which weighs 450 tonnes (rather more than I do.) Sputnik 1 had a very elliptical orbit, taking 96 minutes to complete one orbit, which means that it averaged a little higher than the…
The big telescopes at the observatory at the Roque de Los Muchachos mostly use mirrors rather than lenses. Domestic mirrors have the aluminium behind glass to protect it, but astronomical mirrors have the aluminium on top. This gives the best image, but it also means that the aluminium slowly spoils, and has to be replaced every three years or so. This is not a simple operation. The aluminium layer is…
GranTeCan is the biggest optical telescope in the world, and it’s hard to convey the sheer size of it in a photograph. The telescope itself weighs 485 tonnes. You could fit an tennis court inside the dome, and the top of the dome is 41 m above the ground. But you can’t see any of that in a photograph. Luckily for me, the engineers did some maintenance on the massive…
Astronomers have found a diamond half the size of Jupiter. Like most planets outside our solar system, nobody’s seen it. In this case, the astronomers were looking at its parent star (a pulsar) and found that the star was being pulled slightly backwards and forwards by the mass of a planet, something as heavy as Jupiter and orbiting very close to the star indeed – just 600,000 kilometres, or 1.5…
The William Herschel Telescope was for many years the biggest and best optical telescope in Europe (until GranTeCan opened in 2009). The main mirror is 4.2 m across (165″, or 13′ 9″) which astronomers call “a good light bucket”. It’s rather old as world-class telescopes go, since it opened in 1987, but it still produced excellent science. In fact data from the WHT has been used for about 1,500 scientific…