March 2016 saw the launch of the first part of Europe’s two-part mission to Mars. The mission, called ExoMars, comprises the “Trace Gas Orbiter” – the part that’s just launched – and a large rover, which launches in 2018. The orbiter will sniff the atmosphere to test for evidence of past – or maybe even present – life. Elsewhere in the world of astronomy, this month has also seen the discovery a cluster of “monster stars”, and the most distant galaxy ever seen. I chatted to Edward Gomez and Tim Davis, a relatively new arrival here in Cardiff, about these discoveries.
It probably didn’t escape your notice that yesterday was 29th February – a date that comes round but once every 4 years. The reason for having leap years is explained in detail by Phil Plait on his Bad Astronomy blog (which is actually quite good). It’s essentially because the Earth’s rotation and the Earth’s orbit around the Sun aren’t quite in sync. Although a year is usually 365 days long, the Earth actually takes around 365.25 to get to the same place in space around its orbit. (It’s not exactly 365.25, and Phil Plait explains the details so I’ll defer to him.) Continue reading →