1.99 x 10^30 kilos

Oh dear, rather a dull blip I'm afraid; but it's what I've spent most of today on. Pity about the unseasonal summer weather outside. I keep reminding myself that I don't even need to pass the exam, much less to do well in it, since I'm only studying the course to check out its, erm, innovative assessment strategy. Trouble is, as the exam date gets nearer I start to feel competitive with myself. Might as well run with it, though, as the adrenalin rush on the day itself is awesome.

The list of useful constants and important equations will be available in the exam, but I've used it enough to find that I now know the value of the gravitational constant and the mass of the Sun (and Jupiter) without having to look them up. I must get out more.