Mortal as I am, I know that I am born for a day. But when I follow at my pleasure the serried multitude of the stars in their circular course, my feet no longer touch the earth - Ptolemy
How the Universe Works
I've been watching a fascinating series of programmes entitled 'How the Universe Works'. I did know a lot of stuff already but I always enjoy the graphics and computer simulations of events I'm never likely to see with my own eyes. I highly recommend the series to all, reruns are featured regularly on the Discovery channel.
For once, as the Earth sailed through the dust trail left by periodic comet Swift-Tuttle, some lucky waiting astronomers and their long-suffering partners were rewarded with a cosmic firework show. More colloquially known as the Perseid meteor shower, the celestial event was broadcast on the news channels and also trumpeted on the BBC News website. My partner and I headed out to Covenham with other members of my local astronomy club, and we clocked our first astronomical event just before 10pm, something I'd never witnessed before — an Iridium flare, which are caused by satellites in low Earth orbit reflecting sunlight. Only dedicated satellite observers can predict these flares, so to catch one unexpectedly is quite a thrill. Ours was green, looked like fork lightning and lasted around ten seconds.
Around 10pm the almost-total cloud cover had cleared in the area of sky we were interested in and we all focused on Cassiopeia and Perseus. We saw the first meteor at exactly 10pm and from then on they came quite regularly. The next hour passed swiftly as the many gasps of 'ooh!' and 'aaah!' and shouts of 'there!' punctuated the stillness of the night. I saw one which was low and thick, much bigger than other streaks. Other meteor-hopefuls around the country and globe didn't fare so well, unfortunately. However, my son reported that he'd gone out at 10pm, looked up and saw 'lots of flashes' (this from my own back garden!) but I don't regret the trip to the dark-sky viewing area (which I'm always recommending) as half the fun of witnessing a meteor shower is being with a group of other equally-thrilled skywatchers. The shower continued until at least 17 August; my goodness was I surprised to look up at a clear sky, admire the stars and see three flashes in quick succession, so I stayed out for a while and was rewarded with another half-dozen or so Perseid stragglers. Having the feeling that I was probably the only person seeing them made them all the more special.
September Diary Dates
Comet Hartley 2 (103P) traverses three constellations during September: Lacerta, Andromeda and Cassiopeia. Around the end of the month, scanning beneath the distinctive 'W' of Cassiopeia with your binoculars should bring the comet into view, it will probably be around +6 magnitude (but it may be much brighter, these things are impossible to predict).
- 08: New Moon
- 08: 30 minutes before sunrise watch Mercury rise directly beneath Regulus (alpha Leonis).
- 09: The Piscids meteor shower maximum.
- 11: Around 4pm see if you can spot the tiny sliver baby moon and Venus less than 2° away, in the blue sky! (A tip: you'll need to be looking south).
- 16: Estimated final launch of the Space Shuttle Discovery and the end of an era, as this is the last of the shuttle missions before the fleet is mothballed.
- 21: Jupiter at 'opposition' — this means it is the closest distance from Earth and therefore the best time to view it and its largest moons.
- 23: Autumnal Equinox (Northern Hemisphere)/Spring Equinox (Southern Hemisphere)
- 23: Full Moon (the Harvest Moon)
- 30: Comet Hartley 2 beneath Cassiopeia.
Chat about your celestial observances at the H2G2 Astronomy Society. Comment on anything in this edition of Babe Among the Stars by starting a new conversation below.