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
Last month I mentioned the upcoming total lunar eclipse on 15 June. Unfortunately most of us in the UK were clouded out, but some lucky people were witness to it. There are many images uploaded to the photo sites and do check out the wonderful APOD photo. Luckily for those who missed it this time, there's another one coming along soon! The next total lunar eclipse is on 10 December, and people in North America, Europe, East Africa, Asia, Australia and some Pacific regions will be able to watch it (clouds permitting). When the Sun is shining on it during the night, the Moon looks like a bright flat disc to us denizens of Earth. For me, one of the best things about a lunar eclipse is that you get to see the Moon as it really is; that is, a sphere.
This month there are two new moons; this doesn't happen very often as the lunar cycle lasts roughly 29.5 days, so the first new moon would have to fall on the 1st day of the month to be in with a chance of squeezing another in. July's new moons fall on the 1st and the 30th.
There is a comet, which has been labelled C/2011 L4 (PANSTARRS1), currently positioned just beyond the orbit of Jupiter, heading our way. Astronomers think that the comet's path will take it to within 0.4 AU (about the same as Mercury's distance from the Sun). It is thought that the comet originated from the Oort Cloud: it is not a periodic (regular) comet like the famous one named after Halley. I imagine there was some kind of collision in the Oort Cloud and this particular 'dirty snowball' got a kick which sent it our way. It will take Comet C/2011 L4 (PANSTARRS) until 2013 to reach the inner Solar System (it may have been dubbed a more user-friendly name by then). As to when the comet will become a naked-eye viewing object remains anyone's guess. I'll try and keep you posted.
The comet has an orbit that is close to parabolic, meaning that this may be the first time it will ever come close to the sun, and that it may never return.
– Astronomer Richard Wainscoat of the University of Hawaii
Shooting Star Spotting
In July the main meteor shower is the Delta Aquarids, but historically it's not a great performance. A more likely event when you'll see at least some 'shooting stars' every few minutes (depending on the weather and viewing conditions) is next month when the main part of the Perseids' shower is due. The Perseid meteor shower actually commences as early as 23 July when you might see one shooting star each hour, slowly building up to five Perseids an hour by the end of the month. By 10 August the count could be ten per hour! The Perseid peak (has been known to be one-a-minute) is the main event of the year for some astronomers, who congregate at a dark sky viewing area with others of the same ilk, like the local astronomy club. I am a member of the Cleethorpes and District Astronomy Society and we have a 'Shooting Star Party' on Perseid Peak night at the home of one of the members who lives out in the country away from the glare of light pollution.
July 2011 Diary Dates
- 01: New Moon
- 03: Mercury 5° north of Moon
- 04: Brand new sliver moon hangs below Regulus (alpha Leonis)
- 07: The Moon, Saturn and Spica (alpha Virginis) form a triangle
- 15: Full Moon (the Buck Moon, the Hay Moon, the Crane Moon or the Summer Moon)
- 23: Perseid meteor shower begins
- 24 (morning): Jupiter 5° south of Moon
- 26: Moon positioned between 'Eye of the Bull' Aldebaran and The Pleiades star cluster in Taurus
- 28-9: Delta Aquarids meteor shower maximum
- 30: New Moon
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.