The Family Astronomy Club met tonight with the subject of tonight’s meeting being Comets. Another enthusiastic turn out of students and family members heard first from Miss Ellender who talked through what comets are and where they come from.
Comets have featured in a number of very familiar pieces of artwork almost all of which, it would seem, feature a representation of possibly the most renowned comet of all, Halley’s Comet. Featuring in a depiction of the Christmas nativity, the Bayeux Tapestry and many more. Comet Halley is a short period comet which has come from the Kuiper belt, “short period” as it’s orbit around our Sun takes just 75-76 years, the definition of short period being less than 200 years. Comets of longer period originate from the more distant Oort cloud more than a thousand times as far out.
Next year 12 student Vaughan Bryan gave a presentation on the ESA mission Rosetta, a mission which later this month hopes to actually land on a comet so we can learn more about these so called dirty snowballs. The Rosetta mission launched some 10 years ago and has been building up speed in order to catch up with Comet 67P/Churyumov–Gerasimenko. On November the 12th it is hoped that Rosetta’s lander, Philae will make a successful touchdown on the surface.
Members were lucky to have a break in the clouds so Mr Perkins trained our 16inch telescope on the Moon, in particular the Tycho crater. Named after the Danish astronomer Tycho Brahe, Tycho is one of the most recognisable craters on the Moon. It has a distinctive formation of rays leading away from it and has a large albedo in the middle which looks rather like a pimple and is formed in much the same way as water spits back up when a stone is dropped in a puddle or pool of water.
Finally to finish off Miss Ellender and Miss Harrington did some cosmic cooking and showed members what a comet is made of by making not one but two. Consisting mostly of frozen water, they added the ingredients, liberal amounts of dry ice and stirring until frozen. The result is a dirty snowball out gassing vapour just like the real thing.
The next Family Astronomy Club meeting is on December the 16th at the usual time of 6pm and will be our Christmas Special. For students (and their families) wishing to attend please see Miss Ellender, Miss Harrington or pick up a letter from student services.
The Malcolm Parry Observatory 