The comet is here!

Waimarino Bulletin, Volume 3, Issue 38, 4 March 1986, Page 14

The comet is here!

Halley's Comet is now moving away from the sun after its closest approach on 10 February and is rapidly moving down into the southerh hemisphere sky. It will be rising in the east about 2.50am on 5 March, 1.30am on 15 March and 10.10pm on 30 March, its tail visible low in the sky. However, about two hours later than those times the comet will be 20 degrees higher above the eastern horizon and well placed for observation. The best period to view the comet this month will be between 10 and 23 March at about 3.00 or 4.00am. Early April will provide the best views when it will be visible during the entire night and virtually overhead at dawn. Waimarino residents

should have good views of the comet providing the sky is clear. The Carter Observatory in Wellington recommends city dwellers take a trip to the country away from street lights. For this area just turn off the house lights and go outside! The core or nucleus of Halley's Comet is thought to be made of water ice contaminated with dust. The nucleus is between three and eight kms across. As the comet approaches the sun its warmth causes evaporation, and dust grains are released forming a cloud around the nucleus which may be 100,000 kms across. The sun boils off a million tonnes of material daily which moves into space at thousands of kms per second. This is the solar wind which blows back gas and dust to form the comet 's tail.