Philips Atlas of the Universe

Millennium Comets

T

he closing years of the old century were graced by two

bright comets. The first of these was discovered on 30

January 1996 by the Japanese amateur Yuji Hyakutake,

using 25 
150 binoculars; it was then of the 11th mag-

nitude. It brightened steadily, and moved north in the

sky; it reached perihelion on 1 May 1996, at 34 million

kilometres (21 million miles) from the Sun. On 24 March

it had passed Earth at 15 million kilometres (9,300,000

miles) – 40 times as far away as the Moon. At this time

it was near Polaris in the sky; the magnitude was 1,

and there was a long, gossamer-like tail extending for

100 degrees. The main feature of the comet was its beauti-

ful green colour. It faded quickly during April; its period

is around 15,000 years. In fact it was a small comet, with

a nucleus estimated to be no more than 3.2 kilometres

(2 miles) in diameter.

The second bright comet was discovered on 22 July

1995 independently by two American observers, Alan

ATLAS OF THE UNIVERSE

▲ Comet Hyakutake,

photographed in 1996 by

Akira Fujii. Note the

lovely green colour of the

comet in this photograph.

 Comet Hale–Bopp,

photographed by Akira Fujii

on 10 March 1997. Note the

clear separation of the long

blue ion tail and the dust tail.

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