Total eclipse of the Moon soon

Press, Volume CXI, Issue 32803, 31 December 1971, Page 17

Total eclipse of the Moon soon

There will be a total eclipse of the Moon on January 30.

The penumbral phase begins at 8.02. p.m., but this will have little interest until 9.12 p.m. when the Moon first moves into the umbra, or Earth’s real shadow. Then a slight indentation on the lunar limb will be noticed which steadily enlarges until the total phase starts at 10.36 p.m. Totality is short and ends at 11.12 p.m. The Moon leaves the umbra finally at 0.36 a.m. on January 31. During totality, the Moon does not become invisible because a,certain amount of light is refracted into the Earth’s shadow and this lights up the Moon. Whether an eclipse is bright or dark

depends on the amount of light that reaches the Moon. If the Earth is shrouded by dense dust clouds, such as! occur during volcanic eruptions, less light reaches the Moon and the eclipse is a dark one. More often the eclipsed Moon has a dull coppery hue. The annular eclipse of the Sun on January 16 will not be visible from our latitudes. It will be seen best from Antarctica across which the eclipse cuts a narrow path. The bright planets are not particularly Well placed this month. Venus, in the western evening sky, will be most conspicuous on account of its brightness. It cannot be mistaken for a star and several readers have reported sighting it in daylight. Venus sets about 10.05 p.m. on January 1; at 9.50 p.m. on January 15 and at 9.40 p.m. on January 31. Other planets in the evening sky are Mars and Saturn. The former, in the constellation Pisces, has grown much fainter as it recedes from the Earth. It is no longer worth the trouble of looking at, although it is the centre of much interest through the observations from the space probes now circling the planet. Saturn, in Taurus, is unfortunately rather far north for the best viewing. Nevertheless it is rewarding to observe it through a telescope as the famous ring system is wide open and can be seen to the best advantage. Saturn sets at 2.35 a.m. on January 1, at 1.30 a.m. on January 15 and at 0.30 a.m. on January 31. Mercury and Jupiter are in the morning sky. Mercury reaches its greatest elongation west of the Sun on January 1, but will only be visible in the dawn sky and therefore difficult to see. Jupiter emerges from conjunction with the Sun, rising at 3.40 a.m. on January 1, at 3 a.m. on January 15 and at 2.15 a.m. on January 31. For most of January it can only be observed, in pur) latitudes, against the bright; dawn sky. i