PLANETS IN MAY

Press, Volume CIV, Issue 30739, 1 May 1965, Page 7

PLANETS IN MAY

The planet Mercury Is making its best early-morn-ing appearance for this year. It is near the boundary between the constellations of Pisces the fishes and Cetus the whale—a region of the sky which is rather lacking in bright stars. This means that just before dawn Mercury is the brightest object to be found low in the rky in the direction between east and north-east. It is orange in colour and certainly appears to shine with more warmth than any stars in its vicinity. Although the temperature of any planet is not to be compared to that of a star, the planet Mercury is certainly the hottest planet in our solar system. And, strangely enough it is also the coldest. Such a strange state of affairs follows from the fact that Mercury keeps one side continually facing the sun, just as the moon keeps one side facing the earth. This boosts the temperature of the sunward side of Mercury to about 640 degrees Fahrenheit, hot enough to melt tin and lead. The dark side of Mercury is perpetually sunless and is too cold to be measurable—probably its temperature is about 20 degrees above absolute zero. Even the distant planet Pluto is not thought to be as cold as the dark side of Mercury. Mars and Saturn are the

Planet Visibility Table

only other planets to be seen this month. Jupiter and Venus are almost lost in the glow of evening twilight—perhaps someone with sharp eyes may glimpse Jupiter within the next few days, but it is rapidly approaching conjunction with the sun. Mars is lord of the evening sky at the moment. It is still quite bright and its reddish hue is plain. Just to the left of Mars is the star Regulus, brightest member of the constellation Leo the lion.

When Mars sets shortly after midnight it is the turn of Saturn to rise. By the time dawn is near Saturn is well up in the north-eastern sky. Do not confuse it with Mercury which, although of similar colour, is much lower in the sky about 6 a.m. On May 30 there will be a total eclipse of the sun, visible from the northern tip of the North Island. Plans for observing this eclipse have been under way for some time. Scientists from this province will play a prominent part in making observations: Mr F. M. Bateson, astronomer in charge at the Mount John Observatory, will lead an expedition to the Cook Islands to view the eclipse, and Dr. J. B. Gregory, of the University of Canterbury, will supervise rocket and radio observations from near Kaitaia.

May 2 May 16 May 30 Mercury rises . 5.06 a.m. 5.29 a.m. 6.37 a.m. Mars due north 8.38 p.m. 7.53 p.m. 7.13 p.m. Mars sets 2.03 a.m. 1.25 a.m. 12.53 a.m. Saturn rises 2.29 a.m. 1.39 a.m. 12.48 a.m. Jupiter sets 6.31 p.m. 5.47 p.m.