The Birmingham age-herald., 1918-07-28

variation in brightness will, of course,
 be kept under careful observation, the more so as this will probably fIuctuate
 Thus the brightness of the new star of 1901, while this was fading away. os-
 eillated more than a whole magnitude
 the period between its greatest bright ness varying from about two days at first to six or eight days when 1t was
 becoming invisible to the naked eye. Sec
 ond, the lines of the spectrum will be
 very carefully studied, for very remark
 able changes always occur in the spectra
 of new stars. The spectrum some-
 times changes in character from
 that of a star to that of nebula, and somethimes Gas in the new star in
 Auriga 1t changes back to the spectrirn of star again. No satisfactory ex-
 planation of these renarkable changes
 has as yet been found i.3 Lastly, the position of the new star
 will be determined with the highest pos sible accuracy in order that it's "paral-, lax" or displacement on the sky. ow- ing to our passage about the sun, may
 be determined From this the distance
 of the star will become known, but it will require many months of most ac-
 curate observation to determine this dis
 tance. It is not until the absolute dis tance away has been found that the brightness of the new star compared with that of our sun can be determined. Thus, no definite displacement could be found for the las6 bright new star, that Tn
 Perseus; but it Is believed to have been so far away that it's light required about
 300 years to come to us. If this is true,
 then when brightest the star emitted more than 5000 times as much light as our sun. If the last new star is so far away as this. it at one time emitted at least 320Oo times as much light as our sun. Yet in a few short weeks this great outburst of light almost ceases. Truly the new stars are among the most puz- zling of all astronomical objects.
 PLANETS IN AUGUST
 Mercury will reach it's greatest dis tance east of the sun on August 5, and during the first days of the month l it may be seen shining in the twilight ] glow almost due west for about one \ hour after sunset. It will enter the 1 morning sky on September l.
 l Venus is conspicuous in the morning
 heavens. rising far in the northeast more than 2k hours before sunrise on August 1; but this time is diminished to l less than two hours by August S1. It is now 50 times as bright as a first , ma gnitude star, and in the telescope has the shape of the moon when about three e-quarters full. It is continually drawing nearer the suns rays though it will not pass that body and enter
 the evening sky until November 23. Mrs will pass out of the constella-
 tion Virgo and into the borders of
 Libra during the month. On August 4 it will pass north of the bright star Spica Cat A. Figure D. and at this
 time the two objects can be. seen to- gether in the telescope. the bluish color
 of the star appearing in striking con-
 trast to the redness- of the planet Sim. ilarly on September Mars will pass even nearer the widely double yellow ish star at B " 9
 Jupiter is now east of the planet Venus, and the two objects shine out brightly in the morning sky. Jupiter is. however, daily coming into more favorable position for observation, while Venus is constantly drawing
 nearer to the suns rays. On August Venus is but 20 minutes east of Jupi- ter, while on August 31 it Is more than one hour. or IS degrees. away As with Mars, the present is very fav- orable time to study the motions of these bright planets among the stars.
 Saturn enters the morning sky on August II, but toward the end of the month it is sufficiently far from the suns rays to be we'll observed. striking conjunction of Venus and Sa- turn will occur on September 4, when the former planet will pass so close to the latter that the objects will seem almost to touch each other as viewed with the naked eye, Unfortunatcly, this nearest approach will occur at 10 p. m (eastern time), and when they rise the next morning they will appear separated by distance equal to about
 half the diameter of the full moon. The two bright planets will. however, still afford beautiful sight in a small telescope The rings of Saturn are now well opened out. and the greenish color of this planet will be seen in strong contrast to the silvery Venus. Venus will appear far brighter than
 the larger but more distant planet, The latter is of about the zeroth magni- tude-that is, about two and one-half times as bright as a standard first