STUDYING THE STARS.

Evening Star, Issue 11452, 21 January 1901, Page 8

STUDYING THE STARS.

Sir Robert Ball, in the early chapters of his famous 'Story of the Heavens' (now being issued in monthly parts), tells ns how much the beginner in astronomy may observe for himself. Let us suppose (he says) that the observer is provided with an opera-glass and is abont to commence his astronomical studies. The first step is to become acquainted with the conspicuous group of seven stars called the Plough, or Charles's Wain, but astronomers prefer to regard it as a portion of the constellation of the Great Bear (Ursa Major). There are many features of interest in this constellation, and the beginner should learn as soon as possible to indentify the seven stars wbioh compose it. Of these the two at tho head of the Bear are generally called the "pointers." They are of special use, because they serve to guide the eye to that most important star iu tlwwhole sky, known as the Pole Scar. Fix tho attention on that region in tho Gn 1 Bear which forms a sort of rectangle Thenext fine night try to count how mmy iiurs aro withiu that rectangle. O-t a very flao night, without a moou, perhaps aua,«u might be perceived, or even more, according to tLo keenness of tho eyesight. But when the opera glass is directed to tho same piri of the constellation an astonishing sight is witnessed. A hundred ttara can now b,i ttcto with the greatest f as*.. But tho opemgU&B will not show nearly a"! the stars in thiß region. Any good telescope will reveal nwny hundreds too faint far the feebler instrument. The greater the telescope the moro numerous tho stars ; so that seen through one of the colossal instruments the somber would have ta be reckoned in thousands. We have chosen the Great Bear because it ia more generally known than any other constellation. But the Great Bear is not exceptionally rich in stars. To tell the number of the atari is a task which no man

haa accomplished, but various estimates have been made. Our great telesoopea can probably Bhow at least 50,000,000 stars.