U.S. History-Great Astronomical Discoveries

Great Astronomical Discoveries

The series of articles present the astronomical discoveries made by the famous British astronomer , Sir John Herschel , by means of a telescope of enormous dimensions and an entirely new principle . The first of the series of articles describes in detail his invention of a special system which magnified so greatly that one could observe the moon 's surface as if one were standing on it . According to him , the telescope could see objects on the lunar surface as small as 18 inches across

Within two years of his father

's death John completed his new apparatus and adapted it to the old telescope with success that was close to perfection . As described in detail , the first in the series of articles mentions that John found that the magnifying power of 6 ,000 times when applied to the moon , which was the severest criterion that could be selected , produced , under these new reflectors , a focal object of exquisite distinctness , free from every achromatic obscurity , and containing the highest degree of light which the great speculum could collect from that luminary . The enlargement of the angle of vision which was thus acquired , is ascertained by dividing the moon 's distance from the observatory by the magnifying power of the instrument and the former being 240 ,000 miles , and the latter 6 ,000 times , leaves a quotient of 40 miles as the apparent distance of that planet from the eye of the observer . Later on it became well known that no terrestrial objects can be seen at a greater distance than this , with the naked eye even from the most favorable elevations . The rotundity of the earth prevents a more distant view than this with the most acute natural vision , and from the highest eminences and , generally , objects seen at this distance are themselves elevated on mountainous ridges . It is not pretended , moreover , that this forty miles telescopic view of the moon presented its objects with equal distinctness , though it did in equal size to those of this earth , so remotely stationed . The elder Herschel had nevertheless demonstrated that with a power of 1 ,000 times , he could discern objects in this satellite of not more than 122 yards in diameter . If therefore the full capability of the instrument had been elicited by the new apparatus of reflectors constructed by his son , it would follow , in mathematical ratio , that objects could be discerned of not more than 22 yards in diameter . Yet in either case they would be seen as mere feeble , shapeless points , with no greater conspicuity than they would exhibit upon earth to the unaided eye at the distance of forty miles

In a nutshell , Herschel had established a new theory of cometary phenomena , discovered planets in other solar systems and solved or corrected nearly every leading problem of mathematical astronomy . Then almost as though it were an afterthought , the articles reveal Herschel 's final achievement , which is the discovery of life on the moon

The succeeding articles...