Edwin Hubble Redeemer Of Island Universes

''Whether true or false, the hypothesis of external galaxies is certainly a sublime and magnificent one. Instead of a single star system it presents us with thousands of them____Our conclusions in Science must be based on evidence, and not on sentiment. But we may express the hope that this sublime conception may stand the test of further examination.''

A C D Crommelin, 19171

On the evening of his eighth birthday, Saturday 20 November 1897, Edwin Powell Hubble looked forward eagerly to a special gift: he would be allowed to stay up late to look through his grandfather's telescope. Unlike Harlow Shapley, who, some 120 miles to the west in Nashville, Missouri, had just celebrated his 12th birthday, Hubble developed a fascination for astronomy as a young boy. His maternal grandfather, William James, introduced him to stargazing. James, a medical doctor and drugstore owner, had built his telescope himself.

The night of 20 November was evidently a clear one in Hubble's hometown of Marshfield, Missouri, for his sister later reported to his biographer that he had had a great time.2 We have no record of what objects grandfather James pointed the telescope to that night, but some at least are fairly good bets. At that time of year, and from that location, the Andromeda nebula would have been high overhead shortly after Hubble and his family finished dinner. Amid the stars of those constellations visible all night — including Andromeda, Ursa Major, Ursa Minor, Cepheus, and Taurus—James might have located double stars or individual stars famous for their particular characteristics. Mizar, the middle star of the three in the ''handle'' of the Big Dipper asterism of Ursa Major, for example, appears to be double upon close inspection. As seen through a small telescope, Mizar turns out to be not just a double, but a triple star system. In the constellation Cepheus, near Andromeda, James might have pointed out one of the reddest stars of the sky, a star Herschel had dubbed the ''garnet star.'' The Pleiades asterism would certainly have been on James's observing list, as his telescope, no matter how small, would have made the six naked-eye stars of the group multiply spectacularly to dozens.

Neptune rose in the east at about 7 p.m., although this dim planet would have been a challenge for James to find, unless he had detailed information about its location. At about 10 p.m., Orion rose, and no amateur astronomer would fail to put the famous nebula in Orion's sword on display. Then, if young Edwin was allowed to stay up really late, his grandfather may have shown him Jupiter and its four principal moons, first seen through a small telescope by Galileo. Jupiter rose above the horizon at about 3 a.m., followed the next hour by the waning Moon. Certainly Hubble and his grandfather saw many meteors, for Hubble's birthday fell near the peak of the Leonid meteor storm. Mars, a much-discussed planet at the time, was not visible that evening, having set before dark, along with Saturn and Venus.3

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