TIME AND SPACE

Greymouth Evening Star, 19 March 1934, Page 12

TIME AND SPACE

AN ASTRONOMER EXPLAINS.

Time —apparently relentless arbiter of human measurements and duration —is itself actually the plaything of planetary movements and positions, according to Dr Harlow Shapley, director of the Harvard College Observatory, who won the 1934 medal of the Royal Astronomical Society of England, states the “Christian Science Monitor.” “If the earth were moonless, kept the same face always towards the sun, as does Mercury, and had its polar axis perpendicular to its orbit, we would not have days, or months, or seasons, and we would be practically unconscious of years,” Dr Shapley asserted in the third annual James Aithur lecture at Gold Memorial Library, ,New York University. • Explaining that it is the rotation of the earth which dominates the terrestrial time concept, Dr Shapley declared that the fact that the globe spins on an axis conditions, not only the subdivisions of time, but also the flow of time and the complicated social and economic life that runs on daily schedule. Should the conditions of the earth be rearranged as he previously explained the philosophy of time would be unrecognisable, he added.

“The relativistic universe, our intuitive conception of time ,is purely a local affair,” he continued. “Time on Jupiter or on Arcturus or on the speeding galaxies would involve quite other dissections' of the space-time continuum, but in speaking of the lifetime of a galaxy, we agree to use our naive, local, intuitive time, and intrude our local units of days and years into the discussion of .galactic history.”

Readings ffom the Book of Stars as yet only partly deciphered—in light which is already inscribed —although waves that started on their way more than 1,000,000 years ago and are now within our own galactic system show that the universe is “lopsided,” with 50 per cent more galaxies on the north than on the south side, on which the earth is located, Dr Shapley said. “All that we shall ever know, or that our descendants will know during the next 2000 or 3000 years, concerning these millions of external galaxies is already written out in the light waves that are now within our own galactic system,” he declared. “With the Harvard telescopes, we shall make within the next year 1000 photographs of external galaxies, which are at distances of more than 1,000,000 light years; but those photographs will be made by the flux of energy—light—that is already far this side of oui’ nearest star. “It appears that our own galactic

system is a member of a small group, all members within 1,000,000 light years of our galactic centre. But the most important of the new results on meta-galactic structure is. the increasing evidence that there is a measureable density gradient in .this part of the universe—that is an indication that galaxies become more frequent in number as the survey goes, from the south side to the north side of our galactic system. “At a distance of some 70;000,000 light years the frequency is 50 per cent, higher in, the north than in the south; but Dr Edin P. Hubble’s recent ly published investigations show that the equality in density is restored at a distance of 200,000,000 light years. “This result seems to indicate a clustering of galaxies on a larger scale than heretofore recognised, but much further work will be necessary, and literally hundreds of thousands of new galaxies will be catalogued and studied before we can come to definite quantitative conclusions concerning the meta-galactic gradient.”