EARTH'S SPEED

Evening Post, Volume CIX, Issue 38, 14 February 1930, Page 5

EARTH'S SPEED

FOUR SEPARATE MOTIONS

711,000 MILES EVERY HOUR

One- of astronomy's latest discoveries indicating the world is travelling more than 2000 times as fast as the Schneider Cup record in a vast/ whirl including the sun and all stars visible to the eye, was reported to the American -Association for the Advancement of Science, says an American writer. Existence of such motion long has been believed in by many astronomersand the discovery described to-day is speed measurements and verification of the whirl. It is the rotation about a huge, massive centre not only of the visible stars but of everything for many billions of miles beyond them.

It is the formation of stars in the shape of an immense flattened ball, whirling with their centre in the direction of the constellation Sagitarius, a centre so distant that its light takes about 47,000 .years to reach us.

STUDIED MOVEMENT 6 YEARS,

The findings were presented before the astronomical section at Drake University by Dr. J. S. Plaskett, 'F.R.S., director of the Dominion Astrophysical Observatory at Victoria. B.C. They were obtained in six years' study with the second largest telescope in the world by Dr. Plaskett and his assistant, Dr. J. A. Pearcc. The speeds of a jazz age pale alongside the dizzy celestial gaits, revealed. For they give the earth four separate and simultaneous motions. There is the daily revolution on its axis, about 28,000 miles in 24 hours; the yearly trip around the sun at a speed of about 18* miles a second, or roughly 1200 times that of an express train; a "random ""motion in which the earth is moving along with the sun in a journey not seemingly in the direct patch of the great whirl, and finally the high speed spin of the entire near-by section of the universe.

So vast is this whirl that Dr. Plaskett estimated about 300,000,000 years are required for one rotation about the centre. .

SPEEDS 200 MILES A SECOND,

"The first point shown quite distinctly by this work," he said, "is the rotation of the whole galactic system at a speed of about 300 kilometres a second, or around 200 miles, which would be more than 2000 times the speed of the present Schneider Cup record."

That record is 355.S miles an hour, man's fastest. The speed of the galactic system is more than 711,000 miles an hour.

The evidence on this rotation was found while checking something supposed to be "errors." These were certain puzzling phenomena in speetroscopic records of starlight, which Dr. Plaske-tt siad astronomers for twenty years usually have regarded as due to errors in instruments and possibly partly due to an Einstein shift effect. They went by the name of the "X component," and were indications of star motion not well accounted for. Dr. Plaskett studied this speed in 810 B-type stars. These are the hottest of stars, some of them, he said, 1000 times as bright as the sun. All are thought to belong to the same star family as the sun, and all are within .about 3000 light years from earth. That makes them just a respectable sized bit of the greater star system in which Dr. Plaskett 'a researches show them as part of the general whirl. The second important result of the investigation, ho said, gets rid of the X component of error. Part of it disappeared in the general rotation findings. The rest of it, he found, indicated that .certain of these B stars, the brightest of them, all in the southern sky, are speeding away from the earth and sun at rates averaging from six to ten kilometres a second. _ _ There are "random" speeds, indications apparently of some not fully understood motions. Dr. Plaslcott suggested that these motions may be an indication that parts of the universe arc new enough so that hey have not yet entirely settled down.