Home Page Science Frontiers

No. 39: May-Jun 1985

Issue Contents

Other pages











Exorcising The Hidden Mass

These days the astronomical publications are full of discussions of the "missing mass" problem. It seems that for galax-ies to move the way they do, there has to be some "dark matter" out there, assuming Newton's Laws of Gravitation and Motion are valid. Something unseen is tugging on galaxies and the stars that comprise them.

This is a sad situation, according to Moto Milgrom, an Israeli astrophysicist. Maybe there is nothing hidden and Newton's Law of Gravitation is wrong. After all, it was derived solely on the basis of solar-system observations. On a larger scale, it might be incorrect. Milgrom offers a startling alternative: for accelerations greater than a, let Newton's Law be; below that value, let the square of the acceleration be proportional to the mass of the attracting body and the inverse square of the distance.

This done and presto the need for missing mass disappears. Even more remarkable is the fact that a particle with the acceleration a just reaches the speed of light over the age of the universe.

(Milgrom, Moto; "Newtonian Gravity Falls Down," New Scientist, p. 45, March 7, 1985.)

Comment. It would be more than passing strange for cosmic laws to suddenly shift gears so radically at a specific value of acceleration.

Reference. The "missing mass" problem is covered in depth in AWB5 and other entries in Stars, Galaxies, Cosmos. For more on this Catalog volume, visit: here.

From Science Frontiers #39, MAY-JUN 1985. 1985-2000 William R. Corliss