A Farther-Out Quasar

Although some 200 quasars (quasi-stellar sources) have been discovered since the first one was identified in 1960, scientists have been unable to agree on the nature, or even the size or distance of the mysterious starlike objects. Quasar controversies have so rocked the once stable world of astronomy that California Institute of Technology Astronomer Jesse Greenstein has been driven to poetic expression:

Horrid quasar Near or far, This truth to you I must confess; My heart for you is full of hate O super star, Imploded gas, Exploded trash, You glowing speck upon a plate. Of Einstein's world you've made a mess!

To make matters even messier, astronomers have now discovered a new quasar that is apparently farther, brighter and more enigmatic than any other yet found. Designated 0237-23, it was first detected and pinpointed by Astronomer John Bolton with the 210-ft. radio telescope at the Parkes Observatory in Australia. Using coordinates supplied by Bolton, California Astronomers Halton Arp and Thomas D. Kinman zeroed in on the quasar with the 200-in. optical telescope at Mount Palomar and the 120-in. Lick Observatory telescope.

153,000 Miles per Second. Jointly publishing their findings in the Astrophysical Journal, the three astronomers report that the wave length of light emitted from 0237-23 is more than double what it would normally be; it is shifted toward the red, or longer-wave-length end of the spectrum, by a factor of 2.22. Just as the lowered pitch of the whistle of a receding train is determined by the speed at which it is traveling, 0237-23's red shift--the largest ever observed in a celestial body--indicates to most scientists that the quasar is receding from the earth at 153,000 miles per second. Because the speed of recession of stars and galaxies is thought to be caused by the expansion of the universe and is generally believed to be a measure of their distance from the earth, 0237-23 may be farther away than any other known object. And because it can be seen so clearly in large telescopes despite its great distance, it may also be the brightest known object in the universe.

Unlike the spectra of other quasars, which demonstrate one red shift in their emission lines and sometimes another in their absorption lines (caused by the passage of their light through cooler matter on the way to the observer), the spectrum of 0237-23 displays three red shifts. In addition to the expected shift of its emission lines, Astronomers Greenstein and Maarten Schmidt (TIME cover, March 11, 1966) have found its absorption lines have two distinctly different and lower red shifts. Astronomer Greenstein believes that they are caused by light from the central body passing through two shells of gas rapidly expanding away from the quasar; the light is thus absorbed by matter that is receding from the earth at velocities slightly different from that of the central body.

Bright Core. There are other unusual features of 0237-23. The spectra of most quasars show the presence of only lighter elements, such as hydrogen, helium and silicon. The spectrum of 0237-23 shows that the expanding gas shells contain titanium and probably chromium, nickel, cobalt and iron--heavy elements never before detected in quasars.

Although clues provided by 0237-23 may some day fit into a pattern, they have so far only added to the confusion about quasars. Recent radio astronomy measurements indicate that some may be less than a light year (about six trillion miles) in diameter, mere specks in comparison with average galaxies, which contain billions of stars and are 100,000 light-years in diameter. And a new Caltech study suggests that quasars have an immensely bright core which is only a few "light days" in diameter. Yet if the quasars are as far out in space as their red shifts seem to indicate, they must emit 100 times as much light as an entire galaxy in order to appear as bright and distinct as they do.

Astronomer Schmidt believes that, on the basis of their red shifts, quasars are the most distant objects in the universe, but cannot satisfactorily explain how they generate their tremendous energy. Dr. Arp believes that quasars seem bright because they are relatively close and actually are objects expelled from galaxies wracked by explosions, but cannot satisfactorily explain their tremendous red shift. Says Schmidt: "If you get an impression of uncertainty about the state of knowledge of quasars, you are right. That is what the situation is."

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