Aug. 5, 1962: First Quasar Discovered

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1962: A nearly botched observation of a distant radio source leads to the identification of the first-known quasi-stellar astronomical object, or quasar.
Until the development of radio astronomy in the 1940s, our knowledge of the universe outside our own solar system was pretty much restricted to objects that emitted light in or near the visible spectrum. Then, astronomers began discovering objects that emitted radio waves. Excitement.
They also found some points in the distant skies that emitted both visible light and radio frequencies. Big excitement.
Astronomers Allan Sandage and Thomas Matthews were looking around in 1960 when they discovered a blue star-like object that sends out particularly intense radio waves. Big mystery.
British radio astronomer Cyril Hazard applied his method of observation to the growing puzzle in 1962. The technique, lunar occultation, used the well-calculated orbital path of the moon to mark exactly where an object is when the moon passes in front of it, blocking the emissions, and again where it is when the radio signal re-emerges as the moon moves out of the way.
Hazard was then at the University of Sydney and booked observation time on the 210-foot Parkes Radio Telescope a few hundred miles inland. Hazard was apparently better at astronomy than getting around on land. The night he was supposed to observe the powerful radio source in Virgo, he took the wrong train in New South Wales and missed the whole show.
Good luck for him, science is a social endeavor (or endeavour in Australia). Observatory director John Bolton and his staff took over. But the radio source in question was low on the horizon, so they cut down some trees and even removed the giant radio telescope's safety bolts. Only then could they tilt the dish low enough to make the observation. Kluge city.
The object of their attraction, 3C 273, was emitting a huge amount of energy, with a very unusual -- and never-before-seen -- spectrum. Bigger mystery.
Maarten Schmidt used the Hale optical telescope at California's Mount Palomar observatory to puzzle it all out the following year. He saw a visible jet rising from the optically faint object. Like a hydrogen jet.
When Schmidt analyzed the spectrum's strange, wide emission lines, he realized they were hydrogen lines shifted an astonishing
16 percent toward the red -- which is why they hadn't been recognized earlier. But a red shift of that magnitude meant the object was moving away from Earth at almost 30,000 miles per second (one-sixth the speed of light) and was 3 billion light-years away. It was farther away and brighter than most known galaxies.
Astronomers soon were calling this new class of objects -- of which 3C 273 is the granddaddy and archetype -- quasi-stellar radio sources. A NASA scientist trimmed that to quasars. Today they're called
quasi-stellar objects, or QSOs, because not all of them emit radio waves.
After nearly half a century of research,
new discoveries about quasars seem to raise new questions even as they answer the old ones.