Tikalon Header Blog Logo

Most Distant Quasar

March 1, 2021

The universe is a large place. As astronomers have been able to examine its contained objects more closely with improved imaging technologies, some of the discovered objects are so strange that they took a long time to explain. One such object is the quasar, a contraction of the term, "quasi-stellar object," so-called because these had features, such as compactness, similar to stars, and other properties, such as luminosity, quite unlike stars. The five year old daughter of husband and wife astronomers and quasar observers, Margaret Burbidge (1919-2020) and Geoffrey Burbidge (1925-2010), is said to have called these objects of her parents' studies, crazy stellar objects, which is an apt naming.[1]

Margaret Burbidge receiving the 1983 National Medal of Science from US President, Ronald Reagan.

Margaret Burbidge receiving the 1983 National Medal of Science from US President, Ronald Reagan.

Burbidge is best known as an author of the 108 page "B2FH paper" in Reviews of Modern Physics, named after its authors, the two Burbidges, William A. Fowler (1911-1995), and Fred Hoyle (1915-2001).[2]

In 1976, Burbidge became the first female president of the American Astronomical Society. That was after her 1971 refusal of its Annie Jump Cannon Award, an award designated for women astronomers. Said Burbidge, "It is high time that discrimination in favor of, as well as against, women in professional life be removed."

(US government image, captured from a YouTube Video by the Women's Museum of California.[3] Click for larger image.)

Quasars were first detected by radio astronomers shortly after radio astronomy became an established scientific discipline enabled by advancements in microwave radar during World War II. Radio astronomers detected a few objects emitting large amounts of radio energy that did not seem to be matched with an optical image. This was not surprising at first, since the pointing accuracy of early radio telescopes was not that good. In some cases, a match was found with a point-like object that resembled a distant star.

Finally, in 1963, Allan Sandage (1926-2010), a pioneer in optical imaging of distant galaxies, and his colleagues matched a faint blue star with one such radio source, 3C 48. The optical spectrum, which at first resisted interpretation, turned out to be the highly redshifted spectrum of hydrogen. This led to the further problem that the large distance associated with this, and similar, objects, as calculated from the cosmological redshift, made them much more luminous than any galaxy. Furthermore, they were found to be more compact than galaxies, since their brightness varied on yearly timescales. This meant that their light came from a region less than about a light year in size. Our own Milky Way galaxy is about 185,000 light years in diameter.

The redshifted spectrum could not be denied, but there were immediate suggestions that, since the luminosity was so intense, that the redshift was not cosmological, possibly arising from light emission from a deep gravitational well, so these objects were closer. It was also suggested that the energy might derive from antimatter annihilation, the emission was from the white hole end of a wormhole, or a cascade of supernovae in which each explosion triggers others.

Figure caption

The Crab Nebula, a spectacular remnant of a supernova explosion.

The energy of such an explosion can exceed 1044 joules, which is why they were considered