User:Osiris333/Tom Van Flandern

Tom Van Flandern is an American astronomer. He is known primarily for advocating the Exploded Planet Hypothesis, which argues that an exploded planet in the Bode orbit between Mars and Jupiter is responsible for the orgin of almost all known comets and meteors, as well as the asteroid belt. Van Flandern is also known as a critic of the Big Bang theory, especially the concept of an expanding universe, and for advocating a non-standard cosmology incorporating intrinsic redshift, as advocated by Halton Arp.

Career
Arp was born March 21 1927 in New York City. His bachelor's degree was awarded by Harvard (1949), and his Ph.D. from Caltech (1953). Afterwards he became a Fellow of the Carnegie Institution of Washington in 1953, performing research at the Mount Wilson Observatory and Palomar Observatory. Arp became a Research Assistant at Indiana University in 1955 and subsequently in 1957 became a staff member at Palomar Observatory, where he worked for 29 years. In 1983 he joined the staff of the Max Planck Institute for Astrophysics in Germany.

Quasars and redshifts
Arp's hypothesis is that quasars or quasi-stellar objects (QSOs) are local objects ejected from the core of active galactic nuclei (AGN). The theory was originally proposed in the 1960s as an alternative to Maarten Schmidt's explanation for QSOs, which stated that they were very distant galaxies that appeared to be highly redshifted because of the expansion of the universe. Arp argues that in some photographs a QSO is in the foreground of (or otherwise connected to) galaxies that according to the Hubble's law interpretation of redshift are significantly closer to earth than the QSO. He also claims that quasars are not evenly spread over the sky but tend to be more commonly found in positions of small angular separation from certain galaxies. The implication of the hypothesis of local QSOs is that most of the observed redshift of these QSOs must have a non-cosmological or "intrinsic" origin. Arp has suggested that the QSO emission may instead be ejecta from active galactic nuclei. Nearby galaxies with both strong radio emission and peculiar morphologies, particularly M87 and Centaurus A, appeared to support Arp's hypothesis. In his books, Arp has provided his reasons for believing that the Big Bang theory itself is wrong, citing his research into QSOs. Instead, Arp supports the redshift quantization theory as an explanation of the redshifts of galaxies.

Critics
Since Arp originally proposed his theories in the 1960s, however, telescopes and astronomical instrumentation have advanced greatly; the Hubble Space Telescope was launched, multiple 8-10 meter telescopes (such as those at Keck Observatory) have become operational, and detectors such as CCDs are now more widely employed. These new telescopes and new instrumentation have been utilized to examine QSOs further. QSOs are now generally accepted to be very distant galaxies with high redshifts. Moreover, many imaging surveys, most notably the Hubble Deep Field, have found many high-redshift objects that are not QSOs but that appear to be normal galaxies like those found nearby. Moreover, the spectra of the high-redshift galaxies, as seen from X-ray to radio wavelengths, match the spectra of nearby galaxies (particularly galaxies with high levels of star formation activity but also galaxies with normal or extinguished star formation activity) when corrected for redshift effects.

Nonetheless, Arp has not wavered from his stand against the Big Bang and still publishes articles stating his contrary view in both popular and scientific literature, frequently collaborating with Geoffrey Burbidge and Margaret Burbidge.

The Atlas of Peculiar Galaxies
Arp has compiled a catalog of unusual galaxies titled Atlas of Peculiar Galaxies, which was first published in 1966. Arp realized that astronomers understood little about how galaxies change over time, which led him to work on this project. This atlas was intended to provide images that would give astronomers data from which they could study the evolution of galaxies. Arp later used the atlas as evidence in his debate on QSOs.

Astronomers today recognize that Arp developed an excellent atlas of interacting and merging galaxies. Many objects in the atlas are primarily referred to by their Arp number. Many of these objects (particularly Arp 220) are also used as spectral templates for studying high-redshift galaxies.

Notable Honors and Awards
In 1960, Arp was awarded the Helen B. Warner Prize for Astronomy by the American Astronomical Society, a prize "normally awarded annually for a significant contribution to observational or theoretical astronomy during the five years preceding the award."

In the same year, Arp was awarded the Newcomb Cleveland Prize for his address, "The Stellar Content of Galaxies" read before a joint session of the American Astronomical Society and AAAS Section D.

In 1984, he was awarded the Alexander von Humboldt Senior Scientist Award.