What is so interesting about the galaxy Dwingeloo 1?
In 1994, a team of astronomers from the United States, Great Britain and the
Netherlands discovered this galaxy while continuing a multi-year, systematic
survey for galaxies obscured by the Milky Way. The Dwingeloo radio
observatory is a 25-meter telescope built in 1957 to study hydrogen gas
emission at 21 centimeters wavelength. In the November 3, 1994 issue of
Nature, they announced the discovery of a faint galaxy they called
'Dwingeloo 1'. This galaxy, located at RA(1950) = 2h 52m 50s and
dec(1950) = 58d 42' is only 2 degrees away from a previously-discovered nearby
galaxy called Maffei 2, which was discovered in the infrared over 25 years
ago.
Dwingeloo 1 can be seen on a Palomar Observatory Sky Photograph as a faint
fuzzy patch of light about 4.2' arcminutes across. A detailed optical
study reveals that this is a 'barred spiral' galaxy of class SBb. The
hydrogen gas observations by the Dwingeloo telescope indicate a mass of about
45 million solar masses; only 3-times less than that of the Milky Way.
It is located about 3 million parsecs or 10 million light years from the Milky
Way, and is dynamically associated with a small sub-group of galaxies
not related to the Local Group. This new group
contains Maffei 2, Maffei 1 and IC342, along with possibly a dozen other
'dwarf' galaxies yet to be detected.
The above photo is by S. Hughes & S. Maddox (IoA, Cambridge) et al., Isaac Newton Telescope
Copyright 1997 Dr. Sten Odenwald
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