X-ray Source
An extended X-ray source centered at 1300+28 in the direction of the Coma cluster of galaxies was reported before August 1966. This X-ray observation was performed by balloon, but the source was not detected in the sounding rocket flight launched by the X-ray astronomy group at the Naval Research Laboratory on November 25, 1964. A strong X-ray source was observed by the X-ray observatory satellite Uhuru close to the center of the Coma cluster and this source was suggested be designated Coma X-1.
The Coma cluster contains about 800 galaxies within a 100 x 100 arc-min area of the celestial sphere. The source near the center at RA (1950) 12h56m ± 2m Dec 28°6' ± 12' has a luminosity Lx = 2.6 x 1044 ergs/s. As the source is extended, with a size of about 45', this argues against the possibility that a single galaxy is responsible for the emission. The Uhuru observations indicated a source strength of no greater than ~10−3 photons cm−2s−1keV−1 at 25 keV, which disagrees with the earlier observations claiming a source strength of ~10−2 photons cm−2s−1keV−1 at 25 keV, and a size of 5°.
Read more about this topic: Coma Cluster
Famous quotes containing the word source:
“Life has no other discipline to impose, if we would but realize it, than to accept life unquestioningly. Everything we shut our eyes to, everything we run away from, everything we deny, denigrate or despise, serves to defeat us in the end. What seems nasty, painful, evil, can become a source of beauty, joy and strength, if faced with an open mind. Every moment is a golden one for him who has the vision to recognize it as such.”
—Henry Miller (1891–1980)