Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2002 October 7
See Explanation.  Clicking on the picture will download
 the highest resolution version available.

The Galaxy and the Quasar
Credit: R. Knacke (Penn State Erie) et al., Hubble Heritage Team, NASA

Explanation: Is the galaxy in the center connected to the quasar on the upper right? Disagreements about systems like this have raged for decades and have been used to challenge the foundations of modern cosmology. Some believe that the quasar Markarian 205 was recently ejected from galaxy NGC 4319, indicating that the high redshift of Markarian 205 is not indicative of its distance. Most astronomers have come to believe, however, that the two are not physically associated, and that the high redshift of Markarian 205 indeed indicates that it lies across our universe. In this predominant view, as with a tree branch that happens to point toward the Moon, their juxtaposition in the above image is just coincidence.

Tomorrow's picture: Black Hole Jets

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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
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& Michigan Tech. U.