Caldwell 44

Common Name: Propeller Galaxy

Also Known as: NGC 7479

Object Type: Barred Spiral Galaxy

Constellation: : Pegasus

Distance from Earth: 105 million light years

Apparent Magnitude: 11.6

Coordinates: RA 23H 04M 56.6S DEC 12 deg 19 min 22 sec

Actual Size: 100,000 light years in diameter.

Apparent Dimensions: 4.1 arc-minutes x 3.1 arc-minutes

Discovered by: NGC 7479 was discovered by William Herschel in 1784.

Description: NGC 7479 is a classical barred spiral galaxy.
The orientation of the galaxy is almost face on making it one of the best barred spirals to observe from the northern hemisphere.
Sometimes known as the Propeller galaxy it does however have some rather unusual features in that one of the spiral arms is much more prominent than the other. This may have been the result of a merger with a smaller companion about 300 million years ago. The bar is also unusually long.
NGC 7479 is also recognized as a Seyfert galaxy and a LINER undergoing starburst activity not only on the nucleus and the outer arms, but also across the bar of the galaxy, where most of the stars were formed in the last 100 million years. Studies of this galaxy indicate that it recently underwent a minor merger. This feature, along with the asymmetrical arms of the galaxy and the intense star formation activity are attributed to a merger with a smaller galaxy.
NGC 7479 does however have some rather unusual features in that one of the spiral arms is much more prominent than the other.
The spiral structure is also unusual in that the arms when observed in the radio spectrum appear to rotate in the opposite direction to those in the visible and near IR.
This may have been the result of a merger with a smaller companion about 300 million years ago.
NGC 7479 is also unusual in that it is extremely isolated. Often starburst galaxies occur because the galaxies have been stirred up by close encounters with other galaxies but that appears not to be the case here.
NGC 7479 appears to be at a distance of perhaps 105 million light years and may be associated with the Pegasus galaxy cloud.
This galaxy is similar in both size and morphology to the barred spiral NGC 1300. The bar is also unusually long.
The Propeller galaxy is an interesting subject for several other reasons as well. Hidden within the galaxy’s core lurks a supermassive black hole that feeds on large quantities of gas.

Click Below Image(s) for Full Size:

Visually the galaxy has been picked up as a faint smudge in telescopes as small as 4" but it will take much a much larger telescope to show the spiral structure.
The bar is relatively easy to see as in one of the spiral arms. The other is much more difficult.
The visibility of the arms depends very much on the transparency as well as the size of telescope.

NGC 7479 is best viewed in the summer months.

Platesolve

NGC 7479 Galaxy

Imaging Details
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