NGC 6643

Also Known as:

Object Type: Spiral Galaxy

Constellation: Draco

Distance from Earth: 78 million light years

Apparent Magnitude: 11.7

Coordinates: RA 18H 19M 46.41 Sec DEC 74 deg 34 min 06.10 sec

Actual Size: 86,300 light years

Apparent Dimensions: 3.32 arcminutes x 1.63 arcminutes (NGC3613)

Discovered by: NGC 6643 was discovered by Eduard Sch�nfeld in 1858. The exact date is unknown.
Horace Tuttle then discovered it independently on September 1, 1859.

Description: NGC 6643 is a Spiral Galaxy in the constellation of Draco.
It has a very small nucleus separated from the broken remnants of an inner ring that extends into a complex, irregular spiral pattern.
Bright knots that are probably H-II regions outline the multiple spiral arms.
It is a very blue spiral classed as SA(rs)c by NED. The blue color indicates much of its light comes from newly minted massive blue stars.
Notes at NED indicate there are extensive H alpha regions outlining the spiral arms.
Though the blue star clusters forming in them do show as blue knots that give the galaxy most of its spiral structure.
Except for the odd rather straight arm to the southwest, its spiral arms are rather weak being overpowered by the star clusters along the arms.
What triggered this massive star formation apparently isn't known.

Click Below Image(s) for Full Size:

NGC 6643 is a Spiral Galaxy in the Draco constellation. NGC 6643 is situated close to the northern celestial pole and, as such, it is visible for most part of the year from the northern hemisphere.
Given its magnitdue, NGC 6643 is visible with the help of a telescope having an aperture of 8 inches (200mm) or more.
It s classification is A(rs)c II Spiral, Mixed Inner Ring - S-shaped, Luminosity Class II

Platesolve

NGC 6643 Galaxy

NGC 6643 Galaxy closeup

Imaging Details
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