NGC 6946
Spiral Galaxy
NGC 6946 (= H IV.76), type Sc,
in Cepheus
Right Ascension |
20 : 34.8 (h:m)
|
Declination |
+60 : 09 (deg:m)
|
Distance |
10,000 (kly)
|
Visual Brightness |
8.9 (mag)
|
Apparent Dimension |
11 x 10 (arc min) |
Discovered by William Herschel in 1798.
8.9-mag NGC 6946 was discovered by
William Herschel on September 9, 1798.
NGC 6946 is a rather nearby spiral galaxy, which at one time was suspected
to be an outlying member of the
Local Group
(Hubble 1936).
It is highly obscured by interstellar matter of the
Milky Way galaxy, as it is quite close to
the galactic plane.
Ten supernovae have been detected in NGC 6946 as of this writing
(September 2019):
- SN 1917A
occurred on July 19, 1917 when it was discovered by Ritchey.
This supernova, situated 37"W and 105"S of the galaxy's nucleus, lightened
up to 14.6 mag.
- SN 1939C
was discovered by Fritz Zwicky on July 17, 1939 (see
IAU Circular No. 793),
215"W and 24"N of the galaxy's center, and peaked at 13.0 mag.
- SN 1948B
was found by Mayall when it flashed up on July 6, 1948, 222"E and
60"N of the galaxy's nucleus; it reached magnitude 14.9 (see
IAUC 1161)
- SN 1968D brightened up on February 29, 1968 the leap day, 45"E and
20"N of the galaxy's center, and became as bright as 13.5 mag. This supernova
was discovered by Wild and Dunlap, and was found to be of type II (see
IAUC 2057 and IAUC 6045)
- SN 1969P occurred on December 11, 1969, 5"W and 180"S of the nucleus
and reached mag 13.9. It was found by Rosino (see
IAUC 2305)
- SN 1980K was discovered by Wild on October 28, 1980 when it occurred
280"E and 166"S of the galaxy's center; it reached mag 11.4 (see
IAUC 3532 and AJ 111, 2017)
- SN 2002hh, of type II, was discovered by the LOTOSS project (W. Li)
on unfiltered KAIT images taken on Oct. 31, 2002, 60".9 west and 114".1
south of the nucleus of NGC 6946 at about 16.5 mag, and reached about
mag 15.0 at its maximum.
- SN 2004et, another type II supernova, was found by Stefano Moretti
in the evening of September 22, 2004, located 247".1 east and 115".4 south of
the nucleus of NGC 6946 when it was at a brightness of 12.8 mag. It peaked at
12.3 mag on September 30, 2004.
- SN 2008S, of type IIn-pec, was discovered on February 1, 2008 by
Ron Arbour, and located 53" west and 196" south of the nucleus of NGC 6946
at about mag 18.0, and reached its maximum of mag 16.5 on February 5 of the
same year, 2008.
- SN 2017eaw, type IIP, was discovered on May 14, 2017 by Patrick
Wiggins, located 61".0 west and 143".0 north of the galaxy's center.
It reached a maximum of mag 12.6 on May 20.
With this number of supernovae which have been found in this galaxy,
NGC 6946 is leading the statistics quite comfortably,
currently with three SNe more than the follow-ups
M83 and M61.
In the SAC 110 best NGC object list.
In the RASC's Finest N.G.C. Objects
Objects list.
Caldwell 12 in Patrick Moore's list.
NED data of NGC 6946
SIMBAD Data of NGC 6946
Publications on NGC 6946 (NASA ADS)
Observing Reports for NGC 6946 (IAAC Netastrocatalog)
NGC Online data for NGC 6946
References
Hartmut Frommert
Christine Kronberg
[contact]
Last Modification: September 16, 2019