ASTRO: NGC 1073

NGC 1073 is a nearby barred spiral in Cetus about 1.4 degrees north of
M77. It is about 45 to 50 million light-years distant as best as I
could determine. Redshift gives the shorter distance and the one Tully
Fisher measurement I found gives the longer estimate. It is classed as
SB(rs)c by NED and SBc II by the NGC Project.

NGC 1073 reminds me of Arp 38 posted recently. Both have a curl of
stars on a spiral arm. Arp took the one in Arp 38 for a separate
galaxy. Even though this one is very similar he didn't include it.
Likely because this one is close enough to better resolve the curl and
see it isn't a galaxy. Still shouldn't that have been a tip off that
the curl in Arp 38 may be the same thing?

It is close enough that its brighter stars can be easily resolved by the
Hubble Space Telescope. They have covered it in a press release. I'll
save my fingers and let you read about the galaxy at
http://www.spacetelescope.org/news/heic1202/ . For some reason the HII
regions are left uncolored in the HST image rather than pink as they
should be in a true color image. Apparently their image is not true
color though it does seem to get the stars and bar reasonably correct.

The article points out three quasars seen right through the galaxy. NED
shows a fourth even closer to the core. Problem is I think this might
be an error. It is listed about the same brightness as the other three
yet I can't find it in my image, the Sloan image nor the HST image which
goes much fainter. I don't know if the press release missed it, skipped
it because it is too faint for even their scope or it doesn't exist.
The last seems most likely to me.

There are other quasars in the area. Most are just out of my field of
view to the south. Most of the Sloan data at NED covers only the very
bottom of my image but for the quasars. The other sources that do cover
the rest of the image don't seem to have any redshift data for the
galaxies, only the quasars. So the annotated image is a bit skimpy.
Except for the two asteroids, one hard to find as it is nearly 21st
magnitude, I probably wouldn't have prepared one. The "bright" 17.9
magnitude asteroid at the bottom right is (37563) 1988 SG2. The other
at an estimated (by the Minor Planet Center) 20.8 magnitude is 2011 TY9.
It has no number because it has yet to complete an orbit since its
discovery last year. According to the Minor Planet Center the first
observation of it was September 24.48 2011. My image was taken
September 25.29 (start). Less than one day later. It was observed by
Pan-STARRS1 atop Haleakala on Maui. I almost beat them (well I didn't
look at the frames until July, 2012).

14" LX200R @ f/10, L=4x10' RGB=2x10', STL-11000XM, Paramount ME

Rick
--
Prefix is correct. Domain is arvig dot net

Another mighty image Rick. Detail, colour etc are perfect.
Discovering a new asteroid would have been a nice bonus.

Stefan

"Rick Johnson" schrieb im Newsbeitrag
...

NGC 1073 is a nearby barred spiral in Cetus about 1.4 degrees north of
M77. It is about 45 to 50 million light-years distant as best as I
could determine. Redshift gives the shorter distance and the one Tully
Fisher measurement I found gives the longer estimate. It is classed as
SB(rs)c by NED and SBc II by the NGC Project.

NGC 1073 reminds me of Arp 38 posted recently. Both have a curl of
stars on a spiral arm. Arp took the one in Arp 38 for a separate
galaxy. Even though this one is very similar he didn't include it.
Likely because this one is close enough to better resolve the curl and
see it isn't a galaxy. Still shouldn't that have been a tip off that
the curl in Arp 38 may be the same thing?

It is close enough that its brighter stars can be easily resolved by the
Hubble Space Telescope. They have covered it in a press release. I'll
save my fingers and let you read about the galaxy at
http://www.spacetelescope.org/news/heic1202/ . For some reason the HII
regions are left uncolored in the HST image rather than pink as they
should be in a true color image. Apparently their image is not true
color though it does seem to get the stars and bar reasonably correct.

The article points out three quasars seen right through the galaxy. NED
shows a fourth even closer to the core. Problem is I think this might
be an error. It is listed about the same brightness as the other three
yet I can't find it in my image, the Sloan image nor the HST image which
goes much fainter. I don't know if the press release missed it, skipped
it because it is too faint for even their scope or it doesn't exist.
The last seems most likely to me.

There are other quasars in the area. Most are just out of my field of
view to the south. Most of the Sloan data at NED covers only the very
bottom of my image but for the quasars. The other sources that do cover
the rest of the image don't seem to have any redshift data for the
galaxies, only the quasars. So the annotated image is a bit skimpy.
Except for the two asteroids, one hard to find as it is nearly 21st
magnitude, I probably wouldn't have prepared one. The "bright" 17.9
magnitude asteroid at the bottom right is (37563) 1988 SG2. The other
at an estimated (by the Minor Planet Center) 20.8 magnitude is 2011 TY9.
It has no number because it has yet to complete an orbit since its
discovery last year. According to the Minor Planet Center the first
observation of it was September 24.48 2011. My image was taken
September 25.29 (start). Less than one day later. It was observed by
Pan-STARRS1 atop Haleakala on Maui. I almost beat them (well I didn't
look at the frames until July, 2012).

14" LX200R @ f/10, L=4x10' RGB=2x10', STL-11000XM, Paramount ME

Rick
--
Prefix is correct. Domain is arvig dot net