ASTRO: NGC 3801 The Leaf Blower Galaxy (NASA/JPL's name for it)

NGC 3801 is in the center of a small group of NGC galaxies, some north
and south out of my limited field of view. The cluster is located in
the tail of Leo about 170 million light-years distant. It certainly is
an interesting galaxy. Highly disturbed by some encounters in the past
with plumes going every which way and two dust lanes at right angles to
each other. Rather red so apparently the interaction was some time in
the past. It shut down star formation and now only smaller old red
stars are left it would seem. Or is the red color due to it shrouded in
a dust cloud caused by the interaction that masks its blue stars?
Doesn't look like dust reddening to me. NED classes it as S0/a though I
see little indication of any spiral structure. Looks more plane S0 to
me. NGC Project agrees saying simply S0? Note the asteroid trail in
the southern part of the galaxy. This one is very interesting to many
CCD users. I'll have more on it in a bit. Just before posting this
some new information was released -- see below.

Above it is NGC 3802. An edge on spiral that NED also classes S0/a.
Looks like a typical spiral to me so here I can't fathom where the S0
came from. Such galaxies rarely have a nice dust lane in the disks
plane like it has. NGC project says simply S... for a classification.

NGC 3806 is a nice face on barred spiral that is very blue and of rather
faint surface brightness. So while its light comes mostly from new
young stars there aren't many of them or it would be quite a bit
brighter. NED classes it as SABb. The NGC project says Sb/SBb.
Apparently they aren't sure of the bar? Maybe it is an elongated
nucleus rather than a bar?

NGC 3803 is a rather tiny galaxy to make the NGC list. It has a high
surface brightness which attracted visual observers I suppose. It is so
small NED didn't try to classify it. The NGC project called it simply
E. Seems rather blue in color for that classification

NGC 3790 is the only one NED and the NGC Project agree on. NED says
S0/a and the NGC Project SO-a.

Two other galaxies may be members. Though KUG 1137+179 at 190 million
light-years has a somewhat different redshift it doesn't rule it out as
a possible member. NED say is is simply a spiral. CGCG 097-046 is
classed at NED as simply S0 which appears reasonable to me.

As is often the case I came up with a couple possible galaxies not
listed at NED. Both are large faint puffs. I suppose they could be IFN
or something akin to that. I see both in the Sloan image but with no
resolution. They are east and southeast of NGC 3801. I've marked them
with a question mark on the annotated image.

Several galaxy clusters are in the image.
NSCS J114128+174623 has 46 members
NSCS J114131+174924 has 41 members
GMBCG J175.40459+17.65904 has 14 members
GMBCG J175.38869+17.87717 has 10 members
GMBCG J174.85594+17.58540 has a lucky 13 members.

That brings us to the asteroid. I didn't know of its existence until I
looked up what asteroid had wandered into the image. It is (35197)
Longmire at magnitude 18.2. That ring any bells to you CCD users? It
did for me. I had to look up the naming citation to see if it was the
Longmire I was thinking of. I figured my guess would be wrong but was
happy to see I was right. Here's the citation.

"Matthew J. Longmire (b. 1958) is an electrical engineer who co-founded
a small CCD brand that in 1991 developed star tracking equipment,
sparking the CCD revolution in the world of amateur astronomy."

He's one of the founders of SBIG that made my CCDs and the ST-4 I used
to guide my film images for many years. In fact it is the ST-4 the
citation refers to. Apparently they have a thing about no company names
in naming citations. Serendipity strikes again.

Now for the new information. I received an email from JPL/NASA and a
club member about a press release from JPL/NASA about a "cosmic leaf
blower" galaxy. Yep they are talking about NGC 3801. Turns out my
surmises are pretty much correct. The above was written a couple days
ago as I worked on the annotated image. I left it alone other than the
last sentence. Compare my guesses to the press release. Sometimes I
get it pretty close to right. Note the side bar transposes the galaxy
to NGC 3810. I wasn't going to release this one so soon and out of
order as I didn't like the galaxy's color. Just too red for a spiral.
I was going to look again at the data to see if I screwed something up
but the color matches the press releases description -- their image is
false color so of no help. Though I don't see the blue stars Galex sees
in the UV part of the spectrum. Here's the news release from April 3.
http://www.jpl.nasa.gov/news/news.cf...&msource=12094

14" LX 200R @ f/10, L=4x10' RGB=2x10', STL-11000XM, Paramount ME

Cropped image enlarged to 0.8" per pixel to include NGC 3806.

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

Amazing detail Rick.
And you have almost every kind of galaxy in one image (although I did not
find a ring galaxy ;-)

Stefan

"Rick Johnson" schrieb im Newsbeitrag
. com...
NGC 3801 is in the center of a small group of NGC galaxies, some north
and south out of my limited field of view. The cluster is located in
the tail of Leo about 170 million light-years distant. It certainly is
an interesting galaxy. Highly disturbed by some encounters in the past
with plumes going every which way and two dust lanes at right angles to
each other. Rather red so apparently the interaction was some time in
the past. It shut down star formation and now only smaller old red
stars are left it would seem. Or is the red color due to it shrouded in
a dust cloud caused by the interaction that masks its blue stars?
Doesn't look like dust reddening to me. NED classes it as S0/a though I
see little indication of any spiral structure. Looks more plane S0 to
me. NGC Project agrees saying simply S0? Note the asteroid trail in
the southern part of the galaxy. This one is very interesting to many
CCD users. I'll have more on it in a bit. Just before posting this
some new information was released -- see below.

Above it is NGC 3802. An edge on spiral that NED also classes S0/a.
Looks like a typical spiral to me so here I can't fathom where the S0
came from. Such galaxies rarely have a nice dust lane in the disks
plane like it has. NGC project says simply S... for a classification.

NGC 3806 is a nice face on barred spiral that is very blue and of rather
faint surface brightness. So while its light comes mostly from new
young stars there aren't many of them or it would be quite a bit
brighter. NED classes it as SABb. The NGC project says Sb/SBb.
Apparently they aren't sure of the bar? Maybe it is an elongated
nucleus rather than a bar?

NGC 3803 is a rather tiny galaxy to make the NGC list. It has a high
surface brightness which attracted visual observers I suppose. It is so
small NED didn't try to classify it. The NGC project called it simply
E. Seems rather blue in color for that classification

NGC 3790 is the only one NED and the NGC Project agree on. NED says
S0/a and the NGC Project SO-a.

Two other galaxies may be members. Though KUG 1137+179 at 190 million
light-years has a somewhat different redshift it doesn't rule it out as
a possible member. NED say is is simply a spiral. CGCG 097-046 is
classed at NED as simply S0 which appears reasonable to me.

As is often the case I came up with a couple possible galaxies not
listed at NED. Both are large faint puffs. I suppose they could be IFN
or something akin to that. I see both in the Sloan image but with no
resolution. They are east and southeast of NGC 3801. I've marked them
with a question mark on the annotated image.

Several galaxy clusters are in the image.
NSCS J114128+174623 has 46 members
NSCS J114131+174924 has 41 members
GMBCG J175.40459+17.65904 has 14 members
GMBCG J175.38869+17.87717 has 10 members
GMBCG J174.85594+17.58540 has a lucky 13 members.

That brings us to the asteroid. I didn't know of its existence until I
looked up what asteroid had wandered into the image. It is (35197)
Longmire at magnitude 18.2. That ring any bells to you CCD users? It
did for me. I had to look up the naming citation to see if it was the
Longmire I was thinking of. I figured my guess would be wrong but was
happy to see I was right. Here's the citation.

"Matthew J. Longmire (b. 1958) is an electrical engineer who co-founded
a small CCD brand that in 1991 developed star tracking equipment,
sparking the CCD revolution in the world of amateur astronomy."

He's one of the founders of SBIG that made my CCDs and the ST-4 I used
to guide my film images for many years. In fact it is the ST-4 the
citation refers to. Apparently they have a thing about no company names
in naming citations. Serendipity strikes again.

Now for the new information. I received an email from JPL/NASA and a
club member about a press release from JPL/NASA about a "cosmic leaf
blower" galaxy. Yep they are talking about NGC 3801. Turns out my
surmises are pretty much correct. The above was written a couple days
ago as I worked on the annotated image. I left it alone other than the
last sentence. Compare my guesses to the press release. Sometimes I
get it pretty close to right. Note the side bar transposes the galaxy
to NGC 3810. I wasn't going to release this one so soon and out of
order as I didn't like the galaxy's color. Just too red for a spiral.
I was going to look again at the data to see if I screwed something up
but the color matches the press releases description -- their image is
false color so of no help. Though I don't see the blue stars Galex sees
in the UV part of the spectrum. Here's the news release from April 3.
http://www.jpl.nasa.gov/news/news.cf...&msource=12094

14" LX 200R @ f/10, L=4x10' RGB=2x10', STL-11000XM, Paramount ME

Cropped image enlarged to 0.8" per pixel to include NGC 3806.

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