RE: NGC 3158 observing challenge

From: Mark Wagner (mgw@No-Spam)
Date: Thu Feb 28 2002 - 11:07:40 MST

  • Next message: Jeffrey D. Gortatowsky: "Re: NGC 3158 observing challenge"

    This was an area I observed from Dino last month. Here is my entry:

    NGC3158 - Galaxy in group in Leo Minor. This is a wonderful field. I
    counted 9 galaxies. NGC3158 is easily the brightest of the group and stands
    alone just NNW of a chain of several other galaxies running E/W in close
    proximity. Others observed were MGC7-21-19, NGC3159, NGC3161, NGC3163 (four
    in a line), NGC3151, NGC3150, NGC3152 and NGC3160. The seeing had softened
    so I did not try for the dimmer ones in the
    area. Check this out (15 arcminutes wide/tall):

    http://archive.stsci.edu/cgi-bin/dss_search?v=1&r=10+13+50.56&d=%2B38+45+52.1&e=J2000&h=15.0&w=15.0&f=gif&c=none&fov=NONE&v3=

    At 09:32 AM 2/28/2002 -0800, you wrote:
    >Steve,
    >
    >Taking a look at your list it looks like NGC3158, NGC3151, NGC3152, and
    >maybe just barely NGC3163 might be visible in my C8, ranging from a SB of
    >13.5 down to 14 for 3163. With good conditions could I expect to see these
    >objects or are they too small to be seen despite being in a range of
    >magnitudes I have observed with my scope.
    >
    >Also, every reference I can find for NGC 3160 list it as an apparent mag of
    >15 to 15.3 yet you have it listed as V=14.4 and SB=12.8. Are my references
    >wrong?
    >
    >Cheers,
    >
    >Dave
    >
    >
    >
    >-----Original Message-----
    >From: Steve Gottlieb [mailto:sgottlieb@No-Spam]
    >Sent: Wednesday, February 27, 2002 10:43 PM
    >To: sf-bay-tac@No-Spam
    >Cc: tac-sac@No-Spam
    >Subject: [TAC] NGC 3158 observing challenge
    >
    >
    >I haven't thrown out a list of observing challenges in awhile, so here's a
    >neat galaxy cluster for 12-inch and larger scopes, mostly within 40' of NGC
    >3158 in Leo Minor. I first ran across this group sometime in the early or
    >mid '80's after it was featured in a Deep Sky Wonders column by Scotty
    >Houston and found most of the objects with a 13.1" Odyssey I. I worked
    >through the cluster using a photo of the cluster (before the days of
    >computerized sky charts)
    >
    >William Herschel discovered the brightest two members of the group (NGC 3158
    >and NGC 3163), but the fainter members were found by Bigourdan using a
    >16-inch refractor at the Paris Observatory or using Lord Rosse's 72-inch at
    >Birr Castle. Below the NGC listings are even fainter galaxies for 16-inch
    >or
    >larger scopes. Finally, there is Shakhbazin 49 in the vicinity -- a compact
    >cluster of extremely compact galaxies. Good luck!
    >Steve
    >
    >NGC 3150 = MCG +07-21-017 = CGCG 211-019
    >10 13 26.3 +38 39 27
    >V = 14.5; Size 0.8x0.6
    >
    >17.5": faint, small, slightly lower surface brightness than N3151 2.3' S. A
    >mag 12 star is 2.0' WSW and a mag 14 star is 1.8' NNW.
    >************************************************************
    >
    >NGC 3151 = MCG +07-21-018 = CGCG 211-020
    >10 13 29.1 +38 37 11
    >V = 13.8; Size 0.8x0.4; SB = 13.5; PA = 170d
    >
    >17.5": fairly faint, very small, weak concentration. A mag 12 star is 2.0'
    >NE. Forms a pair with N3150 2.3' N. An extremely faint galaxy is 55" east
    >of center (2MASXi J1013337+383705).
    >************************************************************
    >
    >NGC 3152 = MCG +07-21-018A = CGCG 211-021
    >10 13 34.1 +38 50 35
    >V = 14.2; Size 1.0x0.6; SB = 13.5; PA = 80d
    >
    >17.5": faint, small, round. A mag 15 star is off the NE edge 0.8' from
    >center. N3158 lies 5.5' SE and N3160 4.1' E.
    >************************************************************
    >
    >NGC 3158 = U05511 = MCG +07-21-020 = CGCG 211-022
    >10 13 50.5 +38 45 53
    >V = 11.9; Size 2.0x1.8; SB = 13.3
    >
    >17.5": fairly bright, irregular round or slightly elongated, small bright
    >core. Brightest in N3158 group with N3159 6.7' SSE, N3160 4.7' N and N3152
    >5.5' NW.
    >************************************************************
    >
    >NGC 3159 = MCG +07-21-021 = CGCG 211-023 = NPM1G +38.0190
    >10 13 52.8 +38 39 16
    >V = 13.6; Size 0.8x0.7
    >
    >17.5": fairly faint, small, irregularly round, small bright core. This
    >member of the N3158 group is the first of three with N3161 1.2' E and N3163
    >2.7' E. N3158 lies 6.7' NNW.
    >************************************************************
    >
    >NGC 3160 = U05513 = MCG +07-21-023 = CGCG 211-024
    >10 13 55.1 +38 50 34
    >V = 14.4; Size 1.3x0.2; SB = 12.8; PA = 140d
    >
    >17.5": faint, small, edge-on NW-SE. Member of N3158 group with N3158 4.7'
    >S.
    >************************************************************
    >
    >NGC 3161 = MCG +07-21-022 = CGCG 211-025 = NPM1G +38.0191
    >10 13 59.2 +38 39 26
    >V = 13.5; Size 0.8x0.5; SB = 14.8; PA = 10d
    >
    >17.5": this member in the N3158 group is small and the faintest of three
    >with
    >close companions N3159 1.2' W and N3163 1.5' E. Even surface brightness and
    >visible with direct vision.
    >************************************************************
    >
    >NGC 3163 = U05517 = MCG +07-21-026 = CGCG 211-027
    >10 14 07.1 +38 39 09
    >V = 13.3; Size 1.1x1.1
    >
    >17.5": fairly faint, small, round, bright core. Brightest and third of
    >three
    >with N3161 1.5' W and N3159 2.7' W.
    >*************************************************************
    >MCG +07-21-030 = CGCG 211-030 = NPM1G +39.0230
    >10 14 45.3 +38 58 51
    >Size 0.6x0.6
    >
    >17.5": very faint, very small, round, 25" diameter. Picked up while
    >starhopping to Shkh 49 located 7.4' SE. Located 1.2' NW of a mag 11 star
    >about 17' NW of N3158.
    >************************************************************
    >
    >2MASXi J1013337+383705
    >10 13 33.8 +38 37 06
    >
    >17.5": extremely faint and small. Just visible for moments as a threshold
    >knot 0.9' E of N3151. A faint star is at the ENE edge. Located in the
    >N3158
    >group. Verified on POSS.
    >************************************************************
    >
    >2MASXi J1013394+384443
    >10 13 39.5 +38 44 44
    >
    >17.5": extremely faint, stellar, estimate V = 16. This anonymous galaxy is
    >a
    >member of the N3158 group and is located just N of a faint star which is 3'
    >SW of N3158. Verified on POSS.
    >************************************************************
    >
    >MCG +07-21-019
    >10 13 47.9 +38 40 32
    >V = 14.1; Size 0.5x0.4; SB = 12.2
    >
    >17.5": extremely faint, at visual threshold. Appears similar to the N3159,
    >N3161, N3163 trio in size but very low surface brightness. Located 2' NW of
    >N3159 in the N3158 group.
    >************************************************************
    >
    >Shakhbazin 49
    >10 15 19.0 +38 55 28
    >
    >17.5": this challenging compact group was a marginal object at 220x-280x.
    >At
    >220x an extremely faint knot, perhaps 15", was glimpsed several times with
    >averted vision, using a finder chart. At 280x, there was a strong
    >impression
    >of two very close 16th+ magnitude stellar objects, though could not view
    >both
    >objects simultaneously. Located 1.5' NE of a mag 10.5 star and 20' NW of
    >the
    >N3158 cluster.
    >************************************************************



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