NEAT SOUTHERN PLANETARIES : 26a
Pb 5 in Vela
Pb 5 / He2-24 / Sa2-40 / Wray 16-39 / ESO 261-4 / PK
268+2.1 / PN G268.4+02.4 (09162-4529) is a small faint planetary in
Vela discovered by M. Peimbert and G. Batiz in 1960 — some two
years before K.G. Henize had rediscovered it in his mostly southern
galactic plane Hα survey. The
discoverers have only nine new “Pb” PNe that are assigned to them.
[See Appendix 1 : Tables 1 & 2 that listed all the catalogued or
recognised faint Pb and Pc PNe,] Pb5 appears in Uranometria 2000.0
(Map 398) as PK 268+2.1 and does not feature in any of the other star
maps except the Millennium Star Atlas.
Fig. 4. PB 5 / He2-24 Wide Field. CDS
Aladin Colour Image about AAO Red (red), J plates (blue), average
(green) 11½′×11½′ in size.
Fig. 5. Closeup of Pb 5 / He2-24. CDS
Aladin Colour Image Combined AAO Red (red), J plates (blue), average
(green). Image about 30′×30′ shows the small
planetary of 14.8v magnitude. Inspection, though not mentioned in the
literature, shows one or even two stars superimposed over the
nebulous object. Does this suggest the PNN is a double star or just
appearing between us and the planetary?
Pb 5, placed in a moderately starry field, being found some
2.5°SE (PA 145°) from 2.1 mag. λ Vel / Lambda Velorum / Al Suhail
(09080-4326), or alternatively, it lies 3.1°SSE (168°) from
NGC 2792.
It is classed as V-V PNe Type I or 1 — “stellar”, though against this it is
only slightly less than 5 arcsec. At 14.8V, 14.2p, 16.0B, 13.3R
magnitude, Pb 5 appears under high magnification and very dark skies
in 20cm. as a faint and tiny smudge, that will be seen with care
using averted vision. You will, however, positively need some finder
chart or image to truly bag the object. Telescopes above 25cm. should
have no problems seeing its tiny round disk. In 30cm., Pb 5 appears
much like a tiny colourless, or perhaps slightly more greyish, round
haze. An O-III filter is not probably very useful in
this instance, except perhaps when using the largest of
apertures.
I think it is more likely to be about 3 to 4 arcsec in diameter,
smaller than the usually stated 5 arcsec. The PNN central star is
18.67V magnitude as is obviously well beyond amateur or even some
professional telescopes! Overall radial velocity is +53.3
km.s-1 away from us. Very little is known about this
planetary, and there seems no current estimate of distance or true
size in the literature (2011).
Recommended for true deep-sky observers and certainly not one for
the faint of heart! A field chart or using the wider image given here
is highly recommended.
See Appendix 1, which Tabulates all known Pb and Pc PNe.
References to Pb 5
- Peimbert, M., Batiz, G., “New
Planetary Nebulae [Nuevas nebulosas planetarias.]”,
Bol.Obs Tonatz.Tacuh., 2, Pt. 19, 19 (1960)
- Peimbert, M., Costero, R., “New
Planetary Nebulae II; [Nuevas Nebulosas Planetarias II]”,
Bol.Obs Tonatz.Tacuh., 3, 33 (1961)
- Phillips, J.P., Marquez-Lugo, R.A. “Mid- and Far-Infrared Photometry of
Galactic Planetary Nebulae with the AKARI All-Sky Survey.”,
Rev.Mex.Astron.Astrofis., 47, 83 (2011)
Appendix 1 : Catalogue of Pb and Pc Planetaries
All Diameters (arcsec) in the Table 1 & 2 are from the
original paper, unless otherwise stated. Objects Pb 1-10 appear in
Paper I. Objects Pc 11-24 appear in Paper II, but only four
are accepted as new PNe in SIMBAD but as nine in Phillips
& Marquez-Lugo (2011). The later ones are now instead labelled
Pc xx. SSV (2008) is paper for distances derived by
Stanghellini, L., Shaw, R.A., Villaver, E. (See References.)
Table 1: Catalogue of All Pb Planetaries (1960)
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No. Other PN G RA (2000) Dec (2000) Mag Diam. D. Diam. N
Designations hh mm ss.s ° ′ ″ arcsec kpc. (pc.)
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Pb01 Sa 2-2 ARO 225 226.4-03.7 07 02 46.8 −13 42 34.7 18×13.2 ?? ?? 1
Pb02 He2-08 Sa2-24 263.0-05.5 08 20 40.2 −46 22 58.8 13.3B 03 5.75 0.084 2
Pb03 He2-16 Sa2-33 269.7-03.6 08 54 18.3 −50 32 22.3 13.0B 07 3.4 0.115 3
Pb04 He2-22 Sa2-38 275.0-04.1 09 15 07.7 −54 52 43.8 11.2 2.81 0.153 4
Pb05 He2-24 Sa2-40 268.4+02.4 09 16 09.6 −42 28 42.8 14.8V 05 ?? ?? -
Pb06 He2-43 Sa-2-58 278.8+04.9 10 13 15.9 −50 18 59.2 17.6V 11 3.55 0.18 5
Pb07 He2-49 Sa2-61 283.8+02.2 10 31 33.4 −55 20 50.5 -- -- -- 6
Pb08 He2-69 Sa2-77 My68 292.4+04.1 11 33 17.7 −57 06 14.0 05 5.15 0.125 7
Pb09 ARO 152 PK 046-03.1 046.3-03.1 19 27 44.8 +10 24 20.8 14.4B 07 3.57 0.121 8
Pb10 ARO 153 PK 048-02.1 048.0-02.3 19 28 14.4 +12 19 36.2 08 3.53 0.137 9
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Notes: (Recent Data from Simbad or Elsewhere)
1. Missing magnitudes are not visual but in J or K
photometry
2. Dist.=9098pc. SSV (2008), increasing true diameter as the
more acceptable 0.132pc.
3. Latest size 15×14″. Dist.=4893pc. SSV (2008),
making the true Diameter as 0.165 pc.
4. Size 21.4×17.5″ Dist.=3680pc. SSV (2008), true
Diameter is then 0.200 pc. PNN WC
5. Size 20.2×17.0″ Dist.=4419pc. SSV (2008), true
Diameter is then 0.235pc.
6. Earlier catalogued My 60. Size 18.2×18.7″.
Dist.=4803pc. SSV (2008) PNN WC
7. Earlier catalogued My 68. 5.0″. Dist.=7299pc. SSV
(2008). PNN WC RV=+21.9km.s-1
8. Size 19.3×14.3″ Dist.=4706pc. SSV (2008)
9. Size 19.3×12.8″ Dist.=4830pc. SSV (2008)
Table 2: Catalogue of Pc Planetaries (1961)
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No. Other PN G RA (2000) Dec (2000) Mag Diam. D. Diam. N
Designations hh mm ss.s ° ′ ″ arcsec kpc. (pc.)
--------------------------------------------------------------------------------------
Pc11 He2-172 ESO 179-11 331.1-05.7 16 37 42.7 −55 42 26.5 11.8B 7.0 ?? ?? 1
Pc12 He2-180 Sa2-162 000.1+17.2 16 43 53.8 −18 57 12.0 13.7B 1.8×1.8 -- -- 2
Pc13 Sa2-155 ESO 453-6 351.9+09.0 16 50 17.1 −30 19 55.5 12.9B ?? ?? ?? 3
Pc14 He2-195 Sa2-171 336.2-06.9 17 06 14.1 −52 30 00.4 16.5V 7.0 4.32 0.15 4
Pc17 He2-246 Sa2-216 343.5-07.8 17 35 41.7 −46 59 48.5 12.9B 5.0 6.12 0.15 5
Pc19 ARO 136 PK 032+07.2 032.1+07.0 18 24 44.5 +02 29 28.1 13.8B 2.8 6.75 0.09 6
Pc20 ARO 140 PK 031+01.1 031.7+01.7 18 43 03.5 −00 16 37.3 ?? ?? ?? -
Pc21 Sa2-364 ESO 591-16 013.8-07.9 18 45 35.2 −20 34 58.3 13.4 ?? ?? -- 7
Pc22 ARO 160 PK 051-04.1 051.0-04.5 19 42 03.5 +13 50 37.3 ?? ?? ?? 8
Pc24 He1-7 He2-463 066.9-05.2 20 19 38.1 +27 00 11.3 14.0B 5.0 5.78 0.14 9
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Notes: (Recent Data from Simbad or Elsewhere)
1. Data from Simbad but says this is of unknown object
type
2. In SIMBAD, not Philips & Marquez-Lugo (2011).
Dist.=14.35 kpc.!! SSV (2008) RV=-60.8km.s-1
3. Also StWr 4-3. Radial Velocity
(RV)=-74km.s-1
4. ESO 227-5, 17.2B. Size=7.0×7.0″. Dist.=5796pc
SSV (2008) True diam.=0.201pc. PNN WC
5. ESO 279-1 Size=5.0×5.0″. Dist.=8.18kpc. SSV
(2008) True Dia.=0.200pc. RV=-142 km.s-1
6. RV=20.0km.s.-1 13.0R Size=2.8×2.8″.
Dist. 10.39 kpc. SSW (2008)
7. RV=+42km.s-1 Object is oval not round.
8. Discovered by S.P. Apriamasvili in 1959
9. Mag. 12.0R, Size=12×10.7″. Dist.=7856pc SSV
(2008) True Dia.=0.190pc. True Dia.=0.139pc.
Last Update : 24th February 2012
Southern Astronomical Delights ©
(2012)
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