Constellation Octans (Octant)

Octans
Octans: IAU Constellation Map [150]

Properties

The constellation Octans is at the south celestial pole. But this is the only thing that distinguishes this inconspicuous, amorphous part of the sky. There is no counterpart to the northern pole star in the southern sky: the closest star that is just visible to the naked eye is σ Octantis (5.5 mag), which is about 1 degree away from the pole. The constellation area is 291 square degrees. [9, 15]

Stars with Proper Names:

  • σ Oct: Polaris Australis
Data for constellation Octans [150]
IAU NameOctans
IAU GenitiveOctantis
IAU Abbr.Oct
English NameOctant
Season (47° N)Not visible
Right Ascension00h 00m 00s … 24h 00m 00s
Declination-90° 00' 00" … -74° 18' 14"
Area291 deg2
Neighbours (N↻)Ind, Pav, Aps, Cha, Men, Hyi, Tuc

History

The constellation is reminiscent of an angle measuring device that was invented by John Hadley in 1730 and used to measure the positions of the stars - a forerunner of the sextant. The original name of the constellation reminds of the inventor: Octans Hadleianus. Like the other technical and scientific equipment in the southern sky, it was introduced in the middle of the 17th century by the French Abbé Nicolas Louis de Lacaille. [7]

Catalogs

Yale Bright Star Catalogue, 5th Revised Ed. (Hoffleit+, 1991) [154]
HR B F RA [hms] Dec [dms] vMag spType dMag Sep ["]
30γ300 10 02.1-82 13 265.28 G8III
3678ζ08 56 41.1-85 39 475.42 A8-9IV
4312η10 59 13.8-84 35 386.19 A1V
4870ι12 54 58.6-85 07 245.46 K0III 0.50.6
5084κ13 40 55.5-85 47 105.58 Am
5339δ14 26 54.9-83 40 044.32 K2III
5525π115 01 50.8-83 13 405.65 G8-K0III
5545π215 04 46.7-83 02 185.65 G8Ib
5557ω15 11 08.3-84 47 155.91 B9.5V
5729ρ15 43 16.8-84 27 555.57 A2V
6721χ18 54 46.9-87 36 215.28 K3III
6829φ18 23 36.1-75 02 395.47 A0V
7228σ21 08 46.2-88 57 235.47 F0III
7863μ120 42 02.9-76 10 506.00 F4III-IV
7864μ220 41 43.7-75 21 026.55 G5III 0.617.0
8021α21 04 43.0-77 01 265.15 A7III+G2III
8254ν21 41 28.5-77 23 243.76 K0III 0.1
8280λ21 50 54.3-82 43 095.29 G8-K0III 2.32.8
8471ψ22 17 50.5-77 30 425.51 F3III
8481ε22 20 01.5-80 26 235.10 M5III
8505υ22 31 37.4-85 58 025.77 K0III
8630β22 46 03.3-81 22 544.15 A9IV-V
8663ξ22 50 22.9-80 07 275.35 B6IV
8862τ23 28 03.7-87 28 565.49 K2III
9032γ123 52 06.4-82 01 085.11 G7III
9061γ223 57 32.7-82 10 125.73 K0III
9084θ00 01 35.7-77 03 574.78 K3III

Revised+Historic NGC/IC, Version 22/9, © Dr. Wolfgang Steinicke [277]
Galaxies
NameRADecTypebMagvMagDimDreyer DescriptionIdentification, Remarks
NGC 257301 41 53.2-89 20 03SBc14.113.51.9 × 0.7F, S, R, glbM, Polariss AustrESO 1-1, IRAS 02425-8934, Polarissima australis
NGC 2573 A23 12 14.6-89 07 27SBb14.713.92.1 × 0.6F, S, R, glbM, Polariss AustrESO 1-9, AM 2247-892, IRAS 22443-8923
NGC 2573 B23 07 32.0-89 06 55IBm15.114.51.5 × 0.5F, S, R, glbM, Polariss AustrESO 1-8, AM 2240-892
NGC 643818 22 15.9-85 24 06S012.711.71.6 × 1.4pB, R, vgbMESO 10-1, AM 1806-852
NGC 6438 A18 22 33.0-85 24 22Ring B12.611.62.7 × 1pB, R, vgbMESO 10-2, AM 1806-852, IRAS 18061-8525
NGC 655718 21 24.7-76 34 58S013.912.91.6 × 1.1vF, vS, R, glbMESO 45-1, AM 1814-763
NGC 692020 43 57.1-80 00 01S012.411.21.8 × 1.5pB, cS, R, psmbMESO 26-4, AM 2036-801
NGC 709521 52 24.8-81 31 53Sc12.211.54 × 3.3F, pL, R, vglbM, * 13 invESO 27-1, FAIR 353, IRAS 21457-8145
NGC 709821 44 16.0-75 06 39SBa12.211.34 × 2.6pF, R, g, psmbM, am stESO 48-5, IRAS 21393-7520
NGC 763723 26 28.3-81 54 40Sc13.212.52.1 × 1.9vF, pL, R, vlbM, * nrESO 12-1, AM 2322-821, IRAS 23226-8211
IC 433314 05 19.5-84 16 23S014.413.41.6 × 0.4eF, vS, eE 40°, suspESO 8-5, IRAS 13574-8402, most southern IC object
IC 486419 40 06.0-77 33 26SBa14.813.51.5 × 0.4eF, vS, eE 70°, vF * sp 1'ESO 25-13, AM 1932-774
IC 491220 06 49.7-77 21 27Sc15.514.81.1 × 0.4eF, vS, F * np 1', suspESO 25-16
IC 492820 10 11.9-77 18 33S16.515.70.7 × 0.2eF, vS, eE 25°, eF * n 1', suspESO 46-6, IRAS 20034-7727
IC 502220 41 06.3-76 26 59SBR15.514.70.9 × 0.6eF, S, R, cbM, suspESO 47-5
IC 502520 44 59.6-76 59 04Sbc15.214.41.5 × 0.3vF, vS, cE 125°, bM, suspESO 47-10, FGCE 1510, IRAS 20389-7709
IC 502620 48 27.6-78 04 08Scd15.514.82.3 × 0.3eF, vS, mE 70°, lbM, suspESO 26-6, FGCE 1519
IC 504020 52 19.5-76 41 11Sd15.214.60.8 × 0.6cB, S, R, suspESO 47-14, IRAS 20461-7652

References

7«Der grosse Kosmos-Himmelsführer» von Ian Ridpath und Wil Tirion; Kosmos Verlag; ISBN 3-440-05787-9
9«Drehbare Sternkarte SIRIUS» von H. Suter-Haug; Hallwag-Verlag, Bern
15«Hartung's Astronomical Objects for Southern Telescopes» by David Malin and David J. Frew; Melbourne University Press 1995; ISBN 0-522-84553-3
150IAU: The Constellations, 11. Oktober 2020; iau.org/public/themes/constellations
154Yale Bright Star Catalog, 15. Oktober 2020; tdc-www.harvard.edu/catalogs/bsc5.html
277«Historische Deep-Sky Kataloge» von Dr. Wolfgang Steinicke; klima-luft.de/steinicke (2021-02-17)