Constellation Delphinus (Dolphin)

Delphinus
Delphinus: IAU Constellation Map [150]

Properties

Delphinus is located northeast of the bright star Atair in Aquila. It is very small with an area of 189 square degrees, but has a memorable shape with the outlines of a diamond and a tail at the southern end. Together with the neighboring constellations Vulpecula and Sagitta, which are also small, Delphinus lies in a star-rich area of the Milky Way, where Novae often light up. Delphinus is one of the few constellations that still lives up to its name in its current form. It culminates around midnight on July 31st. [9, 15]

Stars with Proper Names:

  • α Delphini: Sualocin, Scalovin, Svalocin, Nicolaus
  • β Delphini: Rotanev, Rotanen, Venator
  • ε Delphini: Deneb Dulfim, Deneb El Delphinus
Data for constellation Delphinus [150]
IAU NameDelphinus
IAU GenitiveDelphini
IAU Abbr.Del
English NameDolphin
Season (47° N)April … November
Right Ascension20h 14m 15s … 21h 09m 00s
Declination2° 24' 08" … 20° 56' 24"
Area189 deg2
Neighbours (N↻)Vul, Sge, Aql, Aqr, Equ, Peg

Deep-Sky Object Descriptions

Mythology and History

The constellation was already known to the ancient Greeks and refers to the deeper relationship between humans and these very intelligent marine animals. According to legend, dolphins were messengers of the sea god Poseidon and, among other things, saved his son Arion from drowning when he was attacked by pirates on a ship. [25]

Another beautiful story about Delphinus is this: The Roman sea god Neptune, who is also identified with the Greek Poseid, fell in love with Amphitrite, one of the graceful sea nymphs. The sea nymphs were not only very beautiful beings, but they also had the ability to soothe strong winds that churned the sea. However, Amphitrite initially had no interest in Neptune. Therefore, the sea god convinced a dolphin to advertise him at Amphitrite. The dolphin was successful and was able to win the beauty for Neptune. In gratitude for his commitment, Neptune transformed the dolphin into a constellation that still shines in the northern firmament today.

Much more recent are the names of the two brightest stars, Sualocin and Rotanev. These names appeared for the first time in the Palermo Catalog of 1814. Years later it was only realized that these names, read backwards, resulted in the name Nicolaus Venator, the Latinized form of Niccolo Cacciatore. He was the assistant to the Italian astronomer Giuseppe Piazzi at the 19th century Palermo Observatory.[7, 55]

Catalogs

Yale Bright Star Catalogue, 5th Revised Ed. (Hoffleit+, 1991) [154]
HR B F RA [hms] Dec [dms] vMag spType dMag Sep ["]
7836120 30 18.0+10 53 456.08 A1eShell 1.80.9
7852ε220 33 12.8+11 18 124.03 B6III
7858η320 33 57.0+13 01 385.38 A3IV s
7871ζ420 35 18.5+14 40 274.68 A3V
7882β620 37 33.0+14 35 433.63 F5IV 1.00.6
7883ι520 37 49.1+11 22 405.43 A2V
7892θ820 38 43.9+13 18 545.72 K3Ib
7896κ720 39 07.8+10 05 105.05 G2IV 4.8203.6
7906α920 39 38.3+15 54 433.77 B9IV 7.543.4
79181020 41 16.2+14 34 595.99 gK4
7928δ1120 43 27.5+15 04 284.43 A7IIIpDel Del
7947γ11220 46 38.7+16 07 285.14 F7V 1.09.8
7948γ21220 46 39.5+16 07 274.27 K1IV 1.09.8
79531320 47 48.3+06 00 305.58 A0V 3.61.4
79731520 49 37.8+12 32 435.98 F5V 5.2108.0
79741420 49 48.3+07 51 516.33 A1V s
80111720 55 36.7+13 43 175.17 K0III
80121620 55 38.6+12 34 075.58 R A4V 6.536.0
80301820 58 25.9+10 50 215.48 gG6 4.6198.2

«Revised New General Catalogue and Index Catalogue», Dr. Wolfgang Steinicke, 2021 [277]
NameRADecTypeBmagVmagDimDreyer DescriptionIdentification
NGC 6891 20 15 08.9+12 42 17PN11.710.50.35planetary, stellar = 9.5 mPK 54-12.1, CS=12.4
NGC 6905 20 22 23.0+20 06 18PN11.911.11.20!!, planetary, B, pS, R, 4 S st nrPK 61-9.1, CS=13.5, Blue flash nebula
NGC 6917 20 27 28.4+08 05 50Gx (S)14.313.41.40 × 1.0vF, S, att to a S *UGC 11563, MCG 1-52-7, CGCG 399-10, IRAS 20249+0755
NGC 6927 20 32 38.1+09 55 01Gx (S0)15.514.50.50 × 0.2eF, lEMCG 2-52-16, CGCG 424-20, NPM1G +09.0505
NGC 6927 A20 32 36.7+09 53 00Gx (E5)16.515.50.30 × 0.1eF, lEMCG 2-52-15
NGC 6928 20 32 50.1+09 55 39Gx (SBab)13.212.22.10 × 0.6pB, pL, mEIC 1325, UGC 11589, MCG 2-52-17, CGCG 424-21, IRAS 20304+0945
NGC 6930 20 32 58.8+09 52 26Gx (SBab)13.612.81.20 × 0.5F, mEIC 1326, UGC 11590, MCG 2-52-18, CGCG 424-22, IRAS 20305+0942
NGC 6933 20 33 38.2+07 23 16*2pB, vS, h 2081 f
NGC 6934 20 34 11.6+07 24 17GCL (VIII)8.97.10globular, B, L, R, rrr, st 16…, * 9 pGCL 117
NGC 6944 20 38 23.8+06 59 49Gx (E-S0)14.813.81.50 × 0.6pF, S, RMCG 1-52-17, CGCG 399-25, NPM1G +06.0514
NGC 6944 A20 38 11.2+06 54 09Gx (SBd/P)14.914.30.90 × 0.7pF, S, RMCG 1-52-16, CGCG 399-24
NGC 6950 20 41 05.0+16 37 14*Grp10.00Cl, P, vlC
NGC 6954 20 44 03.3+03 12 34Gx (S0-a)14.113.21.00 × 0.6F, S, vlEUGC 11618, MCG 0-53-1, CGCG 374-4, KARA 886
NGC 6955 20 44 17.9+02 35 43Gx (Sbc)14.413.61.40 × 1.3eF, pL, RUGC 11621, CGCG 374-5, NPM1G +02.0476
NGC 6956 20 43 53.7+12 30 44Gx (SBb)13.112.31.90 × 1.9vF, S, stellar, ** attUGC 11619, MCG 2-53-1, CGCG 425-1, IRAS 20415+1219
NGC 6957 20 44 47.7+02 34 50Gx (Sc)15.114.40.50 × 0.4vF, S, RCGCG 374-7
NGC 6969 20 48 27.6+07 44 25Gx (Sa)15.014.11.10 × 0.3F, pL, EUGC 11633, MCG 1-53-1, CGCG 400-2, KARA 889
NGC 6971 20 49 23.7+05 59 43Gx (Sb)14.513.71.10 × 0.9vF, S, RUGC 11637, MCG 1-53-2, CGCG 400-3
NGC 6972 20 49 58.9+09 53 59Gx (S0-a)14.213.31.10 × 0.5F, S, RUGC 11640, MCG 2-53-4, CGCG 425-11, NPM1G +09.0513
NGC 6988 20 55 48.9+10 30 30Gx (S)15.214.60.50 × 0.5eF, pL, RCGCG 425-20, NPM1G +10.0499
NGC 7003 21 00 42.3+17 48 17Gx (Sbc)13.813.01.10 × 0.8vF, vS, lE, * 15 close fUGC 11662, MCG 3-53-8, CGCG 448-27, IRAS 20584+1736
NGC 7006 21 01 29.5+16 11 17GCL (I)10.63.60B, pL, R, gbMGCL 119
NGC 7025 21 07 47.4+16 20 09Gx (Sa)13.712.81.90 × 1.2vF, vS, R, stellUGC 11681, MCG 3-54-1, CGCG 449-3, KARA 897, IRAS 21054+1607
NGC 7028 21 08 15.0+18 28 48NFvF, S, vlE
IC 1320 20 26 25.7+02 54 34Gx (Sb)14.413.61.00 × 0.6pF, S, R, gbM, rUGC 11560, MCG 0-52-9, CGCG 373-8, IRAS 20239+0244
IC 1325 20 32 50.1+09 55 39SBab13.212.22.10 × 0.6vF, S, sev F st inv, sp of 2NGC 6928, UGC 11589, MCG 2-52-17, CGCG 424-21, IRAS 20304+0945
IC 1326 20 32 58.8+09 52 26SBab13.612.81.20 × 0.5eeF, S, mE, pF * s, nf of 2NGC 6930, UGC 11590, MCG 2-52-18, CGCG 424-22, IRAS 20305+0942
IC 1329 20 43 42.3+15 35 16*GrpeeF, pL, R, bet 4 st, v diffic
IC 1359 21 08 43.0+12 29 02Gx (S?)14.813.91.20 × 0.4eeF, eS, stellar, eF * attUGC 11684, MCG 2-54-1, CGCG 426-4, 2ZW 103
IC 5080 21 02 33.0+19 12 51Gx (E2)15.414.40.50 × 0.4F, vS, R, stell NCGCG 448-31, NPM1G +19.0518
IC 5081 21 03 01.2+19 11 21Gx (S)15.514.70.30 × 0.2vF, vS, R, stell NCGCG 448-32

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
25«Das Taschenbuch vom Sternenhimmel» von Peter von Eynern; Wilhelm Heyne Verlag, München, 1972
55Eye On The Sky: Delphinus, Equuleus by Deborah Byrd; Astronomy 10/92, p.48
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)