Sextans

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Sextans
Sextans
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Abbreviation Sex
Genitive Sextantis
Symbology the Sextant
Right ascension 10 h
Declination
Area 314 sq. deg.
Ranked 47th
Number of main stars 3
Number of stars

(Bayer-Flamsteed)

29
Number of stars with planets

(BF, variable, other stars)

0, 2
Number of bright stars

(magnitude < 3)

0
Number of nearby stars

(Distance < 100 ly)

0
Brightest star α Sex
(App. magnitude 4.49)
Nearest Star 33 Sex
(Distance: 124 ly)
Meteor showers
  • Sextantids
Bordering
constellations
Visible at latitudes between +80° and −80°
Best visible at 21:00 (9 p.m.) during the month of April
For the Ancient Roman coin denomination, see sextans (coin).
For the Sextans Dwarf galaxy, see Sextans (dwarf galaxy).

Sextans (IPA: /ˈsɛkstanz/, Latin: sextant) is a minor equatoral constellation which was introduced in the 17th century by Johannes Hevelius.

Contents

[edit] Notable features

Sextans is not a particularly bright constellation. It has only one star above the fifth magnitude, namely α Sextantis at magnitude 4.49. The constellation contains a few double stars, including γ, 35, and 40 Sextantis. There are few notable variable stars.

[edit] Notable deep sky objects

There are a few galaxies in Sextans. The most notable is NGC 3115 (called the Spindle galaxy), a spiral galaxy of magnitude 9.1 that is seen edge-on. It is believed to be around 20 million light years away. There are a few other galaxies, including NGC 3156, NGC 3165, NGC 3166, and NGC 3169, a group of four galaxies 60 million light years away. NGC 3166 and NGC 3169 are the brightest of the quartet, at tenth magnitude. These two galaxies, which are separated by only around 50,000 light years, are so close to each other that they affect each other's structure. NGC 3156 is of magnitude 12.4, and NGC 3165 is of magnitude 13.9.

Designation Type Right ascension (J2000.0) Declination (J2000.0) Size Mag.
NGC 3115 galaxy 10h 05m 14.1s -07° 43′ 09″ 8.3′ × 3.2′ 9.1
NGC 3166 galaxy 10h 13m 45.6s +03° 25′ 31″ 5.2′ × 2.7′ 10.4
NGC 3169 galaxy 10h 14m 14.8s +03° 28′ 00″ 4.8′ × 3.2′ 10.2

[edit] Mythology

Being a modern constellation, Sextans has no mythology associated with it. It was deigned to represent a sextant, an instrument that Hevelius made frequent use of in his observations.


[edit] Notable and named stars

BD F Mag. Star Names and other designations Right ascension (J2000.0) Declination (J2000.0) Ly away Comments
α 15 4.49 Alpha Sextantis 10h 07m 56.3s −00° 22' 18" 287
γ 8 5.05 Gamma Sextantis, ADS 7555 09h 52m 30.4s −08° 06' 18" 262
β 30 5.09v Beta Sextantis 10h 30m 17.5s −00° 38' 13" 345
δ 29 5.21 Delta Sextantis 10h 29m 28.7s −02° 44' 21" 300
ε 22 5.24 Epsilon Sextantis 10h 17m 37.8s −08° 04' 08" 183
18 5.65 18 Sextantis 10h 10m 55.8s −08° 25' 06"
19 5.77 19 Sextantis 10h 12m 48.3s +04° 36' 53"
35 5.79 35 Sextantis, ADS 7902 10h 43m 20.9s +04° 44' 52" 1013
41 5.79 41 Sextantis, ADS 7942 10h 50m 18.1s −08° 53' 52"
17 5.91 17 Sextantis 10h 10m 07.5s −08° 24' 30"
25 5.97v SS Sextantis, 25 Sextantis 10h 23m 26.5s −04° 04' 27"
6 6.01 6 Sextantis 09h 51m 14.0s −04° 14' 36"
7 6.02 7 Sextantis 09h 52m 12.2s +02° 27' 15" 280
14 6.21 14 Sextantis 10h 06m 47.4s +05° 36' 41"
4 6.24 4 Sextantis 09h 50m 30.1s +04° 20' 37"
33 6.26 33 Sextantis 10h 41m 24.2s −01° 44' 30" 124
36 6.28 36 Sextantis 10h 45m 09.4s +02° 29' 17"
26 6.33 26 Sextantis 10h 26m 36.9s −00° 59' 17"
37 6.38 37 Sextantis 10h 46m 05.7s +06° 22' 24"
13 6.45 13 Sextantis 10h 04m 08.4s +03° 12' 04"
27 6.55 27 Sextantis 10h 26m 46.9s −04° 23' 18"
34 6.57 34 Sextantis 10h 42m 37.5s +03° 34' 59"
40 6.61 40 Sextantis, ADS 7936 10h 49m 17.3s −04° 01' 27" 297
23 6.66v RS Sextantis, 23 Sextantis 10h 21m 02.0s +02° 17' 23"
12 6.70 12 Sextantis 09h 59m 43.1s +03° 23' 05"
9 6.72 9 Sextantis 09h 54m 06.7s +04° 56' 43"
21 6.97 21 Sextantis 10h 14m 08.4s −07° 59' 36"
31 6.98 31 Sextantis 10h 30m 31.0s +02° 09' 01"
20 7.37 20 Sextantis 10h 13m 44.4s −07° 23' 02"
15.6 LHS 292 10h 48m 13s −11° 20' 12" 14.81

Source: The Bright Star Catalogue, 5th Revised Ed., The Hipparcos Catalogue, ESA SP-1200

[edit] See also


Constellations introduced by Johannes Hevelius in the 1690 text Firmamentum Sobiescianum.

Canes Venatici | Lacerta | Leo Minor | Lynx | Scutum | Sextans | Vulpecula

Obsolete Constellations introduced by Johannes Hevelius in the 1690 text Firmamentum Sobiescianum.

Cerberus | Mons Maenalus | Triangulum Minor

[edit] External links

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