Lacerta

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Lacerta
Lacerta
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Abbreviation: Lac
Genitive: Lacertae
Symbology: the Lizard
Right ascension: 22.5 h
Declination: +45°
Area: 201 sq. deg. (68th)
Main stars: 5
Bayer/Flamsteed stars: 16
Stars with known planets: 1
Bright stars: 0
Nearby stars: 0
Brightest star: α Lacertae (3.8m)
Nearest star: α Lacertae (102.4 ly)
Messier objects: 0
Meteor showers:
Bordering constellations: Andromeda
Cassiopeia
Cepheus
Cygnus
Pegasus
Visible at latitudes between +90° and −35°
Best visible at 21:00 (9 p.m.) during the month of October
For the biological genus of lizards, see Lacerta (genus).

Lacerta (IPA: /ləˈsəː(r)tə/, Latin: lizard), is one of the 88 official constellations acknowledged by the International Astronomical Union. It is not among Ptolemy's 48 ancient constellations. Instead it was created ca. 1687 by the astronomer Johannes Hevelius. It doesn't contain any really bright stars, no Messier object, no galaxy brighter than 14.5m, no globular clusters and not a single named star. Correspondingly it is rather difficult to find. The northern part lies on the Milky Way. Lacerta is located between Cygnus, Cassiopeia and Andromeda on the northern celestial sphere. It looks like a 'little Cassiopeia' as it is W shaped as well.

Contents

[edit] Notable features

  • α Lac: this main sequence star of spectral type A1 V has an apparent magnitude of merely 3.77m. There are no other stars brighter than fourth magnitude. α Lac is an optical double star.
  • Roe 47: a multiple star consisting of five components (magnitudes 5.8, 9.8, 10.1, 9.4, 9.8).

[edit] Notable deep sky objects

  • NGC 7243: an open star cluster of approximately 6.4m.
  • BL Lacertae: it was discovered quite early and first thought to be a star and therefore given a variable star designation. However, in reality it is represents the core of a galaxy. It lent its name to a whole type of celestial objects, the BL Lacertae objects (a subtype of blazar.) The object varies irregularly between magnitudes 14 and 17 over a few days.
  • ADS 16402 is a binary star system in Lacerta, around which orbits a planet with some unusual properties.[1] The Jupiter-sized planet exhibits an unexpectedly low density, about the same as cork. This planet is dubbed HAT P-1

[edit] Mythology

Before Johannes Hevelius adopted the name Lacerta several other names had proposed for this part of the sky, among them Sceptrum et Manus Iustitiae (= Sceptre and the hand of Justice) and Frederick's Honors. Being a modern constellation there is no mythology surrounding Lacerta.

[edit] See also

[edit] External links

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The 88 modern Constellations
Andromeda • Antlia • Apus • Aquarius • Aquila • Ara • Aries • Auriga • Boötes • Caelum • Camelopardalis • Cancer • Canes Venatici • Canis Major • Canis Minor • Capricornus • Carina • Cassiopeia • Centaurus • Cepheus • Cetus • Chamaeleon • Circinus • Columba • Coma Berenices • Corona Australis • Corona Borealis • Corvus • Crater • Crux • Cygnus • Delphinus • Dorado • Draco • Equuleus • Eridanus • Fornax • Gemini • Grus • Hercules • Horologium • Hydra • Hydrus • Indus • Lacerta • Leo • Leo Minor • Lepus • Libra • Lupus • Lynx • Lyra • Mensa • Microscopium • Monoceros • Musca • Norma • Octans • Ophiuchus • Orion • Pavo • Pegasus • Perseus • Phoenix • Pictor • Pisces • Piscis Austrinus • Puppis • Pyxis • Reticulum • Sagitta • Sagittarius • Scorpius • Sculptor • Scutum • Serpens • Sextans • Taurus • Telescopium • Triangulum • Triangulum Australe • Tucana • Ursa Major • Ursa Minor • Vela • Virgo • Volans • Vulpecula