Lacerta
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| List of stars in Lacerta | |
| 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: | 17 |
| Stars known to have planets: | 1 |
| Bright stars: | 0 |
| Nearby stars: | 1 |
| Brightest star: | α Lacertae (3.8m) |
| Nearest star: | EV Lacertae (16.5 ly) |
| Messier objects: | 0 |
| Meteor showers: | |
| Bordering constellations: | Andromeda Cassiopeia Cepheus Cygnus Pegasus |
| Visible at latitudes between +90° and −90° Best visible at 21:00 (9 p.m.) during the month of October |
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- For the biological genus of lizards, see Lacerta (genus).
Lacerta (pronounced /ləˈsɝtə/, 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.
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[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 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 a planet orbits 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.
The same constellation was used by the Chumash as Lizard and is included in multiple stories. This constellation was supposed as one of many constellations encountered as one went to the Land-of-the-Dead.
[edit] Citations
[edit] References
- Ian Ridpath and Wil Tirion (2007). Stars and Planets Guide, Collins, London. ISBN 978-0007251209. Princeton University Press, Princeton. ISBN 978-0691135564.
[edit] External links
- The Deep Photographic Guide to the Constellations: Lacerta
- Star Tales – Lacerta
- Weasner's Mighty ETX Site, GO TO LACERTA (a constellation guide for amateur astronomers)
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