Zeta Reticuli

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Zeta Reticuli 1/2
Observation data
Epoch J2000
Constellation
(pronunciation)
Reticulum
Right ascension 03h 17m 46.2s /
03h 18m 12.8s
Declination -62° 34′ 31″ /
-62° 30′ 22.9″
Apparent magnitude (V) 5.54/5.24
Characteristics
Spectral type G2.5 V/G1 V
U-B color index 0.07/0.01
B-V color index 0.63/0.59
Variable type None
Astrometry
Radial velocity (Rv) +12.2 km/s
Proper motion (μ) RA: 1,337.73/1,331.01 mas/yr
Dec.: 648.84/646.97 mas/yr
Parallax (π) 82.51/82.79 ± 0.54/0.53 mas
Distance 39.51/39.38 ly (12.12/12.08 pc)
Absolute magnitude (MV) 5.12/4.83
Details
Mass 0.93/0.99 M
Radius 0.91/0.99 R
Luminosity 0.79/1.02 L
Temperature 5720/5840 K
Metallicity 0.6/0.6
Rotation ?
Age 8 × 109 years
Other designations
Gl 136/138, HR 1066/1010, CD -63°217/-62°265, HD 20766/20807, LHS 171/172, LTT 1573/1576, GCTP 701.00/705.00, SAO 248770/248774, LFT 275/276, HIP 15330/15371.

Zeta Reticuli (ζ Ret / ζ Reticuli) is a binary star system located about 39 light years away from Earth. It is located in the constellation Reticulum, and is visible to the unaided eye under very dark skies. Because of the southerly location of the system, it is not visible north of the tropics.

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[edit] Characteristics

Originally thought to be old galactic halo Population II subdwarfs, the two stars are now thought to be younger galactic disk stars, but still considerably older than the Sun, perhaps as much as 8 billion years old. They belong to the Zeta Herculis Moving Group. Both stars share similar proper motions and distances confirming that they indeed form a wide binary star. The stars are approximately 9,000 AU apart. The stars revolve around each other once in over a million years. If the skies are dark enough for both stars to be visible, the stars are far enough apart to appear as a close pair of separate stars to the naked eye.

The stars, designated ζ1 Reticuli and ζ2 Reticuli, are both yellow dwarf (main sequence) stars remarkably similar to our Sun. No close-in giant planets have been detected around either of the components, making Earth-like terrestrial planets possible. However, the stars are only 60% as enriched with metals as the Sun. Small, terrestrial planets around less metal-rich stars are less likely according to our current knowledge.

ζ1 Reticuli is slightly less massive and luminous than the Sun. Spectral class of the star is G2.5 V.

ζ2 Reticuli has a very similar mass and luminosity to our Sun. The spectral type of the star is G1 V.

On September 20, 1996 a tentative discovery of a Hot Jupiter around ζ2 was reported, but the discovery was quickly retracted as the signal was shown to be caused by pulsations of the star.

[edit] Zeta Reticuli in ufology

Map of Zeta Reticuli, according to Betty Hill and Marjorie Fish.
Map of Zeta Reticuli, according to Betty Hill and Marjorie Fish.

The Zeta Reticuli system has gained some notoriety in ufology: some ufologists allege that Zeta Reticuli is home to an alien civilization they refer to as the Greys. This is based on the alleged 1961 abduction of Betty and Barney Hill. In 1964, under hypnosis, Betty Hill drew a map she claimed she was shown during the abduction, showing the aliens' home star, the Sun, and 14 other stars. UFO researcher Marjorie Fish constructed a 3-dimensional map of nearby sun-like stars and claimed a good match from the perspective of Zeta Reticuli. The fit of the Hill/Fish star maps was debated in the December 1974 edition of Astronomy Magazine [1][2]. In his Cosmos television program, Carl Sagan debunked the map, noting that the match was not (and could not be expected to be) perfect, and random chance would produce at least one similarly good match to the map somewhere in the star catalog Fish used in her analysis.

In an interview with George Knapp for a television documentary, Bob Lazar, the man who first claimed that Area 51 was a secret UFO research facility, suggested that the UFO that he claimed to have helped reverse-engineer may have come from the vicinity of Zeta Reticuli, or that this information may have been given to him in an attempt to misguide him.

In 2005, several anonymous messages posted to ufology forums claimed that a planet in the Zeta Reticuli system was the site of a United States military project, allegedly named Project Serpo.

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[edit] Astronomical links