Regor

Authors: Eric Mamajek, Susanne M Hoffmann, Youla Azkarrula

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Regor was a name from the space age attached to the bright star Gamma Velorum (alternatively designated Gamma-2 Velorum or abbreviated gam02 Vel).

Etymology and History

Regor was one of three mysterious new names that started appearing around 1967 on American navigational star charts early in the history of the NASA Apollo crewed lunar missions.

The name comes from the first name backwards of Roger Chaffee, Astronaut and Pilot on what was to be the first crewed Apollo-Saturn flight, AS-204. Chaffee and two other astronauts, Gus Grissom and Ed White II, perished in a fire in the Apollo capsule during a launch rehearsal test on January 27, 1967. Their spacecraft, posthumously designated by NASA as Apollo 1, was supposed to launch in February 1967 to conduct the first test flight of the Apollo Command and Service Module (CSM). The star names Regor, Navi, and Dnoces -- backwards for "Roger" (Roger Chaffee), "Ivan" (Virgil Ivan "Gus" Grissom), and "Second" (Edward Higgins White II, i.e. the second) -- started appearing on Apollo navigational star charts in 1967 for the stars designated gamma Velorum, gamma Cassiopeiae, and iota Ursa Majoris, respectively, and subsequently diffusing to popular astronomy works in the late 20th century.

The origin of the names has been controversial. The most extensive publicly available notes exploring the origins of the names and the parties involved appear to be those documented at the Apollo 15 Lunar Surface Journal: Post-Landing Activities site (Eric M. Jones, 1996, last revised 2026) and a 2016 memo written by Apollo 15 Commander David R. Scott for the Lunar Surface Journals. Astronaut David R. Scott (Gemini 8, Apollo 9, Apollo 15) states:

"Unfortunately, as a result of these incorrect entries in the Journal, the origin of Navi, Dnoces, and Regor as a joke has been widely distributed in all forms of information on Apollo. The origin of these names was not a joke; the origin was intended to honor and memorialize three wonderful men who worked so hard to make Apollo a success and eventually gave all they had. Dr. Cleminshaw himself recognized this as an honor in his 1977 book, The Beginners Guide to the Skies:

“Navi (Gamma Cassiopeiae) is “Ivan” spelled backwards and was named in honor of Virgil Ivan Grissom, one of the three astronauts killed in the Apollo fire.” (Note: “in honor of…Grissom”, not “by…..Grissom”). (Similar entries are included for Ed White and Roger Chaffee.)"

Some sources, including Wikipedia, have mistakenly attributed the naming by the Apollo 1 (AS-204) astronauts themselves before their deaths. The origin appears to be the 1988 book Schirra's Space by R. Billings. Astronaut David Scott documents several pieces of evidence in his 2016 memo, first-hand accounts, timing of events, etc. that the Apollo 1 astronauts themselves could not have named them for themselves.

"Among many other factors, I was Gus’s [Virgil Ivan "Gus" Grissom] backup navigator for the first seven months during this period [March-October 1966]; I worked with him [Grissom] almost daily; I flew with him many times, including at night discussing the brilliant stars overhead; and he never said a word about these names. Neither did any of our other four crewmates (Ed [Edward H. White II], Roger [Chaffee], Jim [McDivitt] and Rusty [Schweickart]) ever even hint at new star names."

Astronaut David Scott constrains the likely timing of the naming to March-April 1967, shortly after the January 1967 Apollo 1 fire. David Scott claims that it was the Apollo 9 crew (who were backup crew to Apollo 1) and Dr. Clarence Cleminshaw of Griffith Observatory, who originated the names:

"During the Apollo program, the crews were required to to identify and locate 36 stars for celestial navigation. Most of these stars had popular names, but, at the beginning of Apollo, three did not. Soon after the tragic Apollo 1 fire (about 2 months), the Apollo 9 crew (Jim McDivitt, Dave Scott, and Rusty Schweickart) [who were backup crew for Apollo 1] were undergoing navigation star training in the Griffith Planetarium under the tutelage of Dr. Clarence Cleminshaw, the Director of the Griffith. During a break in Dr. Cs office, we began discussing the fire and the sad loss of the A-1 crew. Somebody (?) suggested that perhaps we should honor the crew and memorialize them by naming the three obscure Apollo navigation stars after them. But how to do that discretely and uniquely? A subsequent comment suggested that we reverse the order of letters in their name - but how? The group then explored several options and decided to use Gus’s middle name (Ivan, or Navi), Ed’s name title (Second, or Denoces), and Roger’s first name (Roger, or Regor). We recorded those in our informal notes and began to use them. Subsequently, they were recorded in the official NASA star list and became the names of preference in all NASA documentation. And I remember just how we arrived at the star names. First we wrote all three full names backwards. Then looking at them, the better sounding name was selected. Virgil Ivan Grissom – Ligriv Navi Mossirg, Edward H. White, Second – Drawde H. Etihw, Dnoces; and Roger B. Chaffee – Regor B. Eeffahc."

One might speculate that as a planetarium director, Cleminshaw would no doubt have been familiar with the infamous case of onomastic subterfuge with the reversed Palermo star names in the constellation Delphinus (Sualocin, Rotanev), which were commonly referenced in popular astronomy books of the era (e.g. Star Lore of All Ages (1911), Star Names: Their Lore and Meaning (1899, 1963)).

In The Griffith Observer edition of September 1967, Griffith Planetarium director Clarence Cleminshaw mentioned the names Navi, Dnoces, and Regor for those three stars in a story on navigational stars. David Scott states that the Apollo 1 crew would not have trained with Cleminshaw in 1966 as Cleminshaw and Griffith Planetarium did not get a contract to train Apollo astronauts for star navigation until September 1966. The Apollo 1 astronauts left California to train at Kennedy Space Center in Florida in early September 1966, shortly after the AS-204 / CM-012 / Apollo 1 spacecraft was shipped (August 1966). David Scott's notebook from mission training in October 1966 listed three bright navigational stars (gamma Cassiopeiae, iota Ursa Majoris, gamma Velorum) that were the only ones of the 37 lacking common names.

The Apollo 1 fire was a great national tragedy in the United States, and in the months afterwards there were commemorations of the astronauts for landmarks like schools, parks, streets, etc. Near the city of Downey, California, home of the North American Aviation plant that designed and built the Apollo Command and Service Modules (CSM), the neighboring city of Long Beach approved on March 21, 1967 the naming of four new artificial islands for four astronauts that had recently died ("Chaffee", "Grissom", "White", and another - "Freeman" for astronaut Ted Freeman, who perished in a flight accident in 1967). David Scott suggests that the idea for the naming may have been influenced by this other commemorative naming in March 1967:

"And this remembrance could very well been influenced by the three islands in Long Beach Harbor that were named in honor of Gus, Ed and Roger soon after the Apollo 1 fire. During the months before the fire [1966], all six of us had spent many hours at the Long Beach Athletic Club and surroundings during our evening leisure activities – Gus, Ed and Roger were good friends of Long Beach too."

The names started appearing in books, catalogs, and star charts in the years afterwards. Some examples include:

• J.W. Rhoads (1971) "Technical Memorandum 33-507: A Reduced Star Catalog Containing 537 Named Stars" (Jet Propulsion Laboratory California Institute of Technology)
• "Edmund Mag 5 Star Atlas" (1975) (Edmund Scientific Co.)
• C.H. Cleminshaw, 1977, "The Beginner's Guide to the Skies : a Month-by-month Handbook for Stargazers and Planet Watchers" (Crowell, New York)
• P. Kunitzsch & T. Smart (1986) "Short Guide to Modern Star Names and Their Derivations" (O. Harrassowitz)
• L. Motz & C. Nathanson (1988) "The Constellations" (Doubleday)
• P. Moore (1990) "The Amateur Astronomer" (Cambridge University Press
• M. R. Chartrand (1991) "The Audubon Society Field Guide to the Night Sky" (A.A. Knopf).
• M. E. Backich (1995) "The Cambridge Guide to the Constellations" (Cambridge University Press).
• P. Moore & W. Tirion (1997) "Cambridge Guide to Stars and Planets" (Cambridge University Press).
• E. Slawik & U. Reichert (1998) "Atlas der Sternbilder ein astronomischer Wegweiser in Photographien".
• R. Godwin, 1999, "Apollo 11" (Apogee Books, Burlington, Ont., Canada)
• H.J.P. Arnold, P. Doherty, P. Moore (1999) "The Photographic Atlas of the Stars" (CRC Press).
• Kostjuk (2002) "HD-DM-GC-HR-HIP-Bayer-Flamsteed Cross Index" http://cdsarc.u-strasbg.fr/viz-bin/Cat?IV/27A.
• M. Rees (2002) "Universe: The Definitive Visual Guide" (DK Publishing).
• P. Moore, 2005, "Firefly Atlas of the Universe"
• S. Dunlop, W. Tirion, A. Rukl, 2005, "Atlas of the Night Sky" (HarperCollins, London)
• J. B. Kaler (2006) "The Cambridge Encyclopedia of Stars", Cambridge University Press.
• J. B. Kaler (2006) "The Hundred Greatest Stars", Springer Science & Business Media.
• P. Kunitzsch & T. Smart (2006) "A Short Guide to 254 Star Names and Their Derivations" (2nd Revised Edition, Sky Publishing, Cambridge MA, USA).
• D.E. Falkner (2011) "The Mythology of the Night Sky" (Springer Science & Business Media).
• R. Dinwiddie, W. Gater, G. Sparrow, C. Stott (2012) "Smithsonian Nature Guide: Stars and Planets" (DK Publishing, New York).
• Driessen et al. 2024, "The Sydney Radio Star Catalogue: Properties of radio stars at megahertz to gigahertz frequencies", Publications of the Astronomical Society of Australia, 41, e084 https://ui.adsabs.harvard.edu/abs/2024PASA...41...84D/abstract

The SIMBAD database includes Regor as the common name for gamma2 Velorum (HD 68273, HR 3207, HIP 39953).

Weblinks

• Website of the IAU WGSN: https://exopla.net/
• Apollo 11 Flown Star Charts (scans courtesy of Larry McGlyn
• The Apollo Lunar Surface Journal and Apollo Flight Journal (NASA), links to Eric M. Jones' Apollo documentation, Apollo Flight Journals (Apollo 7-17), Apollo Lunar Surface Journals (Apollo 11, 12, 14, 15, 16, 17), Navigation Stars used in the AOT (Alignment Optical Telescope)
• REGOR (Gamma-2 Velorum), STARS, Jim Kaler
• SIMBAD page on Regor / gam02 Vel , CDS
• Regor (Gamma Velorum) - entry in "The Beginner's Guide to the Skies: A Month-by-month Handbook for Stargazers and Planet Watchers" by Clarence Higbee Cleminshaw, 1977, Crowell

Reference

• References (general)