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© by Zane B. Stein


Dr. Brian Marsden and I had been conducting a dialog about possible Centaur names for the new bodies. I first suggested a list of 17 Centaur names to Dr. Marsden in April 1995, which of course included Nessus. His reply, dated April 28, 1995, included the following response:

"Although the Minor Planet Center has traditionally not done so, the Working Group on Planetary System Nomenclature does operate by compiling a data base of possible names (we have not hitherto done so, mainly because the discoverer has the privilege to propose names, but this may change.) Thus I welcome your list. Resonating Neptunians will be named for "underworld" dieties, the more distant Kuiper Belt population for "creation" dieties."

On May 11 of that year I sent a similar list to Alan Stern at the Chiron Perihelion Campaign.

When I wrote to Dr. Marsden to let him know that several astrologers had independently arrived at the name Nessus for 1993 HA2, he wrote back that it would most likely be officially named in the Spring of 1997, and he would see what he could do about having the name Nessus accepted.

It seems, though, that I was not alone among astrologers in making suggestions to the astronomers. Here is a part of a note I recently received from Robert Von Heeren:

"I have found out that I sent Mr. Jim Scotti our naming recommendation for 1993HA2 on 14. April 1995 at 20h19m UT. Dieter said, he sent a letter with this recommendation to Jim Scotti at 21. April 1995 too. One week later I sent this same recommendation to Mr. Rabinowitz."
Then, on May, 31 1995, Robert sent Dr. Brian Marsden a name-list of 84 Centaurs via e-mail, and recommended to him the Name Nessus for "1993 HA2".

So, as Robert writes,

"The e-mail to Mr. Marsden on 31 May 1995 was actually the third e-mail, but the first "official" recommendation to IAU. Mr. Jim Scotti and Mr. Rabinowitz on the other hand are the discoverers of Pholus and Nessus."

This list of 84 Centaur names is available upon request.

Robert wrote to me about all of this....and I agree completely:

"But really important is: the coincidence or the synchronicity of OUR (three) most simultanous recommendation (and idea) of the SAME name for 1993 HA2."

In April 1997, 1993 HA2 was officially named Nessus.

As far as I know, this is the first time in modern times that astrologers have arrived at the name of a body in the solar system, and their input has resulted in the naming of said body.

This is truly a history-making event.

Robert confirms the exact naming:

"DATE OF OFFICIAL NAMING-PUBLICATION FOR NESSUS FROM MINOR PLANET CENTRE VIA E-MAIL M.P.E.C.-H10, on 4/22/1997, 22h10m UT, Cambridge, USA-MA 71w48, 42n14. (confirmed by Brian D. Marsden) (This puts Nessus is exactly at third cusp!)"
Now, in order to be named, a body's orbit must first be proven rather thoroughly. Then, it is given a minor planet number, and it is only a matter of time after that that it is given its name. For more information on the actual naming process, go to Minor Planet Name Guide

On October 1, 1999, I received word that, on the previous day, two additional Centaurs had been given names: #8405 (1995 GO) has been designated Asbolus, while #10199 (1997 CU26) has been called Chariklo.

Interestingly, the Chariklo and Chiron have not been in conjunction since 1949....and the first time they united that year, on Feb. 13, was at 8 Sagittarius 01. At the time of the above naming, Pluto was 8 Sagittarius 13...and it had been stationary a few weeks earlier at 7 Sagittarius 44.)

The names Chariklo and Asbolus were arrived at by consensus by a group of astrologers that included yours truly. So the history making continued.

On May 14, 2000, acting as spokesperson for the astrologers from the Centaurs and CRP mailing lists, I emailed a suggestion to Dr. Marsden that #10370 (1995 DW2) should be named Hylonome. And on July 27, 2000, the official announcement was made naming #10370 just that. Again, history is made.

Since that time, other Centaurs have been named through proposals sent by members of the astrological community. 1998 SG35 was given the number #52872, and named Okyrhoe. 1998 TF35 was numbered #52975, and named Cyllarus. 1999 UG5 was numbered #31824 and given the name Elatus. 1998 QM107 was given #49036, and named Pelion. 2002 GB10 was numbered #55576 and named Amycus, while 2002 GO9 was numbered #83982, and named Crantor. Most recently, 2000 EC98 was numbered #60558 and given the name Echeclus. (Echeclus has also showed a little bit of cometary behavior, yet no decision has been made to redesignate it a comet. It therefore stands in the same category as Chiron as a comet with centaur status.) There are many more yet to be named, and as they are numbered, they will get their names.

Some other possible proposed names:

1994 TA = Pylenor. This one has been studied quite extensively, and Pylenor seems like the best name for it.
1999 HD12 = Eurytus
#523731 (2014 OK394) = Helops
#33128 (1998 BU48) = Nastor
#44594 (1999 OX3) = Hylaeus

If you have Centaur name suggestions for these bodies, please e-mail me at, and include your reasons. Who may help name a celestial body!

Robert uses these symbols for Pholus and Nessus:
alternate glyphs for Pholus and Nessus

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