Printer-friendly version Share:  Share this page on FacebookShare this page on TwitterShare this page by emailShare this page with other services

Minor Planet Named for John Muir

The International Astronomical Union (IAU), through the Smithsonian Astrophysical Observatory's (SAO) Minor Planet Center (MPC), has announced the naming of a newly discovered minor planet in honor of pioneer conservationist John Muir. The announcement was made in the June 2006 issue of the Minor Planet Circular, published by the SAO/MPC. This development seems an appropriate tribute for someone who gave his address as "Earth-Planet, Universe!"

The tiny, 1-mile diameter celestial body, now named "Johnmuir", was discovered in August 2004 by amateur astronomer R.E. Jones from his backyard observatory located in a Los Angeles suburb. Mr. Jones was making photographic measurements of the position of another small celestial body - a near-Earth asteroid discovered by a professional observatory just the night before - when he noticed a second, much slower moving object in his photographs. A check of catalogues and positions of known objects in the Solar System suggested that the second object was likely a new discovery.
Subsequent observations by the Francisquito Observatory (the name of Mr. Jones' observatory in the Santa Clarita Valley) and by professional observatories including Mt. Palomar in California and Kitt Peak in Arizona confirmed the new find, and Francisquito Observatory was credited by the IAU/MPC with discovery of Solar System object number 2004PX42.

Below: Diagram showing location of Johnmuir, celestial object 2004PX42, with respect to Sun, inner planets and Jupiter on date of discovery.

Orbit of Minor Planet Johnmuir - 2004PX42

[Image courtesy of Francisquito Observatory]

Once 2004PX42 had been observed a sufficient number of times to enable the calculation of a very precise orbit (which occurred in early 2006 following additional measurements by the Kitt Peak Observatory), Mr. Jones was given the opportunity to propose a name for his discovery. The name Johnmuir was submitted to the 15-member Committee on Small Body Nomenclature of the IAU and approved just prior to publication of the SAO/MPC's June 2006 Minor Planet Circular.

In the official citation for the name proposal, John Muir is recognized for his scientific contributions to the fields of glaciology and botany in the late 19th century, and for his tireless promotion of the National Park concept in the early 20th century. John Muir joins a select group of individuals who have had small Solar System objects named in their honor,
including composer Wolfgang Amadeus Mozart, and physicist Albert Einstein.

Discovery Circumstances:

Main Belt asteroid discovered by Francisquito Observatory on 2004.08.11, in second-night images taken to confirm previous Francisquito main belt discovery 2004PC27. Brightness measured at magnitude 20.1 at time of discovery, with a sky motion of 0.30arc-sec/min. Absolute magnitude: 17.2. Distance: 1.158AU. Confirmation observations made on 2004.08.12, provisional designation issued by MPC on same date. Also observed by MIT-LINEAR (Socorro, NM) on 2004.08.11. Later linked with single-night observations by Kitt Peak (Arizona) on 2002.02.06, LPL-Spacewatch (Arizona) on 2002.02.09, LINEAR on 2002.02.11, and Kitt Peak-Spacewatch on 2000.08.01; a previous designation of 2002CK262 had been used for one or more of the single-night observations in 2002. Celestial coordinates: RA 00h 41m 57.35s; DEC +06deg 29m 49.8s.

For more information :

Richard E. Jones

June 12, 2006


John Muir Exhibit

Home | Alphabetical Index | What's New  

Sierra Club® and "Explore, enjoy and protect the planet"® are registered trademarks of the Sierra Club. © 2023 Sierra Club.
The Sierra Club Seal is a registered copyright, service mark, and trademark of the Sierra Club.