Donald Edward Machholz, born October 7, 1952 in Portsmouth, Virginia

Portsmouth, Virginia

Portsmouth is located in the Hampton Roads metropolitan area of the U.S. Commonwealth of Virginia. As of 2010, the city had a total population of 95,535.The Norfolk Naval Shipyard, often called the Norfolk Navy Yard, is a historic and active U.S...

, is an American amateur astronomer

Astronomer

An astronomer is a scientist who studies celestial bodies such as planets, stars and galaxies.Historically, astronomy was more concerned with the classification and description of phenomena in the sky, while astrophysics attempted to explain these phenomena and the differences between them using...

 from Colfax, California

Colfax, California

Colfax is a city in Placer County, California, at the crossroads of Interstate 80 and State Route 174. It is part of the Sacramento–Arden-Arcade–Roseville Metropolitan Statistical Area. The population was 1,963 at the 2010 census...

.

He is the most successful living visual comet hunter in the United States, being
credited with the discovery of 11 comet

Comet

A comet is an icy small Solar System body that, when close enough to the Sun, displays a visible coma and sometimes also a tail. These phenomena are both due to the effects of solar radiation and the solar wind upon the nucleus of the comet...

s, including the periodic comets 96P/Machholz

96P/Machholz

Comet 96P/Machholz or 96P/Machholz 1 is a short-period comet discovered on May 12, 1986 by amateur astronomer Donald Machholz in Loma Prieta, California. Comet 96P/Machholz will next come to perihelion on July 14, 2012....

, 141P/Machholz, the non-periodic C/2004 Q2 (Machholz) that was easily visible in binoculars in the northern sky in 2004 and 2005, and most recently, C/2010 F4 (Machholz).

Machholz is also considered to be one of the inventors of the Messier marathon

Messier marathon

A Messier marathon is an attempt, usually organized by amateur astronomers, to find as many Messier objects as possible during one night. The Messier catalogue was compiled by French astronomer Charles Messier during the late 18th century and consists of 110 relatively bright deep sky objects...

, which is a race to observe all the Messier object

Messier object

The Messier objects are a set of astronomical objects first listed by French astronomer Charles Messier in 1771. The original motivation of the catalogue was that Messier was a comet hunter, and was frustrated by objects which resembled but were not comets...

s in a single night.

Books by Don Machholz

• The Observing Guide to the Messier Marathon: A Handbook and Atlas
• Decade of Comets: A Study of the 33 Comets Discovered by Amateur Astronomers Between 1975 and 1984
• An observer's guide to comet Hale-Bopp: Making the most of Comet Hale-Bopp : when and where to observe Comet Hale-Bopp and what to look for