Donald Edward Machholz (October 7, 1952 – August 9, 2022) was an American amateur

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, natural satellite, moons, comets and galaxy, g ...

who was credited with the discovery of 12

comet A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena ar ...

s that bear his name.

Personal life and death

In 2014, he married

photojournalist Photojournalism is journalism that uses images to tell a news story. It usually only refers to still images, but can also refer to video used in broadcast journalism. Photojournalism is distinguished from other close branches of photography (such ...

Michele Machholz. They resided at the Stargazer Ranch in

Wikieup, Arizona Wikieup is an unincorporated community and census-designated place (CDP) located on U.S. Route 93 in Mohave County, Arizona, United States. It is located approximately northwest of Phoenix and southeast of Las Vegas. As of the 2020 census, th ...

. Machholz died in the early morning of August 9, 2022, at his home in

, from complications of

COVID-19 Coronavirus disease 2019 (COVID-19) is a contagious disease caused by a virus, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The first known case was COVID-19 pandemic in Hubei, identified in Wuhan, China, in December ...

. His obituary at ''

Astronomy Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...

'' stated, "In the years leading up to his death, Machholz was considered the most prolific visual comet discoverer alive."

Career

He spent more than 9,000 hours comet hunting in a career spanning over 50 years. These comets include the periodic comets

96P/Machholz Comet 96P/Machholz or 96P/Machholz 1 is a Short-period comet, short-period sungrazing comet discovered on May 12, 1986, by Amateur astronomy, amateur astronomer Donald Machholz on Loma Prieta peak, in central California using binoculars. On June ...

, 141P/Machholz, the non-periodic C/2004 Q2 (Machholz) that were visible with binoculars in the northern sky in 2004 and 2005, C/2010 F4 (Machholz), and C/2018 V1 (Machholz-Fujikawa-Iwamoto) In 1985, comet Machholz 1985-e, was discovered using a homemade cardboard telescope with a wide aperture, 10 inches across, that gave it a broader field of view than most commercial telescopes. Machholz utilized a variety of methods in his comet discoveries, in 1986 using 29×130 binoculars he discovered

. Machholz was one of the inventors of the

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 co ...

, which is a race to observe all the

Messier object The Messier objects are a set of 110 astronomical objects catalogued by the French astronomer Charles Messier in his ''Catalogue des Nébuleuses et des Amas d'Étoiles'' (''Catalogue of Nebulae and Star Clusters''). Because Messier was only int ...

s in a single night. Asteroid 245983 Machholz, discovered by Kazimieras Černis, was named in honor of Machholz in November 2017.

Comets discovered

* 1978 Comet Machholz (1978l) * 1985 Comet Machholz (1985e) * 1986 Comet

* 1988 Comet Machholz (1988j) * 1992 Comet Tanaka-Machholz (1992d) * 1992 Comet Machholz (1992k) * 1994 Comet Nakamura-Nishimura-Machholz (1994m) * 1994 Comet 141P/Machholz 2 * 1994 Comet Machholz 1994r * 2004 Comet Machholz (C/2004 Q2) * 2010 Comet Machholz C/2010 F4 * 2018 C/2018 V1 (Machholz-Fujikawa-Iwamoto)

Awards and honors

* 1978 Tuthill Comet Award Roger Tuthill for discovering Comet Machholz (1978L) * 1985 Tuthill Comet Award Roger Tuthill for discovering Comet Machholz (1986e) * 1986 Tuthill Comet Award Roger Tuthill for discovering Periodic Comet Machholz 1 (1986e) * 1994

Walter H. Haas Walter H. Haas (July 3, 1917 – April 6, 2015) was an American amateur astronomy, amateur astronomer. He started observational astronomy, observing in the 1930s. After the Second World War he founded the Association of Lunar and Planetary Observer ...

Award Association of Lunar and Planetary Observers * 1995 Machholz was the recipient of the G. Bruce Blair Medal * 2000 Peggy Haas Service Award Association of Lunar and Planetary Observers Service to

Association of Lunar and Planetary Observers The Association of Lunar and Planetary Observers (ALPO or A.L.P.O.) is an international scientific and educational organization established in March 1947 in the United States by Walter H. Haas, and later incorporated in 1990. ALPO is an organizati ...

* 2005

Edgar Wilson Award __NOTOC__ The Edgar Wilson Award is an annual international award established in 1998 consisting of a monetary award and a plaque allocated annually to amateur comet discoverers. It is administered by the Smithsonian Astrophysical Observatory (SAO) ...

Harvard's

Smithsonian Astrophysical Observatory The Smithsonian Astrophysical Observatory (SAO) is a research institute of the Smithsonian Institution, concentrating on astrophysical studies including galactic and extragalactic astronomy, cosmology, solar, earth and planetary sciences, the ...

for discovering Comet Machholz C/2004 Q2 * 2010

Harvard's

for discovering Comet Machholz C/2010 F4 * 2017 Asteroid 245983 Machholz discovered by Kazimieras Černis was named in honor of Donald Machholz in November 2017 * 2018

Harvard's

for discovering Comet C/2018 V1 Machholz-Fujikawa-Iwamoto * 2021 Leslie C. Peltier Award

Astronomical League The Astronomical League is an umbrella organization of amateur astronomy societies. Currently their membership consists of over 280 organizations across the United States, along with a number of Members-at-Large, Patrons, and Supporting members. ...

for the visual discovery of 12 comets and contributions to astronomy

Books

* ''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 A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena are ...

and what to look for''

References

General references

* Associated Press (June 16, 1985
"Amateur Astronomer Nails Down His Second Comet"

Los Angeles Times The ''Los Angeles Times'' (abbreviated as ''LA Times'') is a daily newspaper that started publishing in Los Angeles in 1881. Based in the LA-adjacent suburb of El Segundo since 2018, it is the sixth-largest newspaper by circulation in the Un ...

Retrieved December 29, 2016 * Jet Propulsion Laboratory (October 14, 1994
"MACHHOLZ'S BANNER YEAR"

Jet Propulsion Laboratory The Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center in the City of La Cañada Flintridge, California, United States. Founded in the 1930s by Caltech researchers, JPL is owned by NASA an ...

* Library of Congress (2002
"Machholz, Don 1952–"

Library of Congress The Library of Congress (LOC) is the research library that officially serves the United States Congress and is the ''de facto'' national library of the United States. It is the oldest federal cultural institution in the country. The library is ...

* Joe Rao (September 17, 2004
"Newfound Comet Set for Winter Display"

Space.com Space.com is an online publication focused on space exploration, astronomy, skywatching and entertainment, with editorial teams based in the United States and United Kingdom. The website offers live coverage of space missions, astronomical discov ...

* Debi Drake (May 22, 2005
"Meet The Comet Hunter: Don Machholz"
American Profile

AMG/Parade Parade Media (previously known as AMG/Parade and Athlon Media Group) is a publisher founded in 1967 that is based in Nashville, Tennessee. Nashville's Spencer Hays was its majority stockholder. It was purchased by The Arena Group in 2022 and now ...

* Alan MacRobert (December 2, 2008
"A Very Oddball Comet"

Sky & Telescope ''Sky & Telescope'' (''S&T'') is a monthly American magazine covering all aspects of amateur astronomy, including the following: *current events in astronomy and space exploration; *events in the amateur astronomy community; *reviews of astronomic ...

Retrieved December 2, 2008 * Jeanna Bryner (December 2, 2008
"Odd Comet Possibly from Another Star System"

* Roger W. Sinnott (March 27, 2010
"New Comet Machholz"

Retrieved March 30, 2010. * Brooks Hays (November 3, 2017
"SOHO Spacecraft Spots Comet Machholz 96P, A Return Visitor"

UPI United Press International (UPI) is an American international news agency whose newswires, photo, news film, and audio services provided news material to thousands of newspapers, magazines, radio and television stations for most of the 20th c ...

* Gareth V. Williams (November 11, 2018
"MPEC 2018-V151: COMET C/2018 V1 (Machholz-Fujikawa-Iwamoto)"

Minor Planet Center The Minor Planet Center (MPC) is the official body for observing and reporting on minor planets under the auspices of the International Astronomical Union (IAU). Founded in 1947, it operates at the Smithsonian Astrophysical Observatory. Function ...

. * Bob King (November 9, 2018
"Amateur Don Machholz Discovers His 12th Comet!"

MPEC 2018-V151: COMET C/2018 V1 (Machholz-Fujikawa-Iwamoto)
* Bob King (November 11, 2018
Arizona Amateur Discovers New Dawn Comet — Here’s How To Find It

Comet C/2018 V1 (Machholz-Fujikawa-Iwamoto) Sky Charts and Coordinates

JPL viewer

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...

External links

Don Machholz
* {{DEFAULTSORT:Machholz, Donald 1952 births 2022 deaths Deaths from the COVID-19 pandemic in Arizona Discoverers of comets 20th-century American astronomers People from Mohave County, Arizona 21st-century American astronomers Scientists from Arizona