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 on a specific question or field outside the scope of Earth. Astronomers observe astronomical objects, such as stars, planets, natural satellite, moons, comets and galaxy, galax ...

who was credited with the discovery of 12

comet A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or Coma (cometary), coma surrounding ...

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 (suc ...

Michele Machholz. They resided at the Stargazer Ranch in

Wikieup, Arizona Wikieup is an Unincorporated area, unincorporated community and census-designated place (CDP) located on U.S. Route 93 in Arizona, U.S. Route 93 in Mohave County, Arizona, Mohave County, Arizona, United States. It is located approximately north ...

. 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 the coronavirus SARS-CoV-2. In January 2020, the disease spread worldwide, resulting in the COVID-19 pandemic. The symptoms of COVID‑19 can vary but often include fever ...

. His obituary at ''

Astronomy Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall evolution. Objects of interest includ ...

'' 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 Jun ...

, 141P/Machholz, the non-periodic comets, C/1978 R3 (Machholz), 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, 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 of Nebulae and Star Clusters''). Because Messier was interested only in finding comets, he created a list of th ...

s in a single night. Asteroid 245983 Machholz, discovered by

Kazimieras Černis Kazimieras Černis (born November 11, 1958, Vilnius) is a Lithuanian astronomer and astrophysicist, active member of the IAU, and a prolific discoverer of minor planets and comets. In 2012, he discovered 420356 Praamzius, a trans-Neptunian obje ...

, 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 C/2004 Q2 (Machholz) * 2010 C/2010 F4 (Machholz) * 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 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 organizat ...

* 2005 Edgar Wilson Award Harvard's

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

for discovering Comet Machholz C/2004 Q2 * 2010 Edgar Wilson Award Harvard's

for discovering Comet Machholz C/2010 F4 * 2017 Asteroid 245983 Machholz discovered by

was named in honor of Donald Machholz in November 2017 * 2018 Edgar Wilson Award 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 330 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 warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or coma surrounding the nucleus, and ...

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'' is an American Newspaper#Daily, daily newspaper that began publishing in Los Angeles, California, in 1881. Based in the Greater Los Angeles city of El Segundo, California, El Segundo since 2018, it is the List of new ...

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 centers, federally funded research and development center (FFRDC) in La Cañada Flintridge, California, Crescenta Valley, United States. Founded in 1936 by Cali ...

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

Library of Congress The Library of Congress (LOC) is a research library in Washington, D.C., serving as the library and research service for the United States Congress and the ''de facto'' national library of the United States. It also administers Copyright law o ...

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

Space.com Space.com is an online publication focused on outer space, space exploration, astronomy, skywatching and entertainment, with editorial teams based in the United States and United Kingdom. Launched on July 20, 1999, the website offers live coverag ...

* 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 no ...

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

Sky & Telescope ''Sky & Telescope'' (''S&T'') is a monthly magazine covering all aspects of amateur and professional astronomy, including what to see in the sky tonight and new findings in astronomy. Other topics covered include: *observing guides for planets, ...

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 ce ...

* 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. Funct ...

. * 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 agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...

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