Robert Scott McMillan is an American astronomer and retired research professor affiliated with the

Lunar and Planetary Laboratory The Lunar and Planetary Laboratory (LPL) is a research center for planetary science located in Tucson, Arizona. It is also a graduate school, constituting the Department of Planetary Sciences at the University of Arizona. LPL is one of the wor ...

(LPL) at the

University of Arizona The University of Arizona (Arizona, U of A, UArizona, or UA) is a Public university, public Land-grant university, land-grant research university in Tucson, Arizona, United States. Founded in 1885 by the 13th Arizona Territorial Legislature, it ...

. He is known for his work in studying

minor planets According to the International Astronomical Union (IAU), a minor planet is an astronomical object in direct orbit around the Sun that is exclusively classified as neither a planet nor a comet. Before 2006, the IAU officially used the term ''minor ...

, stellar radial velocities, and astronomical instrumentation. McMillan served as the Principal Investigator of the

Spacewatch The Spacewatch Project is an astronomical survey that specializes in the study of minor planets, including various types of asteroids and comets at University of Arizona telescopes on Kitt Peak near Tucson, Arizona. The Spacewatch Project has be ...

Project, a program dedicated to surveying and tracking small bodies in the

solar system The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Sola ...

. He has made various discoveries, including notably

20000 Varuna 20000 Varuna (provisional designation ) is a large trans-Neptunian object in the Kuiper belt. It was discovered in November 2000 by American astronomer Robert McMillan during a Spacewatch survey at the Kitt Peak National Observatory. It is na ...

.Dr. Robert S. McMillan bio at Lunar and Planetary Lab University of Arizona
On October 19, 2008, he discovered a short-periodic comet 208P/McMillan.

Education and career

McMillan earned a Bachelor of Science degree in Astronomy with High Honors from the

Case Institute of Technology Case Western Reserve University (CWRU) is a Private university, private research university in Cleveland, Ohio, United States. It was established in 1967 by a merger between Western Reserve University and the Case Institute of Technology. Case ...

in June 1972. His senior thesis, titled ''Absolute Magnitudes Determined from the Catalogue of Bright Stars'', marked the beginning of his scholarly engagement with stellar properties.https://www.lpl.arizona.edu/sites/default/files/resources/faculty/cv/McMillan.pdf Abbreviated Biographical Sketch of Robert Scott McMillan 2015 Aug 18 He continued his academic career at the

University of Texas at Austin The University of Texas at Austin (UT Austin, UT, or Texas) is a public university, public research university in Austin, Texas, United States. Founded in 1883, it is the flagship institution of the University of Texas System. With 53,082 stud ...

, where he received a Master of Arts degree in Astronomy in 1974. His master's thesis, ''Intracluster Dust and the Wavelength Dependence of Interstellar Polarization'', focused on the physical properties of cosmic dust within galaxy clusters. McMillan completed his Ph.D. in Astronomy at the

University of Texas The University of Texas at Austin (UT Austin, UT, or Texas) is a public research university in Austin, Texas, United States. Founded in 1883, it is the flagship institution of the University of Texas System. With 53,082 students as of fall 2 ...

in December 1977. His doctoral dissertation, ''New Constraints on the Composition of Interstellar Grains from Observations of Extinction and Polarization'', provided important insights into the nature and behavior of interstellar dust. McMillan has served as a Co-Investigator on

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 ...

’s

Wide-field Infrared Survey Explorer Wide-field Infrared Survey Explorer (WISE, List of observatory codes, observatory code C51, Explorer 92 and MIDEX-6) was a NASA infrared astronomy Space observatory, space telescope in the Explorers Program launched in December 2009.. . WISE L ...

(WISE) and its extended mission, NEOWISE, both of which have played critical roles in surveying the sky in infrared wavelengths and detecting near-Earth objects. His work has contributed to improving the understanding of

asteroids An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). As ...

comets 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, an ...

, and other small bodies in the

. He served on NASA’s Task Force for the Scientific Use of the Space Station from 1984 to 1986, and was involved in a proposal effort for an orbiting Astrometric Imaging Telescope aimed at detecting extrasolar planets, a project that spanned from 1984 to 1992. He has been a member of the

American Astronomical Society The American Astronomical Society (AAS, sometimes spoken as "double-A-S") is an American society of professional astronomers and other interested individuals, headquartered in Washington, DC. The primary objective of the AAS is to promote the adv ...

(AAS) since 1971, and is affiliated with its

Division for Planetary Sciences The Division for Planetary Sciences (DPS) is a division within the American Astronomical Society (AAS) devoted to Solar System research. It was founded in 1968. The first organizing committee members were: Edward Anders, Lewis Branscomb, Josep ...

(DPS). McMillan has also been a member of the

International Astronomical Union The International Astronomical Union (IAU; , UAI) is an international non-governmental organization (INGO) with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and developmen ...

(IAU) since 1988, and the International Society for Optics and Photonics (SPIE) since 1984. After four decades of service, McMillan officially retired from the

on June 30, 2019. He remains involved with the

Project and participates in observational work.

Stellar and Planetary Astronomy

At the

, McMillan contributed to developing techniques for measuring stellar radial velocities with high precision. His group was the first to publish stellar Doppler shift measurements with a precision better than ±20 meters per second in a refereed journal. In 2007, McMillan collaborated on a project that utilized a prototype dispersed Fourier Transform Spectrometer with the 2.3-meter Bok Telescope to measure radial velocities of binary stars.

Spacewatch Project

McMillan joined the Spacewatch Project in 1980 as Co-Investigator and Project Scientist under founder

Tom Gehrels Anton M.J. "Tom" Gehrels (February 21, 1925 – July 11, 2011) was a Dutch–American astronomer, Professor of Planetary Sciences, and Astronomer at the University of Arizona, Tucson. Biography Youth and education Gehrels was born at Ha ...

. He played a role in adapting

charge-coupled device A charge-coupled device (CCD) is an integrated circuit containing an array of linked, or coupled, capacitors. Under the control of an external circuit, each capacitor can transfer its electric charge to a neighboring capacitor. CCD sensors are a ...

(CCD) technology for use in asteroid and comet surveys. McMillan became Principal Investigator of the project in 1997. Under his leadership, the project completed significant instrumentation upgrades, including constructing a 1.8-meter telescope (completed in 2002) and automating and re-equipping the 0.9-meter telescope (rebuilt and automated by 2006). A new imaging system added to the 1.8-meter telescope 2011 increased the observation rate and improved measurement precision.

Discoveries

McMillan has made several discoveries of minor bodies in the solar system. He discovered

Trans-Neptunian Object A trans-Neptunian object (TNO), also written transneptunian object, is any minor planet in the Solar System that orbits the Sun at a greater average distance than Neptune, which has an orbital semi-major axis of 30.1 astronomical units (AU). ...

(20000) Varuna in 2000 and the near-Earth asteroid 2005 YU55 in December 2005. The latter made a close approach to Earth in November 2011. He was also part of the team that recovered asteroid 719 Albert, a long-lost object first observed in 1911. In 2000, through orbital calculations by Gareth V. Williams of the Minor Planet Center, the asteroid was confirmed as Albert. In 2008, McMillan discovered comet 208P/McMillan, a short-period comet with an orbital period of 8.1 years. The asteroid 2289 McMillan, discovered in 1960 by

Cornelis Johannes van Houten Cornelis Johannes "Kees" van Houten (18 February 1920 – 24 August 2002) was a Dutch people, Dutch astronomer. Early life and education Born in The Hague, he spent his entire career at Leiden University except for a brief period (1954–1956) as ...

, is named in his honor.

Selected publications

* * * * * * * * * *

References

External links

University of Arizona – Robert S. (Bob) McMillan

UA Science, Lunar and Planetary Laboratory – Bob McMillan
{{DEFAULTSORT:McMillan, Robert S. Discoverers of comets American planetary scientists University of Texas at Austin College of Natural Sciences alumni University of Arizona faculty Discoverers of trans-Neptunian objects Living people Year of birth missing (living people)