Philip D. Nicholson is a Professor of Astronomy at Cornell University

Cornell University

Cornell University is an Ivy League university located in Ithaca, New York, United States. It is a private land-grant university, receiving annual funding from the State of New York for certain educational missions...

 in the Astronomy

Astronomy

Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...

 department specialising in Planetary Science

Planetary science

Planetary science is the scientific study of planets , moons, and planetary systems, in particular those of the Solar System and the processes that form them. It studies objects ranging in size from micrometeoroids to gas giants, aiming to determine their composition, dynamics, formation,...

s. He was part of the team led by Brett J. Gladman

Brett J. Gladman

Brett J. Gladman is a Canadian astronomer and a full professor at the University of British Columbia's Department of Physics and Astronomy in Vancouver, British Columbia. He holds the Canada Research Chair in Planetary Astronomy.-Career:...

 that discovered several moons of Uranus

Uranus

Uranus is the seventh planet from the Sun. It has the third-largest planetary radius and fourth-largest planetary mass in the Solar System. It is named after the ancient Greek deity of the sky Uranus , the father of Cronus and grandfather of Zeus...

 and Saturn

Saturn

Saturn is the sixth planet from the Sun and the second largest planet in the Solar System, after Jupiter. Saturn is named after the Roman god Saturn, equated to the Greek Cronus , the Babylonian Ninurta and the Hindu Shani. Saturn's astronomical symbol represents the Roman god's sickle.Saturn,...

. He has been editor-in-chief of the journal Icarus

Icarus (journal)

Icarus is a premier scientific journal dedicated to the field of planetary science. It is published under the auspices of the American Astronomical Society's Division for Planetary Sciences . The longtime publisher was Academic Press, which is now part of Elsevier...

since 1998.

Career

Nicholson received his Ph.D. from Caltech in 1979. Nicholson's research centers on two main areas: Orbital dynamics in planetary ring systems and infrared observational studies of planets, their satellites, and their rings. His work has included studies of the ring systems

Planetary ring

A planetary ring is a ring of cosmic dust and other small particles orbiting around a planet in a flat disc-shaped region.The most notable planetary rings known in Earth's solar system are those around Saturn, but the other three gas giants of the solar system possess ring systems of their...

 of Saturn, Uranus, and Neptune

Neptune

Neptune is the eighth and farthest planet from the Sun in the Solar System. Named for the Roman god of the sea, it is the fourth-largest planet by diameter and the third largest by mass. Neptune is 17 times the mass of Earth and is slightly more massive than its near-twin Uranus, which is 15 times...

 via Voyager

Voyager program

The Voyager program is a U.S program that launched two unmanned space missions, scientific probes Voyager 1 and Voyager 2. They were launched in 1977 to take advantage of a favorable planetary alignment of the late 1970s...

 observations and ground-based stellar occultations; Earth-based observations with the 5-meter Hale telescope

Hale telescope

The Hale Telescope is a , 3.3 reflecting telescope at the Palomar Observatory in California, named after astronomer George Ellery Hale. With funding from the Rockefeller Foundation, he orchestrated the planning, design, and construction of the observatory, but did not live to see its commissioning...

 at Palomar Observatory

Palomar Observatory

Palomar Observatory is a privately owned observatory located in San Diego County, California, southeast of Pasadena's Mount Wilson Observatory, in the Palomar Mountain Range. At approximately elevation, it is owned and operated by the California Institute of Technology...

 of several small moons of Jupiter

Jupiter

Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...

 and Saturn discovered by the Voyager spacecraft; dynamical investigations of the planetary system around the pulsar PSR 1257 + 12

PSR B1257+12

PSR B1257+12, sometimes abbreviated as PSR 1257+12, is a pulsar located roughly 2000 light-years from the Sun. In 2007, it was confirmed that three extrasolar planets orbit the pulsar.- Pulsar :...

, and of the rotational evolution of natural satellites; and studies of the zodiacal dust bands discovered by the Infrared Astronomical Satellite

IRAS

The Infrared Astronomical Satellite was the first-ever space-based observatory to perform a survey of the entire sky at infrared wavelengths....

 in 1983. Together with colleagues in Canada and at Harvard, he has been involved in the discovery of numerous outer satellites of Uranus, Saturn and Neptune. Nicholson is a member of the Visual Infrared Mapping Spectrometer science team on the NASA/ESA Cassini–Huygens mission to Saturn, and was the leader of a team of Cornell and Caltech astronomers studying the impact of Comet Shoemaker-Levy 9

Comet Shoemaker-Levy 9

Comet Shoemaker–Levy 9 was a comet that broke apart and collided with Jupiter in July 1994, providing the first direct observation of an extraterrestrial collision of solar system objects. This generated a large amount of coverage in the popular media, and the comet was closely observed by...

 into Jupiter in July 1994 using the Hale Telescope. He has served on the Committees on Planetary and Lunar Exploration and on Astronomy and Astrophysics of the National Research Council

United States National Research Council

The National Research Council of the USA is the working arm of the United States National Academies, carrying out most of the studies done in their names.The National Academies include:* National Academy of Sciences...

, time assignment committees for the Kuiper Airborne Observatory

Kuiper Airborne Observatory

The Gerard P. Kuiper Airborne Observatory was a national facility operated by NASA to support research in infrared astronomy. The observation platform was a highly modified C-141A jet transport aircraft with a range of 6,000 nautical miles , capable of conducting research operations up to 48,000...

 and Hubble Space Telescope

Hubble Space Telescope

The Hubble Space Telescope is a space telescope that was carried into orbit by a Space Shuttle in 1990 and remains in operation. A 2.4 meter aperture telescope in low Earth orbit, Hubble's four main instruments observe in the near ultraviolet, visible, and near infrared...

, and scientific advisory committees for Arecibo

Arecibo Observatory

The Arecibo Observatory is a radio telescope near the city of Arecibo in Puerto Rico. It is operated by SRI International under cooperative agreement with the National Science Foundation...

 and IPAC

Infrared Processing and Analysis Center

The Infrared Processing and Analysis Center is the NASA science center responsible for the data processing, analysis, and archiving of NASA's infrared astronomy and astrophysics missions...

. He has coauthored review articles on planetary ring dynamics and on the Uranian and Neptunian ring systems.

External links

• Phil Nicholson's homepage