Amateur astronomy is a hobby where participants enjoy observing or imaging celestial objects in the sky using the unaided eye, binoculars, or telescopes. Even though scientific research may not be their primary goal, some amateur astronomers make contributions in doing citizen science, such as by monitoring variable stars, double stars, sunspots, or occultations of stars by the Moon or asteroids, or by discovering transient astronomical events, such as comets, galactic novae or supernovae in other galaxies.
Comet Hale–Bopp is a comet that was one of the most widely observed of the 20th century and one of the brightest seen for many decades.
A minor-planet moon is an astronomical object that orbits a minor planet as its natural satellite. As of January 2022, there are 457 minor planets known or suspected to have moons. Discoveries of minor-planet moons are important because the determination of their orbits provides estimates on the mass and density of the primary, allowing insights into their physical properties that are generally not otherwise accessible.
In ancient times, only the Sun and Moon, a few stars, and the most easily visible planets had names. Over the last few hundred years, the number of identified astronomical objects has risen from hundreds to over a billion, and more are discovered every year. Astronomers need to be able to assign systematic designations to unambiguously identify all of these objects, and at the same time give names to the most interesting objects, and where relevant, features of those objects.
Comet Elst–Pizarro is a body that displays characteristics of both asteroids and comets, and is the prototype of active asteroids. Its orbit keeps it within the asteroid belt, yet it displayed a dust tail like a comet while near perihelion in 1996, 2001, and 2007.
Brian Geoffrey Marsden was a British astronomer and the longtime director of the Minor Planet Center (MPC) at the Center for Astrophysics | Harvard & Smithsonian.
Takao Kobayashi is a Japanese amateur astronomer and an outstanding discoverer of minor planets who currently works at the Ōizumi Observatory. The asteroid 3500 Kobayashi is named after him.
Pierre Antonini is a retired French mathematics professor and amateur astronomer who has discovered several minor planets and two supernovae at his private Observatoire de Bédoin located at Bédoin, southeastern France. For many of his discoveries he used a 16-cm telescope or a 30-cm telescope.
Thomas Joel Bopp was an American amateur astronomer. In 1995, he discovered comet Hale–Bopp; Alan Hale discovered it independently at almost the same time, and it was thus named after both of them. At the time of the comet discovery he was a manager at a construction materials factory and an amateur astronomer. On the night of July 22, Bopp was observing the sky with friends in the Arizona desert when he made the discovery. It was the first comet he had observed and he was using a borrowed, home-built telescope.
Comet Boethin was a periodic Jupiter-family comet discovered in 1975 by Leo Boethin. It appeared again in January 1986 as expected. Although the comet was next expected at perihelion in April 1997, no observations were reported, and the comet is thought to have disintegrated. It has not been observed since March 1986. The comet might have come to perihelion in late July 2020, but the uncertainty in the comet's position is hundreds of millions of km. The old orbit would have the comet next coming to perihelion around November 2031.
The International Astronomical Union Circulars (IAUCs) are notices that give information about astronomical phenomena. IAUCs are issued by the International Astronomical Union's Central Bureau for Astronomical Telegrams (CBAT) at irregular intervals for the discovery and follow-up information regarding such objects as planetary satellites, novae, supernovae, and comets.
167P/CINEOS (P/2004 PY42) is a large periodic comet and active, grey centaur, approximately 66 kilometers (41 miles) in diameter, orbiting the Sun outside the orbit of Saturn in the Solar System. It was discovered on August 10, 2004, by astronomers with the CINEOS survey at Gran Sasso in Italy. It is one of only a handful known Chiron-type comets.
A minor planet is "lost" when today's observers cannot find it, because its location is too uncertain to target observations. This happens if the orbital elements of a minor planet are not known accurately enough, typically because the observation arc for the object is too short, or too few observations were made before the object became unobservable.
Leonid Vladimirovich Elenin is a Russian amateur astronomer working with the ISON-NM observatory (H15) via the International Scientific Optical Network (ISON), which is the first Russian remote observatory in the West.
(196256) 2003 EH1 is an asteroid, classified as near-Earth object of the Amor group. It was discovered on 6 March 2003, by astronomers of the LONEOS program at Anderson Mesa Station near Flagstaff, Arizona, in the United States. Peter Jenniskens (2003–2004) proposed that it is the parent body of the Quadrantid meteor shower. 2003 EH1 is likely an extinct comet and may even be related to the comet C/1490 Y1. 2003 EH1 came to perihelion on 12 March 2014.
Comet Swift–Tuttle is a large periodic comet with a 1995 (osculating) orbital period of 133 years that is in a 1:11 orbital resonance with Jupiter. It fits the classical definition of a Halley-type comet, which has an orbital period between 20 and 200 years. The comet was independently discovered by Lewis Swift on July 16, 1862 and by Horace Parnell Tuttle on July 19, 1862.
163P/NEAT is a periodic comet discovered on November 5, 2004 by Near-Earth Asteroid Tracking (NEAT) using the 1.2 meter Samuel Oschin telescope at Palomar Observatory.
246P/NEAT is a periodic comet discovered on 2004 March 28 by Near-Earth Asteroid Tracking (NEAT) using the 1.2-metre (47 in) reflector at Haleakala. It was given the permanent number 246P on 2011 January 14.
Michel Ory is a Swiss amateur astronomer and a prolific discoverer of minor planets and comets.
Tenagra Observatory and Tenagra Observatory II are astronomical observatories in Cottage Grove, Oregon and Arizona. The observatories house heavily automated robotic telescopes.
