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History


MARCH 29, 1807: The German astronomer Heinrich Olbers discovers the asteroid now known as (4) Vesta, the brightest and second-largest asteroid in the main asteroid belt. Vesta was orbited by the Dawn spacecraft between July 2011 and September 2012. It and the other first-known main-belt asteroids are discussed in the Week 1 “Special Topics” presentation.  …

MARCH 22, 2016: The tiny Comet PANSTARRS P/2016 BA14 passes just 0.024 AU from Earth, the closest known cometary approach to Earth thus far in the 21st Century and the third-closest known cometary approach to Earth in history. Despite its closeness, it was never brighter than 13th magnitude. This and other close comet approaches to …

lunar meteorite close-up image

MARCH 15, 2020: Comet ATLAS C/2019 Y1 will pass through perihelion at a heliocentric distance of 0.838 AU. This is the fourth known member of a “group” of comets, the first of which appeared in 1988; this, and other comet “groups,” are discussed in a future “Special Topics” presentation. Comet ATLAS has become bright enough …

MARCH 8, 1772: A French amateur astronomer, Jacques Montaigne, discovers a comet that is followed for one month and that reaches 7th magnitude. Over the next 5½ decades the comet is discovered on two subsequent returns, the latter of these being in 1826 by an Austrian army officer, Wilhelm von Biela, for whom it was …

MARCH 1, 1705: British astronomer Edmond Halley publishes his calculations of the orbits of the comets of 1531, 1607, and 1682, concluding that they are individual returns of the same comet, and that that comet would return in 1758. His prediction turned out to be correct, and the comet has been named in his honor. …

FEBRUARY 23, 1988: David Levy obtains the final visual observation of Comet 1P/Halley during its 1986 return, using the 1.5-meter telescope at Catalina Observatory in Arizona. The comet was located 8.0 AU from the sun and appeared at 17th magnitude.  FEBRUARY 24, 1979: The U.S. Defense Department satellite P78-1 is launched from Vandenberg Air Force …