- There are three Donati comets: C/1855 L1 (a.k.a. 1855 II), C/1858 L1 (this one), and C/1864 R1 (a.k.a. 1864 I).
|Discovered by||Giovanni Battista Donati|
|Orbital characteristics A|
|Semi-major axis||~147 AU|
|Orbital period||~1,739 yr|
|Last perihelion||September 30, 1858|
Comet Donati, or Donati's Comet, formally designated C/1858 L1 and 1858 VI, is a long-period comet named after the Italian astronomer Giovanni Battista Donati who first observed it on June 2, 1858. After the Great Comet of 1811, it was the most brilliant comet that appeared in the 19th century. It was also the first comet to be photographed. It was nearest the Earth on October 10, 1858. The comet has an orbital inclination of 116.9°.
Abraham Lincoln, then a candidate for a seat in the U.S. Senate, sat up on the porch of his hotel in Jonesboro, Illinois, to see "Donti's Comet" on September 14, 1858, the night before the third of his historic debates with Stephen Douglas. Donati's Comet appears as a streak and star in the early evening sky of a painting by William Dyce, Pegwell Bay, Kent – a Recollection of October 5th 1858.
Due to its long elliptical orbit, it is estimated that Donati's Comet will not be seen passing by Earth again until the 4th millennium.
The comet was photographed on September 28, 1858, at Harvard College Observatory by George P. Bond, son of William C. Bond, director of the observatory. He made several attempts with increasing exposure times, finally achieving a discernible image. He later wrote, "only the nucleus and a little nebulosity 15" in diameter acted on the plate in an exposure of six minutes".
- C/1857 V1 (a.k.a. 1857 VI), Comet Donati-van Arsdale
- C/1864 O1 (a.k.a. 1864 III), Comet Donati-Toussaint
- Horizons output. "Barycentric Osculating Orbital Elements for Comet C/1858 L1 (Donati)". Retrieved 2011-02-03. (Solution using the Solar System Barycenter and barycentric coordinates. Select Ephemeris Type:Elements and Center:@0)
- "JPL Small-Body Database Browser: C/1858 L1 (Donati)" (1859-03-04 last obs). Jet Propulsion Laboratory. Retrieved 2011-05-15.
- Page 273, White, Ronald C. Jr., 2009. A. Lincoln: A Biography, first edition. New York: Random House. 796 pages.
- Rothstein, Edward. Darwin's wake splashed artists, too. March 2, 2009. Exhibition review, New York Times, accessed March 4, 2009.
- The Earliest Comet Photographs, SAO/NASA Astrophysics Data System, retrieved August 17, 2013