C/1864 O1 (Donati–Toussaint)

For the other comets discovered by Giovanni Battista Donati, see Comet Donati (disambiguation).

C/1864 O1 (Donati–Toussaint)

Discovery
Discovered by	Giovanni B. Donati Carlo Toussaint
Discovery site	Florence, Italy
Discovery date	23 July 1864
Designations
Alternative designations	1864 III
Orbital characteristics
Epoch	16 October 1864 (JD 2402160.5)
Observation arc	213 days
Number of observations	57
Aphelion	2,900 AU
Perihelion	0.931 AU
Semi-major axis	1,450 AU
Eccentricity	0.999358
Orbital period	55,242 years
Inclination	109.71°
Longitude of ascending node	33.666°
Argument of periapsis	232.46°
Last perihelion	11 October 1864
TJupiter	–0.400
Physical characteristics
Comet total magnitude (M1)	5.2
Apparent magnitude	9.0 (1864 apparition)

Comet Donati–Toussaint, formally designated as C/1864 O1, is a non-periodic comet co-discovered by Italian astronomers, Giovanni Battista Donati and Carlo Toussaint in July 1864.

Discovery and observations

On the night of 23 July 1864, astronomers Giovanni Battista Donati and Carlo Toussaint spotted a new comet within the constellation Coma Berenices. Their discovery was confirmed four days later on July 27. Although it never came close to either the Sun or the Earth to allow itself to become a bright object, astronomers were able to observe it until 25 February 1865, and thus were able to determine its orbit with higher precision.

External links

• C/1864 O1 at the JPL Small-Body Database