17473 Freddiemercury

17473 Freddiemercury (provisional designation 1991 FM₃) is a stony Massalian asteroid from the inner regions asteroid belt, approximately 3.4 kilometers in diameter. The asteroid was discovered on 21 March 1991, by Belgian astronomer Henri Debehogne at ESO's La Silla Observatory in northern Chile, and later named in memory of Freddie Mercury.^[2]

17473 Freddiemercury

Discovery[1]
Discovered by	H. Debehogne
Discovery site	La Silla Obs.
Discovery date	21 March 1991
Designations
MPC designation	(17473) Freddiemercury
Named after	Freddie Mercury (British musician)[2]
Alternative designations	1991 FM3 · 1982 VC9 1999 JE127
Minor planet category	main-belt · (inner) Massalia[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	34.48 yr (12,593 days)
Aphelion	2.7627 AU
Perihelion	2.0180 AU
Semi-major axis	2.3903 AU
Eccentricity	0.1558
Orbital period (sidereal)	3.70 yr (1,350 days)
Mean anomaly	112.26°
Mean motion	0° 16m 0.12s / day
Inclination	0.9109°
Longitude of ascending node	0.8510°
Argument of perihelion	100.59°
Physical characteristics
Dimensions	3.435±0.374 km[1][4]
Geometric albedo	0.313±0.064[1][4]
Absolute magnitude (H)	14.4[1]

Classification and orbit

Freddiemercury is a member of the Massalia family (404),^[3] a large family of stony S-type asteroids with low inclinations in the inner main belt. It orbits the Sun at a distance of 2.0–2.8 AU once every 3 years and 8 months (1,350 days). Its orbit has an eccentricity of 0.16 and an inclination of 1° with respect to the ecliptic.^[1]

The body's observation arc begins 9 years prior to its official discovery observation, with its identification as 1982 VC₉ at Crimea–Nauchnij in November 1982.^[2]

Physical characteristics

According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Freddiemercury measures 3.4 kilometers in diameter and its surface has a high albedo of 0.313.^[4]

As of 2017, the asteroid's exact composition, as well as its rotation period and shape remain unknown.^[1][5]

Naming

On 4 September 2016, one day before what would have been Freddie Mercury's 70th birthday, the International Astronomical Union and the Minor Planet Center named the asteroid after Mercury, as it was discovered the same year as Mercury's death, (M.P.C. 101215)^[6] and its provisional designation included his initials, FM. The approved naming was announced by Mercury's Queen bandmate Brian May at Montreux Casino to mark Mercury's 70th birthday.^[7][8]