1400 Tirela

1400 Tirela
	Modelled shape of Tirela from its lightcurve
Discovery
Discovered by	L. Boyer
Discovery site	Algiers Obs.
Discovery date	17 November 1936
Designations
MPC designation	(1400) Tirela
Named after	Charles Tirel; (discoverer's friend)
Alternative designations	1936 WA · 1930 UQ
Minor planet category	main-belt · (outer); Tirela
Orbital characteristics
	Epoch 4 September 2017 (JD 2458000.5)
	Uncertainty parameter 0
Observation arc	86.96 yr (31,762 days)
Aphelion	3.8513 AU
Perihelion	2.4001 AU
Semi-major axis	3.1257 AU
Eccentricity	0.2322
Orbital period (sidereal)	5.53 yr (2,018 days)
Mean anomaly	316.88°
Mean motion	0° 10m 42.24s / day
Inclination	15.631°
Longitude of ascending node	210.10°
Argument of perihelion	111.65°
Physical characteristics
Mean diameter	14.67±0.62 km; 15.697±0.285 km;
Synodic rotation period	13.356 h
Pole ecliptic latitude	(58.0°, −80.0°) (λ1/β1); (297.0°, −41.0°) (λ2/β2);
Geometric albedo	0.216±0.031; 0.2165±0.0309; 0.227±0.022
Spectral type	C (assumed)
Absolute magnitude (H)	11.3 · 11.4 · 11.50

1400 Tirela (provisional designation 1936 WA) is an asteroid and the parent body of the Tirela family, located in the outer regions of the asteroid belt. It was discovered on 17 November 1936, by French astronomer Louis Boyer at the Algiers Observatory in North Africa. The asteroid has a rotation period of 13.4 hours and measures approximately 16 kilometers (9.9 miles) in diameter. It was named after Charles Tirel, a friend of the discoverer.