(29075) 1950 DA

(29075) 1950 DA
	Radar image of 1950 DA taken at Arecibo in March 2001, from a distance of 22 LD or 0.052 AU
Discovery
Discovered by	Carl A. Wirtanen
Discovery site	Lick Obs.
Discovery date	23 February 1950
Designations
MPC designation	(29075) 1950 DA
Alternative designations	1950 DA · 2000 YK66 · Object Wirtanen
Minor planet category	NEO · Apollo · PHA · risk listed
Orbital characteristics
	Epoch 17 October 2024 (JD 2460600.5)
	Uncertainty parameter 0
Observation arc	74.87 yr (27,345 d)
Aphelion	2.5614 AU
Perihelion	0.8364 AU
Semi-major axis	1.6989 AU
Eccentricity	0.5077
Orbital period (sidereal)	2.214 yr (809 d)
Mean anomaly	223.31°
Mean motion	0° 26m 42.36s / day
Inclination	12.16°
Longitude of ascending node	356.59°
Argument of perihelion	224.76°
Earth MOID	0.03853 AU (14.9948 LD)
Proper orbital elements
Precession of perihelion	13.655 arcsec / yr
Precession of the ascending node	−35.824 arcsec / yr
Physical characteristics
Dimensions	1.39 km × 1.46 km × 1.07 km
Mean diameter	1.3 km; 1.1 km; 1.25±0.12 km; 2.00±0.20 km;
Mass	>4×1012 kg
Mean density	>3.5 g/cm3
Synodic rotation period	2.12160±0.00004 h
Geometric albedo	0.070; 0.25;
Spectral type	S; B–V = 0.862±0.077; V–R = 0.494±0.069; V–I = 0.816±0.067;
Absolute magnitude (H)	16.83; 17.00; 17.28; 17.2; 17.1;

(29075) 1950 DA (provisional designation 1950 DA) is a risk-listed asteroid, classified as a near-Earth object and potentially hazardous asteroid of the Apollo group, approximately 1.3 kilometers (0.81 miles) in diameter. It once had the highest known probability of impacting Earth. In 2002, it had the highest Palermo scale rating with a value of 0.17 and a probability of 1 in 306 (0.33%) for a possible collision in 2880. Since that time, the estimated risk has been updated several times. In December 2015, the odds of an Earth impact were revised to 1 in 8,300 (0.012%) with a Palermo scale rating of −1.42. As of April 2025, it is listed on the Sentry Risk Table with the highest cumulative Palermo scale rating of −0.92. 1950 DA is not assigned a Torino scale rating, because the 2880 date is over 100 years in the future. As of 29 April 2025, the odds of an Earth impact are 1 in 2,600 (0.039%).