2017 TD6

2017 TD₆ is a micro-asteroid, classified as a near-Earth object of the Apollo group, approximately 10–20 meters in diameter. It was first observed by Pan-STARRS at Haleakala Observatory, Hawaii, on 11 October 2017.^[2]

2017 TD₆

Discovery[1][2]
Discovered by	Pan-STARRS
Discovery site	Haleakala Obs.
Discovery date	11 October 2017 (first observed only)
Designations
MPC designation	2017 TD6
Minor planet category	NEO · Apollo[1]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 6
Observation arc	(8 days)
Aphelion	1.5284 AU
Perihelion	0.7798 AU
Semi-major axis	1.1541 AU
Eccentricity	0.3243
Orbital period (sidereal)	1.24 yr (453 days)
Mean anomaly	275.44°
Mean motion	0° 47m 42s / day
Inclination	1.7198°
Longitude of ascending node	26.985°
Argument of perihelion	82.738°
Earth MOID	0.00034 AU · 0.13 LD
Physical characteristics
Dimensions	9.9–22 m[3] 11 m (generic at 0.20)[4]
Absolute magnitude (H)	27.162[1] · 27.175

On 19 October 2017, the asteroid transited Earth at a nominal distance of 191,000 km; 119,000 mi (0.001278 AU), which corresponds to 0.5 lunar distances (LD). On the following day it also passed near the Moon at 113,000 km (0.00075575 AU).^[1] Peaking near a magnitude of 18, the object was too faint to be seen—except for the largest telescopes.^[3]

As of 2018, 2017 TD₆ has a poorly determined orbit with an uncertainty of 6 and a short observation arc of 8 days only. Due to its small size, the asteroid is likely to remain unobserved until its next, still relatively distant approach, predicted to occur in March 2044, at a distance of 2,030,000 km (0.01358 AU) or 5.3 LD from Earth.^[1]

See also

• 2012 TC4 – A similar small asteroid that passed close to the earth on 12 October 2017