(153814) 2001 WN5

(153814) 2001 WN₅ is a sub-kilometer asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group.

2028 Earth/Moon approach^[1]

Date & Time	Approach to	Nominal distance	uncertainty region (3-sigma)
2028-Jun-26 05:23	Earth	248714 km	± 25 km[3]
2028-Jun-26 07:43	Moon	502854 km	± 26 km

(153814) 2001 WN₅

Discovery[1]
Discovered by	LONEOS
Discovery site	Anderson Mesa Stn.
Discovery date	20 November 2001
Designations
MPC designation	(153814) 2001 WN5
Alternative designations	2001 WN5
Minor planet category	NEO PHA Apollo[1]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	21.88 yr (7,990 days)
Aphelion	2.5114 AU
Perihelion	0.9125 AU
Semi-major axis	1.7119 AU
Eccentricity	0.4670
Orbital period (sidereal)	2.24 yr (818 days)
Mean anomaly	46.227°
Mean motion	0° 26m 24s / day
Inclination	1.9197°
Longitude of ascending node	277.51°
Argument of perihelion	44.569°
Earth MOID	0.0015 AU (0.6 LD)
Physical characteristics
Mean diameter	0.932±0.011 km[2]
Geometric albedo	0.097±0.016[2]
Absolute magnitude (H)	18.3[1]

Description

Nominal orbit of 2001 WN₅ (green line) passing the Earth–Moon system in June 2028

It was discovered by the Lowell Observatory Near-Earth-Object Search at Anderson Mesa Station on 20 November 2001,^[4] The potentially hazardous asteroid was removed from the Sentry Risk Table on 30 January 2002.^[5]

There are precovery images dating back to 10 February 1996.^[1] The orbit is well determined with an observation arc of 14.9 years which includes two radar delay observations. It has an Uncertainty Parameter of 0.^[1]

The asteroid will pass 248,700 km (0.647 LD) from the Earth on 26 June 2028.^[1] During the close approach, the asteroid should peak at about apparent magnitude 6.7,^[6] and will be visible in binoculars. It has an absolute magnitude (H) of 18.2.^[1]

According to observations by the NEOWISE mission, the asteroid measures approximately 0.9 km in diameter and its surface has a rather low albedo of 0.097.^[2]

History of close approaches of large near-Earth objects since 1908 ^(A)

PHA	Date	Approach distance in lunar distances			Abs. mag (H)	Diameter (C) (m)	Ref (D)
		Nominal(B)	Minimum	Maximum
(152680) 1998 KJ9	1914-12-31	0.606	0.604	0.608	19.4	279–900	data
(458732) 2011 MD5	1918-09-17	0.911	0.909	0.913	17.9	556–1795	data
(163132) 2002 CU11	1925-08-30	0.903	0.901	0.905	18.5	443–477	data
69230 Hermes	1937-10-30	1.926	1.926	1.927	17.5	700-900[7]	data
69230 Hermes	1942-04-26	1.651	1.651	1.651	17.5	700-900[7]	data
2017 NM6	1959-07-12	1.89	1.846	1.934	18.8	580–1300	data
(27002) 1998 DV9	1975-01-31	1.762	1.761	1.762	18.1	507–1637	data
2002 NY40	2002-08-18	1.371	1.371	1.371	19.0	335–1082	data
2004 XP14	2006-07-03	1.125	1.125	1.125	19.3	292–942	data
2015 TB145	2015-10-31	1.266	1.266	1.266	20.0	620-690	data
(137108) 1999 AN10	2027-08-07	1.014	1.010	1.019	17.9	556–1793	data
(153814) 2001 WN5	2028-06-26	0.647	0.647	0.647	18.2	921–943	data
99942 Apophis	2029-04-13	0.0981	0.0963	0.1000	19.7	310–340	data
2017 MB1	2072-07-26	1.216	1.215	2.759	18.8	367–1186	data
2011 SM68	2072-10-17	1.875	1.865	1.886	19.6	254–820	data
(163132) 2002 CU11	2080-08-31	1.655	1.654	1.656	18.5	443–477	data
(416801) 1998 MZ	2116-11-26	1.068	1.068	1.069	19.2	305–986	data
(153201) 2000 WO107	2140-12-01	0.634	0.631	0.637	19.3	427–593	data
(276033) 2002 AJ129	2172-02-08	1.783	1.775	1.792	18.7	385–1242	data
(290772) 2005 VC	2198-05-05	1.951	1.791	2.134	17.6	638–2061	data
(A) This list includes near-Earth approaches of less than 2 lunar distances (LD) of objects with H brighter than 20. (B) Nominal geocentric distance from the center of Earth to the center of the object (Earth has a radius of approximately 6,400 km). (C) Diameter: estimated, theoretical mean-diameter based on H and albedo range between X and Y. (D) Reference: data source from the JPL SBDB, with AU converted into LD (1 AU≈390 LD) (E) Color codes:   unobserved at close approach   observed during close approach   upcoming approaches