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Designation: 2016 WD7 · NASA id: 3764729
Estimated diameter: 9 – 21 meters
These describe where an object sits in a catalogue, not how dangerous it is. The full ranked list is on the impact risk page.
3 kilotonnes – 127 kilotonnes of TNT
This is not a forecast. Nothing here says this object will arrive, and almost nothing ever does — what is actually assessed, by people with far better data than this page has, is on the impact risk page. This is simply the kinetic energy such a body would carry, worked out from its size and its usual encounter speed.
The range spans a factor of 37, and it cannot be narrowed. Nobody has weighed this object. Its diameter is inferred from how bright it is under an assumed reflectivity, which carries a fixed factor of 2.24 — and because mass goes as the cube of diameter, that alone becomes a factor of 11. Density is then assumed somewhere between 1,500 and 5,000 kg/m³, from a loose rubble pile to dense rock. Quoting a tighter figure would be invented precision.
Megatonnes do not mean what the word suggests here. Most of this energy is spent high in the atmosphere, not on the ground, and the comparison with weapons misleads badly. The Chelyabinsk body released around 440 kilotonnes in 2013 — this same calculation gives it 166 to 904 — and the damage was broken windows across a city, from the shock wave of an airburst some thirty kilometres up. No crater, and nothing that reached the ground intact.
Because the flag has nothing to do with how close it came on the day. NASA marks an object a Potentially Hazardous Asteroid only if both of these are true of its orbit and its size:
The two terms:
AU — astronomical unit, the average Earth–Sun distance, 149,597,871 km. 0.05 AU is about 7.5 million km.
MOID — minimum orbit intersection distance, the closest the two orbits ever come, whatever the timing.
See the glossary for NEO, PHA and H.
So a large rock passing at 39 million km today can be flagged, because on some future orbit it could come far nearer — while a pebble skimming past at 4 million km is not, because it would never reach the ground.
Three objects that all passed Earth on 30 August 2026 make the point better than any definition:
| Object | Size | Orbit’s closest to Earth’s | Missed by, that day | Flagged |
|---|---|---|---|---|
| 2013 JR28 | 122–272 m | 5.3 M km (0.035 AU) | 39.2 M km | Yes — both tests pass |
| 2012 LE11 | 629–1,406 m | 23.3 M km (0.156 AU) | 26.1 M km | No — orbit never gets near enough |
| 2007 EK | 3.7–8.2 m | 198,000 km (0.0013 AU) | 4.2 M km | No — far too small |
The middle one is five times larger than the flagged one and passed closer on the day, but its path can never come within 23 million km of ours. The last one’s orbit crosses inside the Moon’s distance — nearer than any other object here — and it is still not hazardous, because at a few metres across it would burn up long before it landed.
“Potentially hazardous” is a watchlist criterion, not a prediction. None of these is on a collision course; the label means an object is worth keeping precise track of over the coming centuries.
Orbit class: APO — Near-Earth asteroid orbits which cross the Earth’s orbit similar to that of 1862 Apollo
a (semi-major axis) > 1.0 AU; q (perihelion) < 1.017 AU
| Orbital period | 508.9 days (1.39 years) |
| Eccentricity | .2060992274614799 (0 = circular, closer to 1 = more elongated) |
| Semi-major axis | 1.247442709939933 AU |
| Inclination | .6650621056348403° (tilt of its orbit vs. Earth's) |
| Perihelion distance | .9903457311188583 AU (closest approach to the Sun) |
| Aphelion distance | 1.504539688761009 AU (farthest from the Sun) |
| Minimum Orbit Intersection Distance | 0.00981 AU = 1,467,009 km (closest its orbit path ever comes to Earth's, regardless of timing) |
| Ascending node longitude | 41.72940637682611° |
| Argument of perihelion | 44.75049471206145° |
| Mean anomaly / motion | 145.2368611576626° / .7074132009697935°/day |
| Jupiter Tisserand invariant | 5.129 (helps distinguish asteroids from comets) |
| Reference epoch / equinox | JD 2461000.5 / J2000 |
| Orbit determined | 2021-04-15 18:15:11 |
| Observed | 2016-11-24 to 2017-01-01 (38 day arc, 71 observations used) |
| Orbit uncertainty | 4 (0 = best known, 9 = least certain) |
Every close approach NASA has on record for this object — 70 total.
It orbits the Sun. Not Earth, and not Venus. The column above does not say what the asteroid goes around — it says which planet a given close approach was to. 63 of them were approaches to Earth, 6 of them were approaches to Mars and 1 of them were approaches to Moon.
This one’s path runs from 0.990 AU at its closest to the Sun out to 1.505 AU at its farthest. For scale, Venus orbits at about 0.72 AU and Earth at 1.00 AU — so an orbit spanning that range crosses the path of every planet in between, once on the way out and once on the way back.
Crossing a planet’s path is not the same as meeting the planet. Almost every time the asteroid crosses, that planet is somewhere else along its own orbit. A close approach is logged only on the rare occasions when both happen to arrive at the crossing point at roughly the same time — which is why the dates below are scattered rather than regular. This object takes 508.9 days to go round, against Earth’s 365.25, so the two drift in and out of step over years rather than repeating on a neat cycle.
The Minimum Orbit Intersection Distance in the table above (0.0098 AU) is the closest the two paths ever come. The miss distances below are how far apart the two bodies actually were on the day, which is almost always very much larger.
next approach: 2027-07-09
| Date | Passed near | Velocity (km/h) | Miss distance |
|---|---|---|---|
| 2076-10-27 | Earth | 43987.13 | 45,766,549 km 119 LD |
| 2073-07-03 | Earth | 27139.10 | 71,717,077 km 187 LD |
| 2069-11-21 | Earth | 14183.12 | 6,274,108 km 16.3 LD |
| 2066-06-21 | Earth | 27878.67 | 73,893,700 km 192 LD |
| 2062-12-17 | Earth | 9821.98 | 1,492,740 km 3.88 LD |
| 2062-12-17 | Moon | 6017.15 | 1,284,494 km 3.34 LD |
| 2059-06-13 | Earth | 27796.84 | 73,514,280 km 191 LD |
| 2056-01-21 | Earth | 19783.62 | 13,255,483 km 34.5 LD |
| 2052-06-01 | Earth | 27271.25 | 71,866,629 km 187 LD |
| 2049-02-04 | Earth | 41563.49 | 42,415,007 km 110 LD |
| 2048-09-07 | Earth | 14805.50 | 44,383,784 km 115 LD |
| 2045-05-17 | Earth | 25901.49 | 68,055,816 km 177 LD |
| 2042-02-15 | Earth | 64058.39 | 73,640,325 km 192 LD |
| 2041-08-14 | Earth | 20839.74 | 56,892,263 km 148 LD |
| 2038-04-30 | Earth | 23201.74 | 61,286,274 km 159 LD |
| 2037-05-23 | Mars | 14279.59 | 5,612,298 km 14.6 LD |
| 2034-07-25 | Earth | 24477.52 | 65,339,808 km 170 LD |
| 2031-04-08 | Earth | 18382.75 | 50,683,211 km 132 LD |
| 2030-10-22 | Earth | 51648.16 | 56,373,180 km 147 LD |
| 2027-07-09 next | Earth | 26618.58 | 70,563,636 km 184 LD |
| 2024-03-05 | Earth | 8996.11 | 34,545,372 km 89.9 LD |
| 2023-11-04 | Earth | 28704.91 | 24,752,827 km 64.4 LD |
| 2020-06-24 | Earth | 27596.69 | 73,010,444 km 190 LD |
| 2016-12-06 | Earth | 10122.05 | 1,606,819 km 4.18 LD |
| 2013-06-21 | Earth | 28012.81 | 74,776,848 km 195 LD |
| 2010-02-17 | Earth | 4162.63 | 30,602,013 km 79.6 LD |
| 2009-11-06 | Earth | 24551.23 | 19,138,927 km 49.8 LD |
| 2006-07-03 | Earth | 27506.84 | 73,509,405 km 191 LD |
| 2003-03-29 | Earth | 16609.90 | 47,525,647 km 124 LD |
| 2002-10-24 | Earth | 45639.22 | 47,911,409 km 125 LD |
| 1999-07-18 | Earth | 25966.04 | 69,590,565 km 181 LD |
| 1996-04-19 | Earth | 22133.97 | 59,272,043 km 154 LD |
| 1992-08-03 | Earth | 23161.05 | 62,746,261 km 163 LD |
| 1989-05-07 | Earth | 25422.33 | 67,334,335 km 175 LD |
| 1986-02-08 | Earth | 54001.74 | 59,536,492 km 155 LD |
| 1985-08-24 | Earth | 18502.51 | 52,445,576 km 136 LD |
| 1982-05-23 | Earth | 27300.04 | 72,332,085 km 188 LD |
| 1979-01-27 | Earth | 31928.77 | 29,249,110 km 76.1 LD |
| 1978-09-23 | Earth | 10115.02 | 37,480,843 km 97.5 LD |
| 1975-06-06 | Earth | 28079.04 | 74,591,169 km 194 LD |
| 1972-01-06 | Earth | 12395.05 | 4,524,166 km 11.8 LD |
| 1968-06-06 | Earth | 27685.27 | 73,299,755 km 191 LD |
| 1965-12-09 | Mars | 15636.30 | 3,700,349 km 9.63 LD |
| 1965-01-21 | Earth | 24419.08 | 19,381,866 km 50.4 LD |
| 1961-05-28 | Earth | 27183.77 | 71,812,333 km 187 LD |
| 1959-12-30 | Mars | 18334.51 | 5,572,407 km 14.5 LD |
| 1958-02-01 | Earth | 41856.05 | 42,778,599 km 111 LD |
| 1957-09-04 | Earth | 14782.57 | 44,624,879 km 116 LD |
| 1954-05-15 | Earth | 26004.99 | 68,517,324 km 178 LD |
| 1951-02-11 | Earth | 61592.68 | 70,097,890 km 182 LD |
| 1950-08-14 | Earth | 20384.16 | 55,767,597 km 145 LD |
| 1947-04-30 | Earth | 23823.69 | 62,907,850 km 164 LD |
| 1943-07-27 | Earth | 23836.91 | 63,737,862 km 166 LD |
| 1940-04-12 | Earth | 20309.60 | 54,607,311 km 142 LD |
| 1939-10-16 | Earth | 58867.23 | 66,602,767 km 173 LD |
| 1936-07-12 | Earth | 25988.71 | 69,075,304 km 180 LD |
| 1933-03-21 | Earth | 14515.28 | 43,096,817 km 112 LD |
| 1932-10-25 | Earth | 39505.27 | 39,538,049 km 103 LD |
| 1929-06-29 | Earth | 27200.34 | 72,146,827 km 188 LD |
| 1925-11-07 | Earth | 21565.64 | 15,256,722 km 39.7 LD |
| 1922-06-20 | Earth | 27759.13 | 73,546,352 km 191 LD |
| 1918-11-24 | Earth | 11548.57 | 2,969,057 km 7.72 LD |
| 1916-09-21 | Mars | 18204.37 | 3,354,482 km 8.73 LD |
| 1912-03-23 | Earth | 16076.82 | 46,671,111 km 121 LD |
| 1911-10-22 | Earth | 43957.17 | 45,456,828 km 118 LD |
| 1911-01-27 | Mars | 19723.62 | 6,695,878 km 17.4 LD |
| 1908-07-16 | Earth | 25804.01 | 69,470,583 km 181 LD |
| 1905-06-04 | Mars | 21397.49 | 10,479,408 km 27.3 LD |
| 1905-04-24 | Earth | 23499.47 | 62,738,979 km 163 LD |
| 1901-08-10 | Earth | 21292.27 | 58,540,148 km 152 LD |
Looked up from NASA's NeoWs API and cached — last refreshed 2026-09-05T00:44:55.983389+00:00.