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Designation: 2019 FF · NASA id: 3840124
Estimated diameter: 15 – 33 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.
36 kilotonnes – 1.3 megatonnes 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: ATE — Near-Earth asteroid orbits similar to that of 2062 Aten
a (semi-major axis) < 1.0 AU; q (perihelion) > 0.983 AU
| Orbital period | 293.2 days (0.80 years) |
| Eccentricity | .2645621071816733 (0 = circular, closer to 1 = more elongated) |
| Semi-major axis | .8638232842954351 AU |
| Inclination | 9.086861748252559° (tilt of its orbit vs. Earth's) |
| Perihelion distance | .6352883759696412 AU (closest approach to the Sun) |
| Aphelion distance | 1.092358192621229 AU (farthest from the Sun) |
| Minimum Orbit Intersection Distance | 0.00345 AU = 516,745 km (closest its orbit path ever comes to Earth's, regardless of timing) |
| Ascending node longitude | .9256249099083383° |
| Argument of perihelion | 318.9642340724993° |
| Mean anomaly / motion | 356.7072895969224° / 1.227627799793354°/day |
| Jupiter Tisserand invariant | 6.800 (helps distinguish asteroids from comets) |
| Reference epoch / equinox | JD 2461000.5 / J2000 |
| Orbit determined | 2021-04-15 21:06:15 |
| Observed | 2019-03-18 to 2019-03-20 (2 day arc, 23 observations used) |
| Orbit uncertainty | 7 (0 = best known, 9 = least certain) |
Every close approach NASA has on record for this object — 55 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. 47 of them were approaches to Earth, 7 of them were approaches to Venus and 1 of them were approaches to Moon.
This one’s path runs from 0.635 AU at its closest to the Sun out to 1.092 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 293.2 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 (0.0035 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: 2026-10-23
| Date | Passed near | Velocity (km/h) | Miss distance |
|---|---|---|---|
| 2074-03-02 | Venus | 42143.49 | 13,919,461 km 36.2 LD |
| 2072-03-22 | Earth | 29554.17 | 1,602,897 km 4.17 LD |
| 2071-10-02 | Earth | 39374.34 | 47,997,188 km 125 LD |
| 2068-03-23 | Earth | 35316.46 | 7,798,873 km 20.3 LD |
| 2064-03-22 | Earth | 44872.13 | 21,551,002 km 56.1 LD |
| 2060-03-19 | Earth | 55472.15 | 36,072,490 km 93.8 LD |
| 2056-03-15 | Earth | 66876.49 | 51,267,692 km 133 LD |
| 2055-01-04 | Earth | 75708.67 | 68,193,482 km 177 LD |
| 2052-03-11 | Earth | 78890.68 | 67,152,643 km 175 LD |
| 2050-12-31 | Earth | 63231.76 | 53,391,253 km 139 LD |
| 2047-07-19 | Earth | 44397.26 | 57,838,989 km 150 LD |
| 2046-12-26 | Earth | 50863.10 | 39,445,053 km 103 LD |
| 2043-07-05 | Earth | 39997.89 | 56,100,405 km 146 LD |
| 2042-12-23 | Earth | 38579.78 | 28,132,530 km 73.2 LD |
| 2039-06-20 | Earth | 34255.39 | 53,075,681 km 138 LD |
| 2038-12-22 | Earth | 27308.15 | 23,290,302 km 60.6 LD |
| 2035-06-03 | Earth | 26311.93 | 48,176,041 km 125 LD |
| 2034-10-24 | Venus | 53059.96 | 21,915,947 km 57.0 LD |
| 2031-02-11 | Earth | 23981.33 | 23,327,697 km 60.7 LD |
| 2030-11-10 | Earth | 23512.02 | 35,149,195 km 91.4 LD |
| 2027-03-04 | Earth | 24089.72 | 17,849,462 km 46.4 LD |
| 2026-10-23 next | Earth | 31144.56 | 41,016,225 km 107 LD |
| 2026-09-24 | Venus | 32673.59 | 12,471,779 km 32.4 LD |
| 2023-03-19 | Earth | 26053.69 | 8,345,540 km 21.7 LD |
| 2022-10-09 | Earth | 36720.12 | 45,668,591 km 119 LD |
| 2019-03-23 | Earth | 31110.75 | 1,208,739 km 3.14 LD |
| 2019-03-23 | Moon | 31323.08 | 1,093,549 km 2.84 LD |
| 2018-09-26 | Earth | 40421.81 | 48,607,352 km 126 LD |
| 2018-08-04 | Venus | 31544.80 | 16,681,008 km 43.4 LD |
| 2016-04-20 | Venus | 32837.34 | 9,774,561 km 25.4 LD |
| 2015-03-20 | Earth | 53018.09 | 32,758,575 km 85.2 LD |
| 2014-08-29 | Earth | 46633.12 | 55,268,264 km 144 LD |
| 2011-03-13 | Earth | 76856.44 | 64,626,955 km 168 LD |
| 2010-08-02 | Earth | 46498.43 | 57,812,305 km 150 LD |
| 2009-12-29 | Earth | 62306.03 | 52,440,620 km 136 LD |
| 2006-07-04 | Earth | 39530.77 | 55,661,136 km 145 LD |
| 2005-12-21 | Earth | 37305.28 | 27,393,665 km 71.3 LD |
| 1994-03-23 | Earth | 40937.15 | 16,038,954 km 41.7 LD |
| 1990-03-17 | Earth | 63777.15 | 47,261,946 km 123 LD |
| 1989-01-03 | Earth | 76329.55 | 69,203,113 km 180 LD |
| 1984-12-25 | Earth | 53027.65 | 41,916,204 km 109 LD |
| 1980-12-19 | Earth | 29544.51 | 23,782,604 km 61.9 LD |
| 1973-03-20 | Earth | 27238.70 | 5,689,277 km 14.8 LD |
| 1972-10-04 | Earth | 37953.65 | 46,497,037 km 121 LD |
| 1969-05-20 | Venus | 30188.66 | 16,531,504 km 43.0 LD |
| 1969-03-22 | Earth | 43040.42 | 18,957,655 km 49.3 LD |
| 1968-09-10 | Earth | 44816.99 | 52,949,360 km 138 LD |
| 1967-02-07 | Venus | 34957.52 | 9,894,002 km 25.7 LD |
| 1965-03-17 | Earth | 62793.80 | 45,993,838 km 120 LD |
| 1964-08-18 | Earth | 47498.30 | 56,897,314 km 148 LD |
| 1964-01-05 | Earth | 78003.10 | 71,257,366 km 185 LD |
| 1961-03-10 | Earth | 82618.83 | 72,011,870 km 187 LD |
| 1959-12-28 | Earth | 57583.33 | 47,003,512 km 122 LD |
| 1955-12-21 | Earth | 36607.37 | 26,893,893 km 70.0 LD |
| 1944-03-23 | Earth | 32261.57 | 2,938,875 km 7.65 LD |
Looked up from NASA's NeoWs API and cached — last refreshed 2026-10-17T22:20:40.557321+00:00.