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Designation: 2016 JG38 · NASA id: 3753578
Estimated diameter: 42 – 93 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.
824 kilotonnes – 30.7 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: 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 | 738.0 days (2.02 years) |
| Eccentricity | .4558780144452437 (0 = circular, closer to 1 = more elongated) |
| Semi-major axis | 1.598215307574326 AU |
| Inclination | 3.721988399517605° (tilt of its orbit vs. Earth's) |
| Perihelion distance | .8696240865013478 AU (closest approach to the Sun) |
| Aphelion distance | 2.326806528647304 AU (farthest from the Sun) |
| Minimum Orbit Intersection Distance | 0.01890 AU = 2,827,864 km (closest its orbit path ever comes to Earth's, regardless of timing) |
| Ascending node longitude | 29.53888385513469° |
| Argument of perihelion | 288.39957338405° |
| Mean anomaly / motion | 219.8144984087382° / .4878105008494807°/day |
| Jupiter Tisserand invariant | 4.240 (helps distinguish asteroids from comets) |
| Reference epoch / equinox | JD 2461000.5 / J2000 |
| Orbit determined | 2024-11-02 06:55:21 |
| Observed | 2016-05-01 to 2024-10-30 (3104 day arc, 53 observations used) |
| Orbit uncertainty | 0 (0 = best known, 9 = least certain) |
Every close approach NASA has on record for this object — 48 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. 39 of them were approaches to Earth, 8 of them were approaches to Mars and 1 of them were approaches to Venus.
This one’s path runs from 0.870 AU at its closest to the Sun out to 2.327 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 738.0 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 (0.0189 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: 2026-10-18
| Date | Passed near | Velocity (km/h) | Miss distance |
|---|---|---|---|
| 2133-11-02 | Earth | 83949.47 | 61,270,713 km 159 LD |
| 2131-10-28 | Earth | 71955.16 | 44,613,989 km 116 LD |
| 2129-10-22 | Earth | 60475.61 | 28,502,541 km 74.1 LD |
| 2127-10-16 | Earth | 49127.34 | 12,720,058 km 33.1 LD |
| 2125-10-07 | Earth | 39542.94 | 2,710,088 km 7.05 LD |
| 2123-09-21 | Earth | 31824.37 | 14,505,959 km 37.7 LD |
| 2121-08-23 | Earth | 32806.93 | 22,352,535 km 58.1 LD |
| 2119-07-28 | Earth | 32472.63 | 22,486,279 km 58.5 LD |
| 2117-06-30 | Earth | 31481.43 | 16,105,347 km 41.9 LD |
| 2115-06-13 | Earth | 39366.73 | 7,839,643 km 20.4 LD |
| 2113-06-04 | Earth | 50252.99 | 16,459,327 km 42.8 LD |
| 2111-05-28 | Earth | 61998.29 | 32,018,627 km 83.3 LD |
| 2109-05-21 | Earth | 74632.73 | 49,566,462 km 129 LD |
| 2107-05-16 | Earth | 87047.43 | 67,221,075 km 175 LD |
| 2103-10-12 | Mars | 32789.95 | 7,149,445 km 18.6 LD |
| 2097-01-10 | Mars | 34335.02 | 3,064,286 km 7.97 LD |
| 2049-03-26 | Mars | 34186.10 | 7,441,788 km 19.4 LD |
| 2042-06-26 | Mars | 34231.90 | 2,766,170 km 7.20 LD |
| 2030-11-01 | Earth | 85860.04 | 64,127,677 km 167 LD |
| 2028-10-25 | Earth | 71568.16 | 44,105,590 km 115 LD |
| 2026-10-18 next | Earth | 56963.47 | 23,576,778 km 61.3 LD |
| 2024-10-08 | Earth | 43101.75 | 5,061,700 km 13.2 LD |
| 2022-09-26 | Earth | 33525.14 | 10,517,762 km 27.4 LD |
| 2020-08-29 | Earth | 32145.80 | 20,853,186 km 54.2 LD |
| 2018-08-02 | Earth | 32856.61 | 23,074,602 km 60.0 LD |
| 2016-07-04 | Earth | 31114.35 | 18,006,875 km 46.8 LD |
| 2014-06-13 | Earth | 37972.40 | 8,105,215 km 21.1 LD |
| 2012-06-02 | Earth | 49076.41 | 15,008,711 km 39.0 LD |
| 2010-05-27 | Earth | 61049.28 | 30,745,776 km 80.0 LD |
| 2008-05-19 | Earth | 73619.40 | 48,269,518 km 126 LD |
| 2006-05-14 | Earth | 86144.76 | 65,994,095 km 172 LD |
| 1994-09-10 | Mars | 35872.45 | 9,887,990 km 25.7 LD |
| 1987-12-11 | Mars | 31548.85 | 5,076,939 km 13.2 LD |
| 1947-12-10 | Venus | 15069.11 | 21,553,213 km 56.1 LD |
| 1923-11-01 | Earth | 85859.10 | 64,244,968 km 167 LD |
| 1921-10-25 | Earth | 73615.59 | 47,072,781 km 122 LD |
| 1919-10-20 | Earth | 60997.13 | 29,313,020 km 76.3 LD |
| 1917-10-12 | Earth | 49479.61 | 13,550,944 km 35.3 LD |
| 1915-10-04 | Earth | 39381.94 | 3,310,763 km 8.61 LD |
| 1913-09-16 | Earth | 31704.69 | 15,006,669 km 39.0 LD |
| 1911-12-07 | Mars | 35088.40 | 8,314,484 km 21.6 LD |
| 1911-08-20 | Earth | 32592.52 | 22,307,306 km 58.0 LD |
| 1909-07-24 | Earth | 32438.91 | 22,513,283 km 58.6 LD |
| 1907-06-26 | Earth | 31847.11 | 15,203,702 km 39.6 LD |
| 1905-06-09 | Earth | 40207.50 | 7,317,273 km 19.0 LD |
| 1905-03-09 | Mars | 30835.19 | 6,991,251 km 18.2 LD |
| 1903-05-31 | Earth | 51420.79 | 17,710,568 km 46.1 LD |
| 1901-05-24 | Earth | 63805.29 | 34,484,252 km 89.7 LD |
Looked up from NASA's NeoWs API and cached — last refreshed 2026-10-15T22:00:37.384340+00:00.