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Designation: 509505 · NASA id: 2509505
Estimated diameter: 150 – 336 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.
37.6 megatonnes – 1,401 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 | 330.8 days (0.91 years) |
| Eccentricity | .3594315840355399 (0 = circular, closer to 1 = more elongated) |
| Semi-major axis | .9360528523444558 AU |
| Inclination | 9.340429116176116° (tilt of its orbit vs. Earth's) |
| Perihelion distance | .5996058928853027 AU (closest approach to the Sun) |
| Aphelion distance | 1.272499811803609 AU (farthest from the Sun) |
| Minimum Orbit Intersection Distance | 0.11018 AU = 16,482,544 km (closest its orbit path ever comes to Earth's, regardless of timing) |
| Ascending node longitude | 62.30543880627364° |
| Argument of perihelion | 194.7464517279992° |
| Mean anomaly / motion | 310.1098795665044° / 1.088312249500601°/day |
| Jupiter Tisserand invariant | 6.340 (helps distinguish asteroids from comets) |
| Reference epoch / equinox | JD 2461200.5 / J2000 |
| Orbit determined | 2026-10-13 06:57:58 |
| Observed | 2007-11-05 to 2026-10-12 (6916 day arc, 100 observations used) |
| Orbit uncertainty | 0 (0 = best known, 9 = least certain) |
Every close approach NASA has on record for this object — 88 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. 53 of them were approaches to Venus and 35 of them were approaches to Earth.
This one’s path runs from 0.600 AU at its closest to the Sun out to 1.272 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 330.8 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 (0.1102 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 |
|---|---|---|---|
| 2198-10-19 | Earth | 56976.69 | 27,646,940 km 71.9 LD |
| 2189-10-29 | Earth | 32391.89 | 27,393,470 km 71.3 LD |
| 2187-08-30 | Venus | 39357.79 | 8,151,232 km 21.2 LD |
| 2185-12-10 | Venus | 37710.46 | 19,532,233 km 50.8 LD |
| 2184-03-16 | Venus | 52079.07 | 14,964,617 km 38.9 LD |
| 2182-02-08 | Earth | 39550.25 | 23,531,826 km 61.2 LD |
| 2179-10-18 | Earth | 47111.17 | 18,389,885 km 47.8 LD |
| 2172-04-05 | Venus | 53041.69 | 12,479,896 km 32.5 LD |
| 2170-07-09 | Venus | 38052.22 | 18,557,159 km 48.3 LD |
| 2168-10-22 | Venus | 37727.76 | 12,040,534 km 31.3 LD |
| 2163-02-06 | Earth | 48524.57 | 26,244,801 km 68.3 LD |
| 2160-10-17 | Earth | 39151.28 | 16,476,285 km 42.9 LD |
| 2155-01-31 | Venus | 34839.25 | 12,554,750 km 32.7 LD |
| 2153-05-15 | Venus | 34668.14 | 18,115,682 km 47.1 LD |
| 2151-08-12 | Venus | 62942.86 | 22,046,034 km 57.4 LD |
| 2141-10-22 | Earth | 33508.05 | 21,737,117 km 56.5 LD |
| 2139-09-02 | Venus | 43390.73 | 7,862,874 km 20.5 LD |
| 2137-12-10 | Venus | 38393.80 | 19,539,300 km 50.8 LD |
| 2136-03-20 | Venus | 46466.71 | 12,506,395 km 32.5 LD |
| 2134-02-06 | Earth | 33092.37 | 25,468,053 km 66.3 LD |
| 2131-10-19 | Earth | 53749.09 | 24,286,265 km 63.2 LD |
| 2124-04-08 | Venus | 60189.46 | 17,806,167 km 46.3 LD |
| 2122-11-02 | Earth | 32579.00 | 29,607,778 km 77.0 LD |
| 2122-07-06 | Venus | 36708.22 | 16,890,104 km 43.9 LD |
| 2120-10-21 | Venus | 32675.99 | 14,399,843 km 37.5 LD |
| 2115-02-07 | Earth | 42338.08 | 23,675,000 km 61.6 LD |
| 2112-10-16 | Earth | 44232.16 | 16,970,705 km 44.1 LD |
| 2107-01-28 | Venus | 37392.83 | 9,174,130 km 23.9 LD |
| 2105-05-12 | Venus | 37035.99 | 19,255,005 km 50.1 LD |
| 2103-08-15 | Venus | 55878.20 | 17,163,890 km 44.7 LD |
| 2096-02-04 | Earth | 51142.86 | 27,905,924 km 72.6 LD |
| 2093-10-16 | Earth | 37506.61 | 17,314,214 km 45.0 LD |
| 2091-09-04 | Venus | 48111.08 | 9,563,664 km 24.9 LD |
| 2089-12-09 | Venus | 38476.90 | 19,180,768 km 49.9 LD |
| 2088-03-22 | Venus | 41594.17 | 11,620,744 km 30.2 LD |
| 2076-04-11 | Venus | 65830.10 | 22,315,397 km 58.1 LD |
| 2074-10-24 | Earth | 32738.49 | 24,310,168 km 63.2 LD |
| 2074-07-04 | Venus | 35387.65 | 14,976,358 km 39.0 LD |
| 2072-10-17 | Venus | 32835.93 | 16,559,114 km 43.1 LD |
| 2067-02-06 | Earth | 35486.41 | 24,214,748 km 63.0 LD |
| 2064-10-16 | Earth | 51110.55 | 21,815,407 km 56.8 LD |
| 2059-01-29 | Venus | 40926.15 | 7,943,848 km 20.7 LD |
| 2057-05-11 | Venus | 38057.42 | 19,522,134 km 50.8 LD |
| 2055-08-18 | Venus | 50495.45 | 14,095,886 km 36.7 LD |
| 2048-02-06 | Earth | 44255.51 | 24,051,517 km 62.6 LD |
| 2045-10-15 | Earth | 42917.86 | 16,685,933 km 43.4 LD |
| 2043-09-06 | Venus | 54639.77 | 13,709,678 km 35.7 LD |
| 2041-12-08 | Venus | 37820.07 | 18,207,882 km 47.4 LD |
| 2040-03-24 | Venus | 36037.63 | 12,444,342 km 32.4 LD |
| 2026-10-18 next | Earth | 35202.68 | 19,404,413 km 50.5 LD |
| 2026-07-02 | Venus | 34865.53 | 12,252,204 km 31.9 LD |
| 2024-10-15 | Venus | 35105.38 | 18,238,791 km 47.4 LD |
| 2023-01-12 | Venus | 61649.44 | 21,077,333 km 54.8 LD |
| 2019-02-01 | Earth | 30638.05 | 28,056,446 km 73.0 LD |
| 2016-10-18 | Earth | 58394.30 | 29,500,682 km 76.7 LD |
| 2011-02-02 | Venus | 44661.56 | 8,297,390 km 21.6 LD |
| 2009-05-11 | Venus | 38490.46 | 19,438,996 km 50.6 LD |
| 2007-10-27 | Earth | 32347.94 | 26,838,038 km 69.8 LD |
| 2007-08-21 | Venus | 45529.74 | 12,168,034 km 31.7 LD |
| 2000-02-06 | Earth | 37712.50 | 23,461,191 km 61.0 LD |
| 1997-10-15 | Earth | 48696.87 | 19,959,835 km 51.9 LD |
| 1995-09-09 | Venus | 62157.62 | 19,423,330 km 50.5 LD |
| 1993-12-05 | Venus | 36227.13 | 16,273,307 km 42.3 LD |
| 1992-03-21 | Venus | 32390.90 | 15,126,036 km 39.3 LD |
| 1981-02-04 | Earth | 47725.94 | 25,522,225 km 66.4 LD |
| 1978-10-15 | Earth | 39480.86 | 16,801,048 km 43.7 LD |
| 1978-06-30 | Venus | 37919.26 | 8,969,437 km 23.3 LD |
| 1976-10-11 | Venus | 37376.43 | 19,290,783 km 50.2 LD |
| 1975-01-15 | Venus | 54310.08 | 16,156,459 km 42.0 LD |
| 1963-02-04 | Venus | 49852.62 | 10,663,641 km 27.7 LD |
| 1961-05-11 | Venus | 38410.64 | 18,967,861 km 49.3 LD |
| 1959-10-20 | Earth | 33816.54 | 21,341,216 km 55.5 LD |
| 1959-08-24 | Venus | 40252.15 | 11,566,747 km 30.1 LD |
| 1952-02-03 | Earth | 31975.01 | 26,200,557 km 68.2 LD |
| 1949-10-17 | Earth | 55318.72 | 26,258,650 km 68.3 LD |
| 1945-12-03 | Venus | 34899.53 | 13,851,501 km 36.0 LD |
| 1944-03-17 | Venus | 33817.46 | 17,284,812 km 45.0 LD |
| 1940-10-30 | Earth | 32505.41 | 29,304,627 km 76.2 LD |
| 1933-02-05 | Earth | 40462.48 | 23,176,898 km 60.3 LD |
| 1930-10-15 | Earth | 45807.76 | 18,167,123 km 47.3 LD |
| 1930-07-02 | Venus | 42255.58 | 8,036,267 km 20.9 LD |
| 1928-10-11 | Venus | 38324.81 | 19,483,804 km 50.7 LD |
| 1927-01-18 | Venus | 48452.18 | 13,121,543 km 34.1 LD |
| 1915-02-07 | Venus | 56399.23 | 15,092,075 km 39.3 LD |
| 1914-02-03 | Earth | 49557.88 | 26,550,394 km 69.1 LD |
| 1913-05-09 | Venus | 37518.83 | 17,824,106 km 46.4 LD |
| 1911-10-16 | Earth | 37812.08 | 17,543,673 km 45.6 LD |
| 1911-08-25 | Venus | 34625.33 | 12,982,773 km 33.8 LD |
Looked up from NASA's NeoWs API and cached — last refreshed 2026-10-15T09:15:26.796029+00:00.