Illustration of Earth with several asteroids passing at different distances, one flagged as potentially hazardous

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482234 (2011 CG71)

Designation: 482234 · NASA id: 2482234

Estimated diameter: 83 – 186 meters

≈ a football pitch
That comparison is of size only — what an impact would do depends on speed, angle, composition and where it arrives, none of which follows from width.
(absolute magnitude H = 22.52) · JPL Small-Body Database →

Earth impact concern
No identified impact threat
Why?
  • Its closest recorded pass was 20.2 lunar distances.
  • It is not on NASA/JPL’s Sentry list, which holds every object with a computed chance of impact above zero. Most objects are not on it.
What the four levels mean
  • No identified impact threat — not on any risk list. 98.8% of the objects here.
  • On a monitored risk list — a computed chance above zero, however small. 1.2% of the objects here.
  • Among the highest-ranked — Palermo at or above −2. Two objects worldwide qualify, both studied for decades and both centuries away.
  • Exceptional — Torino 1 or more, or Palermo at or above zero. No object anywhere currently qualifies.

These describe where an object sits in a catalogue, not how dangerous it is. The full ranked list is on the impact risk page.

Energy of motion, if it ever entered the atmosphere

1.3 megatonnes – 47.4 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.

Why is one asteroid “hazardous” when closer ones are not?

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:

  • Its orbit can bring it within 0.05 AU of Earth’s — about 7.5 million km. This is the Minimum Orbit Intersection Distance, the closest the two paths ever come, not the distance on any given pass.
  • It is big enough to matter — absolute magnitude 22.0 or brighter, which is roughly 140 metres across and up. That threshold is a planning convention, not a physical boundary: it is about the size at which an impact could do regional damage. Smaller objects are not harmless, they are simply outside this definition — the Chelyabinsk object of 2013 was around 20 metres and injured about 1,500 people with the shock wave from its airburst, without ever reaching the ground intact.

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.

Orbital Data

Orbit class: AMO — Near-Earth asteroid orbits similar to that of 1221 Amor
1.017 AU < q (perihelion) < 1.3 AU

Orbital period554.5 days (1.52 years)
Eccentricity.1626375247861426 (0 = circular, closer to 1 = more elongated)
Semi-major axis1.320863667614421 AU
Inclination4.531188200612689° (tilt of its orbit vs. Earth's)
Perihelion distance1.106041670133665 AU (closest approach to the Sun)
Aphelion distance1.535685665095176 AU (farthest from the Sun)
Minimum Orbit Intersection Distance0.11766 AU = 17,601,686 km
(closest its orbit path ever comes to Earth's, regardless of timing)
Ascending node longitude329.2674359878492°
Argument of perihelion178.8980626886071°
Mean anomaly / motion28.49300010296252° / .6492576601649065°/day
Jupiter Tisserand invariant4.931 (helps distinguish asteroids from comets)
Reference epoch / equinoxJD 2461200.5 / J2000
Orbit determined2021-04-14 17:03:09
Observed2011-01-28 to 2019-10-19 (3186 day arc, 67 observations used)
Orbit uncertainty1 (0 = best known, 9 = least certain)

Close Approach History

Every close approach NASA has on record for this object — 82 total.

Why does it pass Earth and Mars? Doesn’t it orbit just one?

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. 77 of them were approaches to Earth and 5 of them were approaches to Mars.

This one’s path runs from 1.106 AU at its closest to the Sun out to 1.536 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 554.5 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 (0.1177 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: 2037-07-24

Date Passed near Velocity (km/h) Miss distance
2195-10-07 Earth 24985.88 71,259,215 km
185 LD
2195-04-08 Mars 22954.75 9,188,210 km
23.9 LD
2192-10-24 Earth 21901.39 64,645,532 km
168 LD
2189-11-15 Earth 17310.16 55,433,352 km
144 LD
2186-12-14 Earth 10629.49 42,809,540 km
111 LD
2184-01-29 Earth 8114.74 25,575,543 km
66.5 LD
2181-03-04 Earth 8715.45 19,290,396 km
50.2 LD
2178-04-20 Earth 6751.51 36,526,382 km
95.0 LD
2175-05-27 Earth 14058.48 51,026,822 km
133 LD
2172-06-19 Earth 19677.57 61,454,544 km
160 LD
2169-07-09 Earth 23328.21 69,074,533 km
180 LD
2166-07-26 Earth 25845.83 74,266,011 km
193 LD
2154-09-25 Earth 26327.46 74,538,741 km
194 LD
2151-10-12 Earth 24223.84 69,474,778 km
181 LD
2148-10-30 Earth 20640.14 62,025,142 km
161 LD
2148-04-17 Mars 17257.56 13,010,352 km
33.8 LD
2145-11-22 Earth 15350.01 51,768,800 km
135 LD
2142-12-27 Earth 8239.62 37,516,800 km
97.6 LD
2140-02-11 Earth 8708.29 19,962,738 km
51.9 LD
2137-03-17 Earth 8028.91 24,658,679 km
64.1 LD
2134-05-05 Earth 9111.61 42,206,293 km
110 LD
2131-06-05 Earth 16235.25 55,057,139 km
143 LD
2128-06-26 Earth 21171.78 64,477,301 km
168 LD
2125-07-15 Earth 24307.96 71,183,616 km
185 LD
2110-09-30 Earth 25673.82 72,967,204 km
190 LD
2107-10-18 Earth 23140.51 67,046,537 km
174 LD
2104-11-06 Earth 19019.06 58,747,868 km
153 LD
2101-12-02 Earth 12901.78 47,301,729 km
123 LD
2099-01-11 Earth 7252.26 31,511,550 km
82.0 LD
2096-02-21 Earth 8757.24 17,602,752 km
45.8 LD
2093-04-02 Earth 6614.48 30,857,837 km
80.3 LD
2090-05-15 Earth 11698.57 46,941,367 km
122 LD
2087-06-11 Earth 18030.88 58,479,253 km
152 LD
2084-07-01 Earth 22335.31 66,895,794 km
174 LD
2081-07-18 Earth 25082.44 72,866,894 km
190 LD
2066-10-04 Earth 25017.12 71,410,363 km
186 LD
2063-10-22 Earth 22126.28 64,842,522 km
169 LD
2061-09-25 Mars 19593.48 7,759,271 km
20.2 LD
2060-11-11 Earth 17435.62 55,667,584 km
145 LD
2057-12-11 Earth 10643.53 43,116,000 km
112 LD
2055-01-26 Earth 8018.21 25,785,561 km
67.1 LD
2052-03-01 Earth 8714.31 19,162,462 km
49.9 LD
2049-04-17 Earth 6766.24 36,430,535 km
94.8 LD
2046-05-24 Earth 13977.16 51,006,178 km
133 LD
2043-06-18 Earth 19591.80 61,570,534 km
160 LD
2040-07-06 Earth 23416.03 69,198,384 km
180 LD
2037-07-24 next Earth 25787.87 74,414,223 km
194 LD
2025-09-23 Earth 26358.19 74,357,599 km
193 LD
2022-10-10 Earth 24030.05 69,155,419 km
180 LD
2019-10-29 Earth 20525.02 61,512,664 km
160 LD
2016-11-21 Earth 14999.69 51,054,360 km
133 LD
2013-12-27 Earth 7832.98 36,564,006 km
95.1 LD
2011-02-11 Earth 8728.94 19,311,611 km
50.2 LD
2008-03-17 Earth 7875.13 25,749,782 km
67.0 LD
2005-05-04 Earth 9688.07 43,080,879 km
112 LD
2002-06-03 Earth 16583.51 55,743,704 km
145 LD
1999-06-25 Earth 21267.18 64,956,616 km
169 LD
1996-07-13 Earth 24512.39 71,553,709 km
186 LD
1981-09-28 Earth 25661.22 72,638,298 km
189 LD
1978-10-16 Earth 22896.12 66,623,716 km
173 LD
1975-11-06 Earth 18801.50 58,081,992 km
151 LD
1975-03-16 Mars 21996.29 8,491,657 km
22.1 LD
1972-12-01 Earth 12495.97 46,426,773 km
121 LD
1970-01-12 Earth 7200.68 30,381,743 km
79.0 LD
1967-02-21 Earth 8762.91 17,588,497 km
45.8 LD
1964-04-03 Earth 6600.84 31,774,098 km
82.7 LD
1961-05-15 Earth 12161.65 47,605,833 km
124 LD
1958-06-10 Earth 18269.57 58,970,263 km
153 LD
1955-07-01 Earth 22392.51 67,290,962 km
175 LD
1952-07-17 Earth 25220.46 73,106,721 km
190 LD
1937-10-03 Earth 25025.46 71,116,935 km
185 LD
1934-10-21 Earth 21880.46 64,414,192 km
168 LD
1931-11-12 Earth 17276.81 55,124,112 km
143 LD
1928-12-10 Earth 10332.08 42,398,729 km
110 LD
1928-03-26 Mars 17145.12 13,762,832 km
35.8 LD
1926-01-26 Earth 8116.95 24,949,021 km
64.9 LD
1923-03-02 Earth 8696.04 19,747,114 km
51.4 LD
1920-04-18 Earth 7216.25 37,277,602 km
97.0 LD
1917-05-23 Earth 14342.51 51,607,674 km
134 LD
1914-06-17 Earth 19817.85 62,029,623 km
161 LD
1911-07-06 Earth 23443.65 69,512,023 km
181 LD
1908-07-23 Earth 25902.40 74,623,747 km
194 LD

Looked up from NASA's NeoWs API and cached — last refreshed 2026-09-04T23:01:40.632616+00:00.