2011 CQ1 is a meteoroid discovered on 4 February 2011 by Richard A. Kowalski, at the Catalina Sky Survey.[1] On the same day the meteoroid passed within 0.85 Earth radii (5,480 kilometers (3,410 mi)) of Earth's surface, and was perturbed from the Apollo class to the Aten class of near-Earth objects.[5] With a relative velocity of only 9.7 km/s,[2] had the asteroid passed less than 0.5 Earth radii from Earth's surface, it would have fallen as a brilliant fireball. The meteoroid is between 80 centimeters (31 in) and 2.6 meters (100 in) wide.[5] The meteoroid was removed from the Sentry Risk Table on 5 February 2011.[6]
| Discovery[1] | |
|---|---|
| Discovered by | Catalina Sky Survey Richard A. Kowalski |
| Discovery date | 4 February 2011 |
| Designations | |
| 2011 CQ1 | |
|
| |
| Orbital characteristics[2] | |
| Epoch 13 January 2016 (JD 2457400.5) | |
| Uncertainty parameter5 | |
| Observation arc | 12.4 hours[3] (35 observations used) |
| Aphelion | 1.0087 AU (150.90 Gm) (Q) |
| Perihelion | 0.66454 AU (99.414 Gm) (q) |
| 0.83661 AU (125.155 Gm) (a) | |
| Eccentricity | 0.20567 (e) |
| 0.77 yr (279.5 d) | |
| 18.607° (M) | |
| 1.2880°/day (n) | |
| Inclination | 5.2445° (i) |
| 315.23° (Ω) | |
| 335.40° (ω) | |
| Earth MOID | 0.000166307 AU (24,879.2 km) |
| Jupiter MOID | 4.09715 AU (612.925 Gm) |
| Physical characteristics | |
| Dimensions | ~2 meters (79 in) |
| 14.2 (2011 peak)[4] | |
| 32.1[2] | |
| Parameter | Epoch | aphelion (Q) |
perihelion (q) |
Semi-major axis (a) |
eccentricity (e) |
Period (p) |
inclination (i) |
Longitude ascending node (Ω) |
Mean anomaly (M) |
Argument of perihelion (ω) |
|---|---|---|---|---|---|---|---|---|---|---|
| Units | AU | (days) | (°) | |||||||
| Pre-flyby | 2011-Jan-26 | 1.347 | 0.9096 | 1.128 | 0.1940 | 437.9 | 1.073° | 135.4° | 310.9° | 58.59° |
| Post-flyby | 2011-Feb-08 | 1.009 | 0.6624 | 0.8360 | 0.2076 | 279.2 | 5.296° | 315.4° | 220.6° | 335.1° |
It was not until 2020 QG on 16 August 2020 that a non-impacting closer approach to Earth was observed.
| Asteroid | Date | Distance from surface of Earth |
Uncertainty in approach distance |
Observation arc | Reference |
|---|---|---|---|---|---|
| 2020 VT4 | 2020-11-13 17:21 | 368 km | ±11 km | 5 days (34 obs) | data |
| 2020 QG | 2020-08-16 04:09 | 2939 km | ±11 km | 2 days (35 obs) | data |
| 2021 UA1 | 2021-10-25 03:07 | 3049 km | ±10 km | 1 day (22 obs) | data |
| 2023 BU | 2023-01-27 00:29 | 3589 km | ±<1 km | 10 days (231 obs) | data |
| 2011 CQ1 | 2011-02-04 19:39 | 5474 km | ±5 km | 1 day (35 obs) | data |
| 2019 UN13 | 2019-10-31 14:45 | 6235 km | ±189 km | 1 day (16 obs) | data |
| 2008 TS26 | 2008-10-09 03:30 | 6260 km | ±970 km | 1 day (19 obs) | data |
| 2004 FU162 | 2004-03-31 15:35 | 6535 km | ±13000 km | 1 day (4 obs) | data |
