Where is it now
- Distance from Sun
- 1.167 AU
- True anomaly
- 176.69°
- Distance from Earth
- 0.341 AU
- As of
- 11 October 2026
Two-body Kepler propagation — accurate to ~0.1% for major planets over decades, less so for highly-perturbed bodies. Use JPL Horizons for high precision.
In the sky
- Right ascension
- 21h 18m 40s
- Declination
- -35° 00′ 06″
- Constellation
- Microscopium
- Distance from Earth
- 0.35 AU
- Elongation from the Sun
- 110.92° — well clear of the Sun
Favours the southern hemisphere; low or below the horizon from far north.
From your location
See how high it is right now, whether it is up after civil twilight, and when it rises and sets where you are.
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Two-body approximation, good to about a degree for the planets — enough to find the constellation and know whether it is up.
Orbital elements
- Semi-major axis
- 0.788 AU
- Eccentricity
- 0.4837
- Inclination
- 5.42°
- Orbital period
- 255.3 days
- Perihelion
- 0.407 AU
- Aphelion
- 1.169 AU
- Longitude of ascending node
- 101.88°
- Argument of periapsis
- 84.99°
- Epoch · J2000
- 2461200.5
- Orbit class · ATE
- Aten
- Earth MOID · 28.7 LD
- 0.0737 AU
- Tisserand (Jupiter)
- 7.285
Orbit quality
Orbit very well determined (uncertainty code 0).
- Observations used
- 2,468
- Data arc
- 43.84 years
- First observed
- 4 December 1982
- Last observed
- 8 October 2026
- Residual RMS
- 0.37 ″
- Solution · Otto Matic
- 9 October 2026
Physical properties
- Mean radius
- 1.43 km
- Rotation period
- 2.38 hours
Visual & observation
- Geometric albedo
- 0.224
- Absolute magnitude (H)
- 14.36
Discovery & classification
- Discovered by
- LINEAR
- Discovery date
- 13 October 1998
- Discovery site
- Socorro
Also known as 1998 TU3
Close approaches 248 on record
Top-down view of the ecliptic, Earth at the centre, for the 2031-11-07 13:21 UTC close approach of 66146. Catalogue miss distance 32.3 LD · 1.24 × 10⁷ km. The curve is the geocentric path from 2031-11-04 to 2031-11-10, with a mark at UTC midnights and an arrow for the direction of motion. The circle is the Moon’s mean orbit; the Moon is plotted at closest approach. A ray shows the Sun’s direction. The labelled distance is the full separation. The drawn radius is the part that lies in the ecliptic plane. At closest approach the object is south of the ecliptic. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate.
| When (UTC) | Body | Distance | Lunar distances | Relative speed |
|---|---|---|---|---|
| 2031-11-07 13:21:00 | Earth | 0.0829 AU | 32.3 LD | 13.5 km/s |
| 2033-06-17 20:59:00 | Mercury | 0.0394 AU | 15.3 LD | 15.9 km/s |
| 2033-06-17 20:59:00 | Merc | 0.0394 AU | 15.3 LD | 15.9 km/s |
| 2033-09-01 07:03:00 | Earth | 0.132 AU | 51.4 LD | 10.1 km/s |
| 2036-02-14 19:03:00 | Venus | 0.0376 AU | 14.6 LD | 16.4 km/s |
| 2037-09-22 17:01:00 | Venus | 0.0152 AU | 5.9 LD | 18.2 km/s |
| 2038-11-06 14:20:00 | Earth | 0.1184 AU | 46.1 LD | 15.5 km/s |
| 2040-06-17 06:11:00 | Merc | 0.0678 AU | 26.4 LD | 20.9 km/s |
| 2040-06-17 06:11:00 | Mercury | 0.0678 AU | 26.4 LD | 20.9 km/s |
| 2040-09-07 21:30:00 | Earth | 0.1604 AU | 62.4 LD | 9.9 km/s |
Next ten from today. 1 lunar distance = 384,400 km. Source: JPL close-approach data.
Sources
- visual properties: JPL SBDB (lookup)
- physical properties: JPL SBDB (lookup)
- physical properties: JPL SBDB (lookup)
- visual properties: JPL SBDB (lookup)
- orbital elements: JPL SBDB