SpaceAtlas Space Object Data
NASA JPL SBDB · 666729

666729

666729 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.699 AU it takes 2.21 yr to circle the Sun.

Apollo Observations: 629
Orbital Period · P
2.21 yr
v(q)
40.6 km/s
v(Q)
12.9 km/s
Diameter · ≈
0.64 km
TJ
4.03
Eccentricity · e
0.519

Orbit and dynamics

The path is an ellipse reaching 0.817 AU from the Sun at perihelion and 2.581 AU at aphelion, a radial span of 1.764 AU.

Applying Kepler's third law to a = 1.699 AU gives an orbital period of 2.21 yr, or about 809 days.

The high eccentricity (0.519) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

The orbital plane is tilted 9.79° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 40.6 km/s at perihelion and falls to 12.9 km/s at aphelion.

Because q < 1 AU and Q > 1 AU, this orbit geometrically intersects the region of Earth's orbit.

Size and surface

No direct size measurement is available; from an absolute magnitude of H = 18.72 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.64 km.

Observation record and orbit quality

The current orbit solution is based on 629 observations and has a weighted RMS residual of 0.3631 arcseconds.

Condition code U = 0 means the orbit is very well determined, leaving only a small uncertainty in the future ephemeris.

About these computed values

Orbital periods, perihelion and aphelion speeds, and diameter estimates on this page are computed by SpaceAtlas from the JPL SBDB orbital elements. They are derived quantities, not values copied from the source catalogue.

Orbital Parameters

Semi-Major Axis
1.699 AU
Eccentricity
0.519
Perihelion
0.817 AU
Aphelion
2.580781 AU
Inclination
9.79°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
343.21°

Orbit diagram

The Sun sits at the focus (orange). Earth's orbit is the grey circle at 1 AU. The red dot marks the object's position at the catalog epoch.

3D orbit (interactive)

Drag to rotate; scroll or pinch to zoom. The Sun is at the focus (orange), Earth's orbit is the grey ring at 1 AU, and the red dot marks the object's current position.

Close approaches

Predicted close approaches to Earth, from NASA's Center for Near-Earth Object Studies (CNEOS).

Date (UTC)Miss distanceVelocity
2030-Nov-07 18:57 0.274354 AU
41042720 km
20.80 km/s
2033-Apr-23 08:04 0.488638 AU
73099185 km
26.15 km/s
2041-Dec-24 12:27 0.145978 AU
21838068 km
10.96 km/s
2053-Mar-28 19:03 0.166944 AU
24974406 km
13.35 km/s
2061-Nov-10 10:37 0.229324 AU
34306326 km
19.52 km/s
2073-Jan-05 01:02 0.174329 AU
26079299 km
11.13 km/s

Distances in astronomical units (AU) and kilometres. Source: NASA/JPL CNEOS Close Approach Data API.

Physical Parameters

Diameter
— km
Albedo
—
Density
— g/cm³
Rotation Period
— h
Absolute Magnitude
18.72

Orbit Quality

RMS
0.36307
Condition
0
Orbit ID
—
Data source: NASA JPL Small-Body Database · NASA CNEOS. Orbital periods, perihelion and aphelion speeds, and diameter estimates on this page are computed by SpaceAtlas from the JPL SBDB orbital elements. They are derived quantities, not values copied from the source catalogue.

Keep exploring

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