SpaceAtlas Space Object Data
NASA JPL SBDB · 285331

285331

285331 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.736 AU it takes 2.29 yr to circle the Sun.

Apollo Observations: 539
Orbital Period · P
2.29 yr
v(q)
37 km/s
v(Q)
13.8 km/s
Diameter · ≈
0.82 km
TJ
3.96
Eccentricity · e
0.4557

Orbit and dynamics

The path is an ellipse reaching 0.945 AU from the Sun at perihelion and 2.527 AU at aphelion, a radial span of 1.582 AU.

Applying Kepler's third law to a = 1.736 AU gives an orbital period of 2.29 yr, or about 835 days.

The high eccentricity (0.456) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

A steep inclination of 20.16° carries it well above and below the ecliptic plane.

By the vis-viva equation its orbital speed rises to 37 km/s at perihelion and falls to 13.8 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

The measured diameter is 0.65 km, a value from direct size determination rather than from brightness alone.

A geometric albedo of 0.198 points to a comparatively bright, reflective surface.

Observation record and orbit quality

The current orbit solution is based on 539 observations and has a weighted RMS residual of 0.4649 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
1.736 AU
Eccentricity
0.4557
Perihelion
0.945 AU
Aphelion
2.527095 AU
Inclination
20.16°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
299.41°

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
2031-May-18 03:45 0.084789 AU
12684230 km
13.69 km/s
2047-May-27 12:49 0.135595 AU
20284770 km
13.78 km/s

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

Physical Parameters

Diameter
0.654 km
Albedo
0.198
Density
— g/cm³
Rotation Period
— h
Absolute Magnitude
18.19

Orbit Quality

RMS
0.46489
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

Explore asteroids, comets and near-Earth objects with JPL orbital data.