SpaceAtlas Space Object Data
NASA JPL SBDB · 308899

308899

308899 is an Amor-type near-Earth asteroid that approaches Earth from beyond our orbit without crossing it, orbiting the Sun at 1.8 AU once every 2.41 yr.

Amor Observations: 350
Orbital Period · P
2.41 yr
v(q)
32.9 km/s
v(Q)
15 km/s
Diameter · ≈
0.77 km
TJ
3.94
Eccentricity · e
0.3736

Orbit and dynamics

The path is an ellipse reaching 1.127 AU from the Sun at perihelion and 2.472 AU at aphelion, a radial span of 1.345 AU.

Applying Kepler's third law to a = 1.8 AU gives an orbital period of 2.41 yr, or about 882 days.

An eccentricity of 0.374 makes the orbit moderately elongated.

The orbital plane is tilted 16.55° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 32.9 km/s at perihelion and falls to 15 km/s at aphelion.

Its perihelion lies just outside Earth's orbit, which is why it is classed as Earth-approaching rather than Earth-crossing.

Size and surface

No direct size measurement is available; from an absolute magnitude of H = 18.31 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.77 km.

Observation record and orbit quality

The current orbit solution is based on 350 observations and has a weighted RMS residual of 0.6128 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
1.8 AU
Eccentricity
0.3736
Perihelion
1.127 AU
Aphelion
2.47248 AU
Inclination
16.55°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
39.69°

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

No close approaches to Earth are currently on record for this object.

Physical Parameters

Diameter
— km
Albedo
—
Density
— g/cm³
Rotation Period
— h
Absolute Magnitude
18.31

Orbit Quality

RMS
0.61279
Condition
0
Orbit ID
—
Data source: NASA JPL Small-Body Database . 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.