SpaceAtlas Space Object Data
NASA JPL SBDB · 518635

518635

518635 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 2.914 AU it takes 4.97 yr to circle the Sun.

Apollo Observations: 1,391
Orbital Period · P
4.97 yr
v(q)
38 km/s
v(Q)
8 km/s
Diameter · ≈
0.83 km
TJ
2.89
Eccentricity · e
0.6515

Orbit and dynamics

The path is an ellipse reaching 1.016 AU from the Sun at perihelion and 4.812 AU at aphelion, a radial span of 3.796 AU.

Applying Kepler's third law to a = 2.914 AU gives an orbital period of 4.97 yr, or about 1,817 days.

The high eccentricity (0.651) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

The orbital plane is tilted 14.09° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 38 km/s at perihelion and falls to 8 km/s at aphelion.

Size and surface

No direct size measurement is available; from an absolute magnitude of H = 18.17 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.83 km.

Observation record and orbit quality

The current orbit solution is based on 1,391 observations and has a weighted RMS residual of 0.4014 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
2.914 AU
Eccentricity
0.6515
Perihelion
1.016 AU
Aphelion
4.812471 AU
Inclination
14.09°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
199.32°

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
2028-Sep-14 14:50 0.168654 AU
25230255 km
10.52 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
18.17

Orbit Quality

RMS
0.4014
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.

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