SpaceAtlas Space Object Data
NASA JPL SBDB · 503966

503966

503966 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 2.211 AU it takes 3.29 yr to circle the Sun.

Apollo Observations: 128
Orbital Period · P
3.29 yr
v(q)
62.1 km/s
v(Q)
6.5 km/s
Diameter · ≈
0.76 km
TJ
3.02
Eccentricity · e
0.8113

Orbit and dynamics

Between its closest point (0.417 AU) and its farthest (4.005 AU), the heliocentric distance changes by 3.588 AU over every revolution.

One full revolution takes 3.29 yr (1,201 days), computed from the semi-major axis of 2.211 AU.

The high eccentricity (0.811) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

A steep inclination of 28.99° carries it well above and below the ecliptic plane.

By the vis-viva equation its orbital speed rises to 62.1 km/s at perihelion and falls to 6.5 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 = 18.34 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.76 km.

Observation record and orbit quality

Astrometry from 128 individual observations underpins this orbit; the fit leaves an RMS residual of 0.5875 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
2.211 AU
Eccentricity
0.8113
Perihelion
0.417 AU
Aphelion
4.004784 AU
Inclination
28.99°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
245.73°

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
2040-Sep-27 02:14 0.369934 AU
55341375 km
37.13 km/s
2047-Feb-01 06:26 0.458823 AU
68638957 km
35.07 km/s
2063-Sep-22 11:39 0.292535 AU
43762582 km
33.56 km/s
2070-Jan-27 22:43 0.483335 AU
72305946 km
36.75 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
18.34

Orbit Quality

RMS
0.5875
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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