SpaceAtlas Space Object Data
NASA JPL SBDB · 2016 US31

2016 US31

2016 US31 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.521 AU it takes 1.88 yr to circle the Sun.

Apollo Observations: 25
Orbital Period · P
1.88 yr
v(q)
35.4 km/s
v(Q)
16.5 km/s
Diameter · ≈
0.03 km
TJ
4.43
Eccentricity · e
0.365

Orbit and dynamics

The path is an ellipse reaching 0.966 AU from the Sun at perihelion and 2.076 AU at aphelion, a radial span of 1.11 AU.

Applying Kepler's third law to a = 1.521 AU gives an orbital period of 1.88 yr, or about 685 days.

An eccentricity of 0.365 makes the orbit moderately elongated.

Its inclination of 1.64° keeps it close to the plane of the ecliptic.

By the vis-viva equation its orbital speed rises to 35.4 km/s at perihelion and falls to 16.5 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 = 25.2 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.03 km.

Observation record and orbit quality

The current orbit solution is based on 25 observations and has a weighted RMS residual of 0.363 arcseconds.

Condition code U = 8 signals a poorly constrained orbit, so its future path should be treated as provisional.

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
1.521 AU
Eccentricity
0.365
Perihelion
0.966 AU
Aphelion
2.076165 AU
Inclination
1.64°
Orbital Period
— yr
Epoch
2457687.5
Mean Anomaly
18.99°

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
2048-Jul-07 00:19 0.174988 AU
26177864 km
16.46 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
25.2

Orbit Quality

RMS
0.36303
Condition
8
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.