SpaceAtlas Space Object Data
NASA JPL SBDB · 2016 RH18

2016 RH18

2016 RH18 is an Amor-type near-Earth asteroid that approaches Earth from beyond our orbit without crossing it, orbiting the Sun at 1.546 AU once every 1.92 yr.

Amor Observations: 119
Orbital Period · P
1.92 yr
v(q)
31.3 km/s
v(Q)
18.3 km/s
Diameter · ≈
0.17 km
TJ
4.41
Eccentricity · e
0.2626

Orbit and dynamics

The path is an ellipse reaching 1.14 AU from the Sun at perihelion and 1.952 AU at aphelion, a radial span of 0.812 AU.

Applying Kepler's third law to a = 1.546 AU gives an orbital period of 1.92 yr, or about 702 days.

An eccentricity of 0.263 makes the orbit moderately elongated.

The orbital plane is tilted 8.94° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 31.3 km/s at perihelion and falls to 18.3 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 = 21.62 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.17 km.

Observation record and orbit quality

The current orbit solution is based on 119 observations and has a weighted RMS residual of 0.391 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
1.546 AU
Eccentricity
0.2626
Perihelion
1.14 AU
Aphelion
1.95198 AU
Inclination
8.94°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
332.14°

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
2041-Oct-29 04:41 0.328197 AU
49097601 km
4.36 km/s
2043-Dec-11 06:42 0.225466 AU
33729223 km
5.12 km/s
2066-Nov-12 17:16 0.265613 AU
39735145 km
5.20 km/s
2068-Dec-21 04:09 0.287538 AU
43015048 km
4.85 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
21.62

Orbit Quality

RMS
0.39099
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.