SpaceAtlas Space Object Data
NASA JPL SBDB · 2018 RJ3

2018 RJ3

2018 RJ3 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.329 AU it takes 1.53 yr to circle the Sun.

Apollo Observations: 48
Orbital Period · P
1.53 yr
v(q)
35.5 km/s
v(Q)
18.8 km/s
Diameter · ≈
0.01 km
TJ
4.87
Eccentricity · e
0.3066

Orbit and dynamics

Between its closest point (0.921 AU) and its farthest (1.736 AU), the heliocentric distance changes by 0.815 AU over every revolution.

One full revolution takes 1.53 yr (560 days), computed from the semi-major axis of 1.329 AU.

An eccentricity of 0.307 makes the orbit moderately elongated.

The orbital plane is tilted 6.09° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 35.5 km/s at perihelion and falls to 18.8 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 = 27.8 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.01 km.

Observation record and orbit quality

Astrometry from 48 individual observations underpins this orbit; the fit leaves an RMS residual of 0.4225 arcseconds.

Condition code U = 6 indicates a moderately constrained orbit; predictions decades ahead still carry noticeable uncertainty.

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
1.329 AU
Eccentricity
0.3066
Perihelion
0.921 AU
Aphelion
1.736471 AU
Inclination
6.09°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
48.68°

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
2038-May-08 04:12 0.129622 AU
19391136 km
12.41 km/s
2038-Nov-06 03:05 0.445862 AU
66700079 km
7.09 km/s
2044-Sep-25 16:30 0.144059 AU
21550960 km
14.90 km/s
2061-Apr-28 08:10 0.283417 AU
42398573 km
17.80 km/s
2067-Apr-02 23:20 0.377373 AU
56454221 km
6.62 km/s
2067-Sep-15 05:18 0.003164 AU
473373 km
9.91 km/s
2070-Oct-08 13:40 0.438109 AU
65540145 km
21.96 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
27.8

Orbit Quality

RMS
0.42254
Condition
6
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.