SpaceAtlas Space Object Data
NASA JPL SBDB · 2018 RA

2018 RA

2018 RA belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.883 AU it takes 2.58 yr to circle the Sun.

Apollo Observations: 68
Orbital Period · P
2.58 yr
v(q)
35.9 km/s
v(Q)
13.1 km/s
Diameter · ≈
0.02 km
TJ
3.83
Eccentricity · e
0.4636

Orbit and dynamics

The path is an ellipse reaching 1.01 AU from the Sun at perihelion and 2.756 AU at aphelion, a radial span of 1.746 AU.

Applying Kepler's third law to a = 1.883 AU gives an orbital period of 2.58 yr, or about 944 days.

The high eccentricity (0.464) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

Its inclination of 4.43° keeps it close to the plane of the ecliptic.

By the vis-viva equation its orbital speed rises to 35.9 km/s at perihelion and falls to 13.1 km/s at aphelion.

Size and surface

No direct size measurement is available; from an absolute magnitude of H = 26.7 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.02 km.

Observation record and orbit quality

The current orbit solution is based on 68 observations and has a weighted RMS residual of 0.3805 arcseconds.

Condition code U = 7 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
1.883 AU
Eccentricity
0.4636
Perihelion
1.01 AU
Aphelion
2.755959 AU
Inclination
4.43°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
358.91°

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
2031-Jul-11 14:33 0.320841 AU
47997084 km
20.44 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
26.7

Orbit Quality

RMS
0.38049
Condition
7
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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