SpaceAtlas Space Object Data
NASA JPL SBDB · 2018 NR4

2018 NR4

2018 NR4 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 2.133 AU it takes 3.12 yr to circle the Sun.

Apollo Observations: 46
Orbital Period · P
3.12 yr
v(q)
36.6 km/s
v(Q)
11.3 km/s
Diameter · ≈
0.33 km
TJ
2.96
Eccentricity · e
0.5272

Orbit and dynamics

Between its closest point (1.009 AU) and its farthest (3.258 AU), the heliocentric distance changes by 2.249 AU over every revolution.

One full revolution takes 3.12 yr (1,138 days), computed from the semi-major axis of 2.133 AU.

The high eccentricity (0.527) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

A steep inclination of 61.58° carries it well above and below the ecliptic plane.

By the vis-viva equation its orbital speed rises to 36.6 km/s at perihelion and falls to 11.3 km/s at aphelion.

Size and surface

No direct size measurement is available; from an absolute magnitude of H = 20.16 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.33 km.

Observation record and orbit quality

Astrometry from 46 individual observations underpins this orbit; the fit leaves an RMS residual of 0.6171 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
2.133 AU
Eccentricity
0.5272
Perihelion
1.009 AU
Aphelion
3.257518 AU
Inclination
61.58°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
161.2°

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
2047-Jan-17 17:23 0.450602 AU
67409094 km
33.02 km/s
2071-Jul-28 08:09 0.470013 AU
70312912 km
32.54 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
20.16

Orbit Quality

RMS
0.61713
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.