SpaceAtlas Space Object Data
NASA JPL SBDB · 2018 XR4

2018 XR4

2018 XR4 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.144 AU it takes 1.22 yr to circle the Sun.

Apollo Observations: 27
Orbital Period · P
1.22 yr
v(q)
40.5 km/s
v(Q)
19.2 km/s
Diameter · ≈
0.02 km
TJ
5.41
Eccentricity · e
0.3574

Orbit and dynamics

Between its closest point (0.735 AU) and its farthest (1.553 AU), the heliocentric distance changes by 0.818 AU over every revolution.

One full revolution takes 1.22 yr (447 days), computed from the semi-major axis of 1.144 AU.

An eccentricity of 0.357 makes the orbit moderately elongated.

The orbital plane is tilted 10.21° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 40.5 km/s at perihelion and falls to 19.2 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 = 26.8 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.02 km.

Observation record and orbit quality

Astrometry from 27 individual observations underpins this orbit; the fit leaves an RMS residual of 0.4644 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
1.144 AU
Eccentricity
0.3574
Perihelion
0.735 AU
Aphelion
1.552866 AU
Inclination
10.21°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
350.75°

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
2034-Nov-26 00:45 0.268395 AU
40151297 km
25.10 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
26.8

Orbit Quality

RMS
0.46445
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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