SpaceAtlasSpace Object Data

2018 AP18

2018 AP18 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 2.073 AU it takes 2.98 yr to circle the Sun.

Apollo Observations: 44

Orbit and dynamics

Between its closest point (0.482 AU) and its farthest (3.664 AU), the heliocentric distance changes by 3.182 AU over every revolution.

One full revolution takes 2.98 yr (1,090 days), computed from the semi-major axis of 2.073 AU.

The high eccentricity (0.768) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

The orbital plane is tilted 9.81° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 57 km/s at perihelion and falls to 7.5 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 = 17.74 and an assumed geometric albedo of 0.14, the diameter works out to roughly 1.01 km.

Observation record and orbit quality

Astrometry from 44 individual observations underpins this orbit; the fit leaves an RMS residual of 0.5319 arcseconds.

Condition code U = 2 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
2.073 AU
Eccentricity
0.7677
Perihelion
0.482 AU
Aphelion
3.664442 AU
Inclination
9.81°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
30.99°

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

No close approaches to Earth are currently on record for this object.

Physical Parameters

Diameter
— km
Albedo
—
Density
— g/cm³
Rotation Period
— h
Absolute Magnitude
17.74

Orbit Quality

RMS
0.53193
Condition
2
Orbit ID
—