SpaceAtlas Space Object Data
NASA JPL SBDB · 2018 AM12

2018 AM12

2018 AM12 is an Aten-type near-Earth asteroid whose orbit lies mostly inside that of Earth, with a semi-major axis of 0.917 AU and a period of 0.88 yr.

Aten Observations: 128
Orbital Period · P
0.88 yr
v(q)
34.9 km/s
v(Q)
27.7 km/s
Diameter · ≈
0.21 km
TJ
6.45
Eccentricity · e
0.1162

Orbit and dynamics

The path is an ellipse reaching 0.811 AU from the Sun at perihelion and 1.024 AU at aphelion, a radial span of 0.213 AU.

Applying Kepler's third law to a = 0.917 AU gives an orbital period of 0.88 yr, or about 321 days.

An eccentricity of 0.116 makes the orbit moderately elongated.

A steep inclination of 21.67° carries it well above and below the ecliptic plane.

By the vis-viva equation its orbital speed rises to 34.9 km/s at perihelion and falls to 27.7 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 = 21.16 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.21 km.

Observation record and orbit quality

The current orbit solution is based on 128 observations and has a weighted RMS residual of 0.398 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
0.9172 AU
Eccentricity
0.1162
Perihelion
0.811 AU
Aphelion
1.023779 AU
Inclination
21.67°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
322.2°

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
2040-Jan-08 14:10 0.187928 AU
28113649 km
11.63 km/s
2047-Jan-09 12:16 0.032450 AU
4854407 km
11.36 km/s
2047-Jun-26 13:30 0.183493 AU
27450189 km
13.00 km/s
2054-Jan-11 05:35 0.072933 AU
10910619 km
12.32 km/s
2054-Jul-08 00:00 0.171453 AU
25648992 km
12.67 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
21.16

Orbit Quality

RMS
0.398
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.

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