SpaceAtlas Space Object Data
NASA JPL SBDB · 2018 JA1

2018 JA1

2018 JA1 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.325 AU it takes 1.53 yr to circle the Sun.

Apollo Observations: 110
Orbital Period · P
1.53 yr
v(q)
33.3 km/s
v(Q)
20.1 km/s
Diameter · ≈
0.02 km
TJ
4.9
Eccentricity · e
0.2489

Orbit and dynamics

The path is an ellipse reaching 0.996 AU from the Sun at perihelion and 1.655 AU at aphelion, a radial span of 0.659 AU.

Applying Kepler's third law to a = 1.325 AU gives an orbital period of 1.53 yr, or about 557 days.

An eccentricity of 0.249 makes the orbit moderately elongated.

The orbital plane is tilted 6.37° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 33.3 km/s at perihelion and falls to 20.1 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 = 25.82 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 110 observations and has a weighted RMS residual of 0.4462 arcseconds.

Condition code U = 6 indicates a moderately constrained orbit; predictions decades ahead still carry noticeable uncertainty.

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
1.325 AU
Eccentricity
0.2489
Perihelion
0.996 AU
Aphelion
1.654792 AU
Inclination
6.37°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
88.61°

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
2044-Apr-13 07:18 0.278361 AU
41642185 km
15.52 km/s
2044-Oct-01 14:59 0.401931 AU
60127975 km
6.61 km/s
2050-Jul-22 09:18 0.127786 AU
19116516 km
7.16 km/s
2053-Aug-14 03:13 0.266719 AU
39900549 km
15.19 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
25.82

Orbit Quality

RMS
0.44622
Condition
6
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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