SpaceAtlas Space Object Data
NASA JPL SBDB · 2021 JD

2021 JD

2021 JD is an Amor-type near-Earth asteroid that approaches Earth from beyond our orbit without crossing it, orbiting the Sun at 1.306 AU once every 1.49 yr.

Amor Observations: 31
Orbital Period · P
1.49 yr
v(q)
31.7 km/s
v(Q)
21.4 km/s
Diameter · ≈
0.02 km
TJ
4.97
Eccentricity · e
0.1943

Orbit and dynamics

The path is an ellipse reaching 1.052 AU from the Sun at perihelion and 1.56 AU at aphelion, a radial span of 0.508 AU.

Applying Kepler's third law to a = 1.306 AU gives an orbital period of 1.49 yr, or about 545 days.

An eccentricity of 0.194 makes the orbit moderately elongated.

Its inclination of 3.19° keeps it close to the plane of the ecliptic.

By the vis-viva equation its orbital speed rises to 31.7 km/s at perihelion and falls to 21.4 km/s at aphelion.

Its perihelion lies just outside Earth's orbit, which is why it is classed as Earth-approaching rather than Earth-crossing.

Size and surface

No direct size measurement is available; from an absolute magnitude of H = 26.61 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 31 observations and has a weighted RMS residual of 0.5968 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
1.306 AU
Eccentricity
0.1943
Perihelion
1.052 AU
Aphelion
1.559756 AU
Inclination
3.19°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
142.82°

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
2027-Apr-23 13:37 0.092995 AU
13911802 km
6.50 km/s
2030-Apr-16 01:33 0.182608 AU
27317741 km
9.72 km/s
2033-Apr-09 19:16 0.286077 AU
42796477 km
13.14 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
26.61

Orbit Quality

RMS
0.59677
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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