SpaceAtlas Space Object Data
NASA JPL SBDB · 2022 UN21

2022 UN21

2022 UN21 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.78 AU it takes 2.37 yr to circle the Sun.

Apollo Observations: 37
Orbital Period · P
2.37 yr
v(q)
38.7 km/s
v(Q)
12.9 km/s
Diameter · ≈
0.02 km
TJ
3.93
Eccentricity · e
0.5004

Orbit and dynamics

Between its closest point (0.889 AU) and its farthest (2.671 AU), the heliocentric distance changes by 1.782 AU over every revolution.

One full revolution takes 2.37 yr (867 days), computed from the semi-major axis of 1.78 AU.

The high eccentricity (0.5) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

The orbital plane is tilted 7.57° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 38.7 km/s at perihelion and falls to 12.9 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 = 26.5 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.02 km.

Observation record and orbit quality

Astrometry from 37 individual observations underpins this orbit; the fit leaves an RMS residual of 0.5121 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
1.78 AU
Eccentricity
0.5004
Perihelion
0.889 AU
Aphelion
2.670712 AU
Inclination
7.57°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
168.6°

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
26.5

Orbit Quality

RMS
0.51209
Condition
7
Orbit ID
—
Data source: NASA JPL Small-Body Database . 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

Explore asteroids, comets and near-Earth objects with JPL orbital data.