SpaceAtlas Space Object Data
NASA JPL SBDB · 2021 OS1

2021 OS1

2021 OS1 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.871 AU it takes 2.56 yr to circle the Sun.

Apollo Observations: 47
Orbital Period · P
2.56 yr
v(q)
35.7 km/s
v(Q)
13.3 km/s
Diameter · ≈
0.04 km
TJ
3.84
Eccentricity · e
0.4566

Orbit and dynamics

Between its closest point (1.016 AU) and its farthest (2.725 AU), the heliocentric distance changes by 1.709 AU over every revolution.

One full revolution takes 2.56 yr (935 days), computed from the semi-major axis of 1.871 AU.

The high eccentricity (0.457) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

The orbital plane is tilted 5.14° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 35.7 km/s at perihelion and falls to 13.3 km/s at aphelion.

Size and surface

No direct size measurement is available; from an absolute magnitude of H = 24.77 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.04 km.

Observation record and orbit quality

Astrometry from 47 individual observations underpins this orbit; the fit leaves an RMS residual of 0.5166 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
1.871 AU
Eccentricity
0.4566
Perihelion
1.016 AU
Aphelion
2.725299 AU
Inclination
5.14°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
309.91°

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
2062-Jul-24 04:39 0.115460 AU
17272579 km
13.38 km/s
2067-Nov-02 18:20 0.336659 AU
50363447 km
19.21 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
24.77

Orbit Quality

RMS
0.51659
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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