SpaceAtlas Space Object Data
NASA JPL SBDB · 2021 FF

2021 FF

2021 FF belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.537 AU it takes 1.91 yr to circle the Sun.

Apollo Observations: 49
Orbital Period · P
1.91 yr
v(q)
34.8 km/s
v(Q)
16.6 km/s
Diameter · ≈
0.02 km
TJ
4.4
Eccentricity · e
0.355

Orbit and dynamics

The path is an ellipse reaching 0.991 AU from the Sun at perihelion and 2.083 AU at aphelion, a radial span of 1.092 AU.

Applying Kepler's third law to a = 1.537 AU gives an orbital period of 1.91 yr, or about 696 days.

An eccentricity of 0.355 makes the orbit moderately elongated.

Its inclination of 2.58° keeps it close to the plane of the ecliptic.

By the vis-viva equation its orbital speed rises to 34.8 km/s at perihelion and falls to 16.6 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 = 26.34 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 49 observations and has a weighted RMS residual of 0.6097 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
1.537 AU
Eccentricity
0.355
Perihelion
0.991 AU
Aphelion
2.082635 AU
Inclination
2.58°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
281.02°

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-Dec-22 21:11 0.250729 AU
37508585 km
18.56 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
26.34

Orbit Quality

RMS
0.60967
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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