SpaceAtlas Space Object Data
NASA JPL SBDB · 2025 SB21

2025 SB21

2025 SB21 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.846 AU it takes 2.51 yr to circle the Sun.

Apollo Observations: 9
Orbital Period · P
2.51 yr
v(q)
36.2 km/s
v(Q)
13.3 km/s
TJ
3.87
Eccentricity · e
0.463

Orbit and dynamics

Between its closest point (0.992 AU) and its farthest (2.701 AU), the heliocentric distance changes by 1.709 AU over every revolution.

One full revolution takes 2.51 yr (916 days), computed from the semi-major axis of 1.846 AU.

The high eccentricity (0.463) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

The orbital plane is tilted 6.9° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 36.2 km/s at perihelion and falls to 13.3 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

Neither a measured diameter nor a reliable absolute magnitude is available for 2025 SB21, so its physical size remains unconstrained.

Observation record and orbit quality

Astrometry from 9 individual observations underpins this orbit; the fit leaves an RMS residual of 0.2214 arcseconds.

Condition code U = 9 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
1.846 AU
Eccentricity
0.463
Perihelion
0.992 AU
Aphelion
2.700698 AU
Inclination
6.9°
Orbital Period
— yr
Epoch
2460946.5
Mean Anomaly
4.99°

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
31.32

Orbit Quality

RMS
0.22142
Condition
9
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.

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