SpaceAtlas Space Object Data
NASA JPL SBDB · 259221

259221

259221 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.1 AU it takes 1.15 yr to circle the Sun.

Apollo Observations: 389
Orbital Period · P
1.15 yr
v(q)
94.3 km/s
v(Q)
8.6 km/s
Diameter · ≈
0.51 km
TJ
5.2
Eccentricity · e
0.8333

Orbit and dynamics

Between its closest point (0.183 AU) and its farthest (2.017 AU), the heliocentric distance changes by 1.834 AU over every revolution.

One full revolution takes 1.15 yr (421 days), computed from the semi-major axis of 1.1 AU.

The high eccentricity (0.833) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

A steep inclination of 23.71° carries it well above and below the ecliptic plane.

By the vis-viva equation its orbital speed rises to 94.3 km/s at perihelion and falls to 8.6 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 = 19.2 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.51 km.

Observation record and orbit quality

Astrometry from 389 individual observations underpins this orbit; the fit leaves an RMS residual of 0.4235 arcseconds.

Condition code U = 0 means the orbit is very well determined, leaving only a small uncertainty in the future ephemeris.

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
1.1 AU
Eccentricity
0.8333
Perihelion
0.183 AU
Aphelion
2.01663 AU
Inclination
23.71°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
171.3°

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
2041-Jan-08 08:35 0.186798 AU
27944574 km
26.52 km/s
2056-Jan-09 10:12 0.179576 AU
26864209 km
26.75 km/s
2071-Jan-09 09:46 0.175233 AU
26214437 km
26.91 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
19.2

Orbit Quality

RMS
0.42353
Condition
0
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

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