SpaceAtlas Space Object Data
NASA JPL SBDB · 399774

399774

399774 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 2.045 AU it takes 2.92 yr to circle the Sun.

Apollo Observations: 928
Orbital Period · P
2.92 yr
v(q)
36.9 km/s
v(Q)
11.8 km/s
Diameter · ≈
0.62 km
TJ
3.59
Eccentricity · e
0.5171

Orbit and dynamics

The path is an ellipse reaching 0.987 AU from the Sun at perihelion and 3.102 AU at aphelion, a radial span of 2.115 AU.

Applying Kepler's third law to a = 2.045 AU gives an orbital period of 2.92 yr, or about 1,068 days.

The high eccentricity (0.517) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

The orbital plane is tilted 12.7° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 36.9 km/s at perihelion and falls to 11.8 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 = 18.8 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.62 km.

Observation record and orbit quality

The current orbit solution is based on 928 observations and has a weighted RMS residual of 0.2884 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
2.045 AU
Eccentricity
0.5171
Perihelion
0.987 AU
Aphelion
3.10247 AU
Inclination
12.7°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
79.92°

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
18.8

Orbit Quality

RMS
0.2884
Condition
0
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.