SpaceAtlas Space Object Data
NASA JPL SBDB · 308635

308635

308635 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.157 AU it takes 1.24 yr to circle the Sun.

Apollo Observations: 4,013
Orbital Period · P
1.24 yr
v(q)
43.9 km/s
v(Q)
17.5 km/s
Diameter · ≈
0.15 km
TJ
5.35
Eccentricity · e
0.4306

Orbit and dynamics

Between its closest point (0.659 AU) and its farthest (1.655 AU), the heliocentric distance changes by 0.996 AU over every revolution.

One full revolution takes 1.24 yr (455 days), computed from the semi-major axis of 1.157 AU.

The high eccentricity (0.431) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

Its inclination of 0.34° keeps it close to the plane of the ecliptic.

By the vis-viva equation its orbital speed rises to 43.9 km/s at perihelion and falls to 17.5 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

The measured diameter is 0.4 km, a value from direct size determination rather than from brightness alone.

Observation record and orbit quality

Astrometry from 4,013 individual observations underpins this orbit; the fit leaves an RMS residual of 0.2267 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
1.157 AU
Eccentricity
0.4306
Perihelion
0.659 AU
Aphelion
1.655204 AU
Inclination
0.34°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
304.61°

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
0.4 km
Albedo
—
Density
— g/cm³
Rotation Period
— h
Absolute Magnitude
21.91

Orbit Quality

RMS
0.22669
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.

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