SpaceAtlas Space Object Data
NASA JPL SBDB · 1991 BA

1991 BA

1991 BA belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 2.189 AU it takes 3.24 yr to circle the Sun.

Apollo Observations: 7
Orbital Period · P
3.24 yr
v(q)
45.6 km/s
v(Q)
8.9 km/s
Diameter · ≈
0.01 km
TJ
3.34
Eccentricity · e
0.6732

Orbit and dynamics

Between its closest point (0.715 AU) and its farthest (3.663 AU), the heliocentric distance changes by 2.948 AU over every revolution.

One full revolution takes 3.24 yr (1,183 days), computed from the semi-major axis of 2.189 AU.

The high eccentricity (0.673) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

Its inclination of 1.94° keeps it close to the plane of the ecliptic.

By the vis-viva equation its orbital speed rises to 45.6 km/s at perihelion and falls to 8.9 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 = 28.6 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.01 km.

Observation record and orbit quality

Astrometry from 7 individual observations underpins this orbit; the fit leaves an RMS residual of 0.0732 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
2.189 AU
Eccentricity
0.6732
Perihelion
0.715 AU
Aphelion
3.662635 AU
Inclination
1.94°
Orbital Period
— yr
Epoch
2448274.5
Mean Anomaly
346.84°

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
28.6

Orbit Quality

RMS
0.073238
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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