SpaceAtlas Space Object Data
NASA JPL SBDB · 2011 UT91

2011 UT91

2011 UT91 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.363 AU it takes 1.59 yr to circle the Sun.

Apollo Observations: 52
Orbital Period · P
1.59 yr
v(q)
39.4 km/s
v(Q)
16.5 km/s
Diameter · ≈
0.09 km
TJ
4.73
Eccentricity · e
0.4098

Orbit and dynamics

Between its closest point (0.805 AU) and its farthest (1.922 AU), the heliocentric distance changes by 1.117 AU over every revolution.

One full revolution takes 1.59 yr (581 days), computed from the semi-major axis of 1.363 AU.

The high eccentricity (0.41) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

The orbital plane is tilted 13.56° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 39.4 km/s at perihelion and falls to 16.5 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

No direct size measurement is available; from an absolute magnitude of H = 23.03 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.09 km.

Observation record and orbit quality

Astrometry from 52 individual observations underpins this orbit; the fit leaves an RMS residual of 0.3639 arcseconds.

Condition code U = 7 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
1.363 AU
Eccentricity
0.4098
Perihelion
0.805 AU
Aphelion
1.921557 AU
Inclination
13.56°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
24.83°

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
23.03

Orbit Quality

RMS
0.36388
Condition
7
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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