SpaceAtlas Space Object Data
NASA JPL SBDB · 2011 EL51

2011 EL51

2011 EL51 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.191 AU it takes 1.30 yr to circle the Sun.

Apollo Observations: 49
Orbital Period · P
1.30 yr
v(q)
52 km/s
v(Q)
14.3 km/s
Diameter · ≈
0.15 km
TJ
5.14
Eccentricity · e
0.5688

Orbit and dynamics

The path is an ellipse reaching 0.514 AU from the Sun at perihelion and 1.868 AU at aphelion, a radial span of 1.354 AU.

Applying Kepler's third law to a = 1.191 AU gives an orbital period of 1.30 yr, or about 475 days.

The high eccentricity (0.569) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

The orbital plane is tilted 10.97° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 52 km/s at perihelion and falls to 14.3 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 = 21.9 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.15 km.

Observation record and orbit quality

The current orbit solution is based on 49 observations and has a weighted RMS residual of 0.5805 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
1.191 AU
Eccentricity
0.5688
Perihelion
0.514 AU
Aphelion
1.868441 AU
Inclination
10.97°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
203.31°

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
2037-Apr-02 11:16 0.173964 AU
26024713 km
14.60 km/s
2038-Nov-07 04:48 0.113354 AU
16957579 km
21.83 km/s
2051-Nov-10 23:00 0.177269 AU
26519071 km
24.08 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
21.9

Orbit Quality

RMS
0.58054
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.

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