SpaceAtlas Space Object Data
NASA JPL SBDB · 2011 BY18

2011 BY18

2011 BY18 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 2.263 AU it takes 3.40 yr to circle the Sun.

Apollo Observations: 101
Orbital Period · P
3.40 yr
v(q)
56.8 km/s
v(Q)
6.9 km/s
Diameter · ≈
0.24 km
TJ
3.12
Eccentricity · e
0.7832

Orbit and dynamics

The path is an ellipse reaching 0.491 AU from the Sun at perihelion and 4.035 AU at aphelion, a radial span of 3.544 AU.

Applying Kepler's third law to a = 2.263 AU gives an orbital period of 3.40 yr, or about 1,243 days.

The high eccentricity (0.783) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

Its inclination of 3.65° keeps it close to the plane of the ecliptic.

By the vis-viva equation its orbital speed rises to 56.8 km/s at perihelion and falls to 6.9 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 = 20.81 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.24 km.

Observation record and orbit quality

The current orbit solution is based on 101 observations and has a weighted RMS residual of 0.5526 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
2.263 AU
Eccentricity
0.7832
Perihelion
0.491 AU
Aphelion
4.035382 AU
Inclination
3.65°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
195.97°

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
2028-Feb-05 00:48 0.441646 AU
66069255 km
38.30 km/s
2034-Nov-11 17:16 0.450762 AU
67433037 km
22.30 km/s
2041-Jul-16 20:27 0.271132 AU
40560780 km
17.00 km/s
2052-Jan-01 07:21 0.217542 AU
32543803 km
18.14 km/s
2058-Sep-07 10:49 0.469954 AU
70304124 km
23.28 km/s
2065-Jun-08 12:24 0.381522 AU
57074853 km
35.96 km/s
2069-Jan-26 00:06 0.240900 AU
36038122 km
32.01 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
20.81

Orbit Quality

RMS
0.55264
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.

Keep exploring

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