SpaceAtlas Space Object Data
NASA JPL SBDB · 154555

154555

154555 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.185 AU it takes 1.29 yr to circle the Sun.

Apollo Observations: 1,892
Orbital Period · P
1.29 yr
v(q)
53.1 km/s
v(Q)
14.1 km/s
Diameter · ≈
1.62 km
TJ
5.01
Eccentricity · e
0.5804

Orbit and dynamics

Between its closest point (0.497 AU) and its farthest (1.873 AU), the heliocentric distance changes by 1.376 AU over every revolution.

One full revolution takes 1.29 yr (471 days), computed from the semi-major axis of 1.185 AU.

The high eccentricity (0.58) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

A steep inclination of 36.82° carries it well above and below the ecliptic plane.

By the vis-viva equation its orbital speed rises to 53.1 km/s at perihelion and falls to 14.1 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 = 16.7 and an assumed geometric albedo of 0.14, the diameter works out to roughly 1.62 km.

Observation record and orbit quality

Astrometry from 1,892 individual observations underpins this orbit; the fit leaves an RMS residual of 0.5698 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
1.185 AU
Eccentricity
0.5804
Perihelion
0.497 AU
Aphelion
1.872774 AU
Inclination
36.82°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
247.51°

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
2047-May-02 10:11 0.159616 AU
23878168 km
29.01 km/s
2056-May-07 23:44 0.115956 AU
17346752 km
26.14 km/s
2065-May-14 22:56 0.184746 AU
27637548 km
23.47 km/s
2066-Nov-28 01:33 0.195765 AU
29286031 km
27.59 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
16.7

Orbit Quality

RMS
0.56979
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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