SpaceAtlas Space Object Data
NASA JPL SBDB · 2015 XK55

2015 XK55

2015 XK55 is an Aten-type near-Earth asteroid whose orbit lies mostly inside that of Earth, with a semi-major axis of 0.899 AU and a period of 0.85 yr.

Aten Observations: 40
Orbital Period · P
0.85 yr
v(q)
38.3 km/s
v(Q)
25.8 km/s
Diameter · ≈
0.04 km
TJ
6.59
Eccentricity · e
0.1955

Orbit and dynamics

The path is an ellipse reaching 0.724 AU from the Sun at perihelion and 1.075 AU at aphelion, a radial span of 0.351 AU.

Applying Kepler's third law to a = 0.899 AU gives an orbital period of 0.85 yr, or about 312 days.

An eccentricity of 0.196 makes the orbit moderately elongated.

The orbital plane is tilted 9.15° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 38.3 km/s at perihelion and falls to 25.8 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 = 24.5 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.04 km.

Observation record and orbit quality

The current orbit solution is based on 40 observations and has a weighted RMS residual of 0.3782 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
0.8995 AU
Eccentricity
0.1955
Perihelion
0.724 AU
Aphelion
1.075352 AU
Inclination
9.15°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
319.46°

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
2027-May-28 02:50 0.286207 AU
42816017 km
10.28 km/s
2027-Dec-30 23:25 0.240329 AU
35952696 km
13.26 km/s
2032-Oct-10 02:25 0.157942 AU
23627731 km
9.70 km/s
2033-Apr-29 15:12 0.283305 AU
42381826 km
9.87 km/s
2033-Dec-25 00:50 0.412745 AU
61745837 km
19.15 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
24.5

Orbit Quality

RMS
0.37816
Condition
7
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

Explore asteroids, comets and near-Earth objects with JPL orbital data.