SpaceAtlas Space Object Data
NASA JPL SBDB · 2015 XP378

2015 XP378

2015 XP378 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 3.22 AU it takes 5.78 yr to circle the Sun.

Apollo Observations: 84
Orbital Period · P
5.78 yr
v(q)
47.5 km/s
v(Q)
5.8 km/s
Diameter · ≈
0.62 km
TJ
2.54
Eccentricity · e
0.7822

Orbit and dynamics

The path is an ellipse reaching 0.701 AU from the Sun at perihelion and 5.739 AU at aphelion, a radial span of 5.038 AU.

Applying Kepler's third law to a = 3.22 AU gives an orbital period of 5.78 yr, or about 2,110 days.

The high eccentricity (0.782) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

A steep inclination of 20.3° carries it well above and below the ecliptic plane.

By the vis-viva equation its orbital speed rises to 47.5 km/s at perihelion and falls to 5.8 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 = 18.78 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.62 km.

Observation record and orbit quality

The current orbit solution is based on 84 observations and has a weighted RMS residual of 0.558 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
3.22 AU
Eccentricity
0.7822
Perihelion
0.701 AU
Aphelion
5.738684 AU
Inclination
20.3°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
264.47°

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
2045-Jul-21 13:56 0.439813 AU
65795079 km
30.27 km/s
2051-May-23 09:17 0.371826 AU
55624397 km
15.94 km/s
2057-Mar-08 21:40 0.218637 AU
32707608 km
18.24 km/s
2063-Feb-26 06:27 0.127412 AU
19060534 km
18.82 km/s
2069-Mar-07 22:02 0.196381 AU
29378189 km
17.70 km/s
2075-May-05 11:28 0.353367 AU
52862927 km
16.52 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
18.78

Orbit Quality

RMS
0.55801
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

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