SpaceAtlas Space Object Data
NASA JPL SBDB · 2018 DJ

2018 DJ

2018 DJ belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 2.14 AU it takes 3.13 yr to circle the Sun.

Apollo Observations: 90
Orbital Period · P
3.13 yr
v(q)
50 km/s
v(Q)
8.3 km/s
Diameter · ≈
0.19 km
TJ
3.31
Eccentricity · e
0.7157

Orbit and dynamics

Between its closest point (0.608 AU) and its farthest (3.672 AU), the heliocentric distance changes by 3.064 AU over every revolution.

One full revolution takes 3.13 yr (1,143 days), computed from the semi-major axis of 2.14 AU.

The high eccentricity (0.716) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

The orbital plane is tilted 9.84° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 50 km/s at perihelion and falls to 8.3 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 = 21.41 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.19 km.

Observation record and orbit quality

Astrometry from 90 individual observations underpins this orbit; the fit leaves an RMS residual of 0.6295 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
2.14 AU
Eccentricity
0.7157
Perihelion
0.608 AU
Aphelion
3.671598 AU
Inclination
9.84°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
212.04°

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
2043-Apr-05 17:46 0.282073 AU
42197565 km
14.51 km/s
2046-Jul-20 20:33 0.352236 AU
52693708 km
17.55 km/s
2049-Sep-26 12:41 0.356424 AU
53320289 km
32.32 km/s
2068-Mar-17 12:41 0.139392 AU
20852680 km
18.68 km/s
2071-Jun-20 15:52 0.426862 AU
63857697 km
21.07 km/s
2074-Sep-14 19:49 0.142746 AU
21354482 km
25.50 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
21.41

Orbit Quality

RMS
0.62947
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.