SpaceAtlas Space Object Data
NASA JPL SBDB · 2018 ER1

2018 ER1

2018 ER1 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.01 AU it takes 1.02 yr to circle the Sun.

Apollo Observations: 63
Orbital Period · P
1.02 yr
v(q)
32.5 km/s
v(Q)
27 km/s
Diameter · ≈
0.03 km
TJ
6.02
Eccentricity · e
0.0924

Orbit and dynamics

Between its closest point (0.917 AU) and its farthest (1.103 AU), the heliocentric distance changes by 0.186 AU over every revolution.

One full revolution takes 1.02 yr (371 days), computed from the semi-major axis of 1.01 AU.

With e = 0.092, the orbit is close to circular.

The orbital plane is tilted 6.39° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 32.5 km/s at perihelion and falls to 27 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 = 25.72 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.03 km.

Observation record and orbit quality

Astrometry from 63 individual observations underpins this orbit; the fit leaves an RMS residual of 0.4733 arcseconds.

Condition code U = 5 indicates a moderately constrained orbit; predictions decades ahead still carry noticeable uncertainty.

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
1.01 AU
Eccentricity
0.0924
Perihelion
0.917 AU
Aphelion
1.103324 AU
Inclination
6.39°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
299.76°

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-Oct-26 05:04 0.405544 AU
60668517 km
15.78 km/s
2079-Mar-22 14:12 0.424643 AU
63525632 km
16.67 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
25.72

Orbit Quality

RMS
0.47335
Condition
5
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.