SpaceAtlas Space Object Data
NASA JPL SBDB · 2017 OT18

2017 OT18

2017 OT18 is an Amor-type near-Earth asteroid that approaches Earth from beyond our orbit without crossing it, orbiting the Sun at 2.328 AU once every 3.55 yr.

Amor Observations: 215
Orbital Period · P
3.55 yr
v(q)
32.4 km/s
v(Q)
11.7 km/s
Diameter · ≈
0.51 km
TJ
3.34
Eccentricity · e
0.4683

Orbit and dynamics

Between its closest point (1.238 AU) and its farthest (3.418 AU), the heliocentric distance changes by 2.18 AU over every revolution.

One full revolution takes 3.55 yr (1,297 days), computed from the semi-major axis of 2.328 AU.

The high eccentricity (0.468) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

A steep inclination of 21.06° carries it well above and below the ecliptic plane.

By the vis-viva equation its orbital speed rises to 32.4 km/s at perihelion and falls to 11.7 km/s at aphelion.

Its perihelion lies just outside Earth's orbit, which is why it is classed as Earth-approaching rather than Earth-crossing.

Size and surface

No direct size measurement is available; from an absolute magnitude of H = 19.23 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.51 km.

Observation record and orbit quality

Astrometry from 215 individual observations underpins this orbit; the fit leaves an RMS residual of 0.4449 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
2.328 AU
Eccentricity
0.4683
Perihelion
1.238 AU
Aphelion
3.418202 AU
Inclination
21.06°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
168.48°

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
2049-Aug-08 03:41 0.435533 AU
65154749 km
14.87 km/s
2056-Aug-02 13:33 0.481988 AU
72104432 km
10.57 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
19.23

Orbit Quality

RMS
0.44492
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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