SpaceAtlas Space Object Data
NASA JPL SBDB · 2021 NW

2021 NW

2021 NW is an Amor-type near-Earth asteroid that approaches Earth from beyond our orbit without crossing it, orbiting the Sun at 2.253 AU once every 3.38 yr.

Amor Observations: 38
Orbital Period · P
3.38 yr
v(q)
32.7 km/s
v(Q)
12 km/s
Diameter · ≈
0.1 km
TJ
3.46
Eccentricity · e
0.4624

Orbit and dynamics

The path is an ellipse reaching 1.211 AU from the Sun at perihelion and 3.295 AU at aphelion, a radial span of 2.084 AU.

Applying Kepler's third law to a = 2.253 AU gives an orbital period of 3.38 yr, or about 1,235 days.

The high eccentricity (0.462) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

The orbital plane is tilted 10.08° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 32.7 km/s at perihelion and falls to 12 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 = 22.72 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.1 km.

Observation record and orbit quality

The current orbit solution is based on 38 observations and has a weighted RMS residual of 0.455 arcseconds.

Condition code U = 6 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
2.253 AU
Eccentricity
0.4624
Perihelion
1.211 AU
Aphelion
3.294787 AU
Inclination
10.08°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
155.35°

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
2048-Jul-10 03:16 0.235419 AU
35218222 km
6.00 km/s
2065-Jul-14 09:19 0.186568 AU
27910140 km
10.70 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
22.72

Orbit Quality

RMS
0.45496
Condition
6
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.

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