SpaceAtlas Space Object Data
NASA JPL SBDB · 2021 SC2

2021 SC2

2021 SC2 is an Aten-type near-Earth asteroid whose orbit lies mostly inside that of Earth, with a semi-major axis of 0.971 AU and a period of 0.96 yr.

Aten Observations: 25
Orbital Period · P
0.96 yr
v(q)
39.8 km/s
v(Q)
23 km/s
Diameter · ≈
0.04 km
TJ
6.13
Eccentricity · e
0.2673

Orbit and dynamics

The path is an ellipse reaching 0.711 AU from the Sun at perihelion and 1.231 AU at aphelion, a radial span of 0.52 AU.

Applying Kepler's third law to a = 0.971 AU gives an orbital period of 0.96 yr, or about 349 days.

An eccentricity of 0.267 makes the orbit moderately elongated.

A steep inclination of 21.71° carries it well above and below the ecliptic plane.

By the vis-viva equation its orbital speed rises to 39.8 km/s at perihelion and falls to 23 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 = 24.73 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.04 km.

Observation record and orbit quality

The current orbit solution is based on 25 observations and has a weighted RMS residual of 0.5139 arcseconds.

Condition code U = 7 signals a poorly constrained orbit, so its future path should be treated as provisional.

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
0.971 AU
Eccentricity
0.2673
Perihelion
0.711 AU
Aphelion
1.230548 AU
Inclination
21.71°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
219.04°

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
2039-May-28 20:27 0.361160 AU
54028756 km
20.31 km/s
2043-Oct-07 09:25 0.086231 AU
12899981 km
11.86 km/s
2044-Oct-07 10:23 0.085258 AU
12754422 km
15.91 km/s
2045-Sep-30 12:36 0.298033 AU
44585121 km
22.33 km/s
2066-Oct-09 05:38 0.072551 AU
10853438 km
13.42 km/s
2067-Oct-05 06:26 0.173169 AU
25905682 km
18.96 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
24.73

Orbit Quality

RMS
0.51394
Condition
7
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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