SpaceAtlas Space Object Data
NASA JPL SBDB · 2021 JS1

2021 JS1

2021 JS1 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.674 AU it takes 2.17 yr to circle the Sun.

Apollo Observations: 32
Orbital Period · P
2.17 yr
v(q)
45.5 km/s
v(Q)
11.6 km/s
Diameter · ≈
0.01 km
TJ
3.92
Eccentricity · e
0.5927

Orbit and dynamics

The path is an ellipse reaching 0.682 AU from the Sun at perihelion and 2.666 AU at aphelion, a radial span of 1.984 AU.

Applying Kepler's third law to a = 1.674 AU gives an orbital period of 2.17 yr, or about 791 days.

The high eccentricity (0.593) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

A steep inclination of 27.84° carries it well above and below the ecliptic plane.

By the vis-viva equation its orbital speed rises to 45.5 km/s at perihelion and falls to 11.6 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 = 28.49 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.01 km.

Observation record and orbit quality

The current orbit solution is based on 32 observations and has a weighted RMS residual of 0.524 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
1.674 AU
Eccentricity
0.5927
Perihelion
0.682 AU
Aphelion
2.66618 AU
Inclination
27.84°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
103.84°

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
2034-May-04 09:24 0.000498 AU
74438 km
23.55 km/s
2036-Oct-21 01:44 0.193723 AU
28980601 km
16.97 km/s
2047-Apr-28 20:38 0.139756 AU
20907137 km
26.43 km/s
2049-Oct-18 23:44 0.401161 AU
60012848 km
15.11 km/s
2060-Apr-21 06:37 0.227067 AU
33968716 km
30.13 km/s
2064-Nov-18 05:48 0.372553 AU
55733204 km
34.73 km/s
2073-Apr-13 14:47 0.305598 AU
45716835 km
34.62 km/s
2077-Nov-10 18:27 0.134864 AU
20175363 km
29.74 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
28.49

Orbit Quality

RMS
0.52403
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.

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