SpaceAtlas Space Object Data
NASA JPL SBDB · 257744

257744

257744 belongs to the Apollo group of near-Earth asteroids, whose orbits cross the path of Earth; with a semi-major axis of 1.695 AU it takes 2.21 yr to circle the Sun.

Apollo Observations: 554
Orbital Period · P
2.21 yr
v(q)
44.8 km/s
v(Q)
11.7 km/s
Diameter · ≈
0.67 km
TJ
3.99
Eccentricity · e
0.586

Orbit and dynamics

The path is an ellipse reaching 0.702 AU from the Sun at perihelion and 2.688 AU at aphelion, a radial span of 1.986 AU.

Applying Kepler's third law to a = 1.695 AU gives an orbital period of 2.21 yr, or about 806 days.

The high eccentricity (0.586) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

The orbital plane is tilted 7.92° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 44.8 km/s at perihelion and falls to 11.7 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 = 18.61 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.67 km.

Observation record and orbit quality

The current orbit solution is based on 554 observations and has a weighted RMS residual of 0.4539 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
1.695 AU
Eccentricity
0.586
Perihelion
0.702 AU
Aphelion
2.68827 AU
Inclination
7.92°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
30.51°

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
2074-Nov-21 15:33 0.157142 AU
23508042 km
14.23 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
18.61

Orbit Quality

RMS
0.45388
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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