SWAN

Orbit and dynamics

The path is an ellipse reaching 0.649 AU from the Sun at perihelion and 17.999 AU at aphelion, a radial span of 17.35 AU.

Applying Kepler's third law to a = 9.324 AU gives an orbital period of 28.5 yr, or about 10,399 days.

The high eccentricity (0.93) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

A steep inclination of 160.0° carries it well above and below the ecliptic plane.

By the vis-viva equation its orbital speed rises to 51.4 km/s at perihelion and falls to 1.9 km/s at aphelion.

Because q < 1 AU and Q > 1 AU, this orbit geometrically intersects the region of Earth's orbit.

Its Tisserand parameter with respect to Jupiter is T_J = -0.36, a standard discriminator between asteroidal and cometary dynamics.

Size and surface

Neither a measured diameter nor a reliable absolute magnitude is available for SWAN, so its physical size remains unconstrained.

Observation record and orbit quality

The current orbit solution is based on 31 observations and has a weighted RMS residual of 0.671 arcseconds.

Condition code U = 8 signals a poorly constrained orbit, so its future path should be treated as provisional.