SpaceAtlas Space Object Data
NASA JPL SBDB · 357P

Hill

Hill follows a distinctly cometary orbit: an eccentricity of 0.435 carries it from 2.512 AU at perihelion out to 6.388 AU at aphelion.

comet Observations: 298
Orbital Period · P
9.39 yr
v(q)
22.5 km/s
v(Q)
8.9 km/s
TJ
2.82
Eccentricity · e
0.4355

Orbit and dynamics

The path is an ellipse reaching 2.512 AU from the Sun at perihelion and 6.388 AU at aphelion, a radial span of 3.876 AU.

Applying Kepler's third law to a = 4.45 AU gives an orbital period of 9.39 yr, or about 3,429 days.

The high eccentricity (0.435) produces a strongly elongated orbit, so the object spends most of its time far from the Sun.

The orbital plane is tilted 6.33° relative to the ecliptic.

By the vis-viva equation its orbital speed rises to 22.5 km/s at perihelion and falls to 8.9 km/s at aphelion.

Its Tisserand parameter with respect to Jupiter is T_J = 2.82, a standard discriminator between asteroidal and cometary dynamics.

Size and surface

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

Observation record and orbit quality

The current orbit solution is based on 298 observations and has a weighted RMS residual of 0.6995 arcseconds.

Condition code U = 1 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
4.45 AU
Eccentricity
0.4355
Perihelion
2.512 AU
Aphelion
6.387975 AU
Inclination
6.33°
Orbital Period
— yr
Epoch
2455210.5
Mean Anomaly
40.52°

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

No close approaches to Earth are currently on record for this object.

Physical Parameters

Diameter
— km
Albedo
—
Density
— g/cm³
Rotation Period
— h
Absolute Magnitude
—

Orbit Quality

RMS
0.69945
Condition
1
Orbit ID
—
Data source: NASA JPL Small-Body Database . 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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