Parthenope is a very large asteroid circling the sun between Mars and Jupiter, inside the main asteroid belt. NASA JPL does not treat Parthenope as potentially hazardous, because its orbit never carries it near Earth.
One lap around the sun takes Parthenope 1,400 days (3.83 years). Over that circuit it swings between 2.21 AU and 2.7 AU from the sun, travelling at an average of 19.06 km/s. At 142.9 kilometers across, Parthenope is bigger than 99% of known asteroids — roughly the size of the U.S. state of Connecticut.
Parthenope has been watched long enough to time its spin: one full turn on its axis takes 13.72 hours.
Parthenope is classed as S on the Tholen scale, Sk on SMASSII.
At their nearest, the orbits of Parthenope and Earth stay 1.2 AU apart. That is a comfortable margin, and it holds at every point in the orbit.
Orbital simulations run by NASA JPL's CNEOS turn up no close approaches to Earth.
The orbit of Parthenope is pinned down by sightings going back to Sept. 17, 1850, the most recent officially logged on June 1, 2023. The IAU Minor Planet Center holds 10,049 observations behind that solution.
A ◯ pink circle marks where Parthenope sits. It may fall outside your current field of view — use the controls below to change the position, location and time.