Semele is a large asteroid orbiting between Mars and Jupiter in the main portion of the asteroid belt. NASA JPL has not classified Semele as potentially hazardous because its orbit does not bring it close to Earth.
Semele orbits the sun every 2,000 days (5.48 years), coming as close as 2.43 AU and reaching as far as 3.78 AU from the sun. Semele is about 109.9 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the U.S. state of Delaware.
The rotation of Semele has been observed. It completes a rotation on its axis every 16.63 hours.
Semele's spectral type C (Tholen) / None (SMASSII) indicates that it is likely to contain water, iron, nickel, cobalt, nitrogen, and ammonia.
Semele's orbit is 1.44 AU from Earth's orbit at its closest point. This means that there is an extremely wide berth between this asteroid and Earth at all times.
Orbital simulations conducted by NASA JPL's CNEOS do not show any close approaches to Earth.
Semele's orbit is determined by observations dating back to Dec. 29, 1871. It was last officially observed on June 30, 2023. The IAU Minor Planet Center records 4,261 observations used to determine its orbit.
The position of Semele is indicated by a ◯ pink circle. Note that the object may not be in your current field of view. Use the controls below to adjust position, location, and time.