77P/Longmore is a mid-sized comet whose orbit features a relatively short period, low inclination, and is controlled by Jupiter's gravitational effects. NASA JPL has not classified 77P/Longmore as potentially hazardous because its orbit does not bring it close to Earth.
77P/Longmore orbits the sun every 2,510 days (6.87 years), coming as close as 2.33 AU and reaching as far as 4.89 AU from the sun. 77P/Longmore is about 8.2 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the San Francisco Bay.
77P/Longmore's orbit is 1.34 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.
77P/Longmore's orbit is determined by observations dating back to Aug. 11, 1975. It was last officially observed on Aug. 5, 2023. The IAU Minor Planet Center records 2,509 observations used to determine its orbit.
The position of 77P/Longmore 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.