A heliocentric orbit (also called circumsolar orbit) is an orbit around the Sun. All planets, comets, and asteroids in our Solar System are in such orbits, as are many artificial probes and pieces of debris. The moons of planets in the Solar System, by contrast, are not in heliocentric orbits as they orbit their respective planet.
While it is convenient to think of orbits around the Sun, bodies in the Solar System do not actually orbit the Sun. Instead, all bodies in the Solar System (including the Sun) actually orbit the barycenter of the Solar System. A similar phenomenon allows the detection of extrasolar planets by way of the radial velocity method.
The helio- prefix is derived from the ancient Greek word helios, meaning "sun", and also Helios, the personification of the Sun in Greek mythology.
Famous quotes containing the word orbit:
““To my thinking” boomed the Professor, begging the question as usual, “the greatest triumph of the human mind was the calculation of Neptune from the observed vagaries of the orbit of Uranus.”
“And yours,” said the P.B.”
—Samuel Beckett (1906–1989)