Ida is the first known asteroid that to be discovered that has a moon called Dactyl. The smaller object in the picture is probably Dactyl. Twitter. The number 243 refers to the fact that it was the 243rd asteroid to be discovered since they were first discovered at the beginning of the 19th Century.
It was only in February 1994 that the discovery of a moon orbiting an asteroid was released to the public. The discovery had been made after studying pictures that had been taken of the asteroid on August 28th the preceeding year. Federal University of Rio Grande, Brazil
Ida was named after a nymph in Greek mythology who was tasked with looking after a young infant Zeus with her sister Adrasteia. The Dactyl comes from the mythical creatures that lived on Mount Ida on the island of Crete. Ref: N.A.S.A.
Ida is an asteroid, a large rock that orbits the Sun mainly between the orbits of Mars and Jupiter. They tend to be an irregular shaped but Ceres asteroid is known to be spherical in shape but because it doesn't clear its path round the Sun, it is only a dwarf planet. Its mass is estimated/calculated at being 100. Its orbit takes 4.84 years to travel round the Sun. Its takes 4.633 hours to do a full rotation period.
The absolute magnitude of the object is 0 which is the brightness of the object. A higher absolute magnitude means that the object is faint whereas a very low number means it is very bright.
The Semi-Major Axis of the orbit is 2.861, which is the furthest point from the centre to the edge of an elliptical point.
The approximate diameter of Ida is 0 in km. The mass of the object is calculated at being 100 kg (10^15).
The orbital inclination, the angle at which Ida orbits in relation to the orbital plane is 1.14 degrees. The orbital eccentricity is 0.0451, it is the degree at which Ida orbits close to a circular (0) orbit as opposed to an elliptical (1) orbit.
|Rotation Period||4.633 Hours|
|Mass||100 kg (10^15)|