Search results
Results from the WOW.Com Content Network
Extra-close oppositions of Mars happen every 15 to 17 years, when we pass between Mars and the Sun around the time of its perihelion (closest point to the Sun in orbit). The minimum distance between Earth and Mars has been declining over the years, and in 2003 the minimum distance was 55.76 million km, nearer than any such encounter in almost ...
In gravitationally bound systems, the orbital speed of an astronomical body or object (e.g. planet, moon, artificial satellite, spacecraft, or star) is the speed at which it orbits around either the barycenter (the combined center of mass) or, if one body is much more massive than the other bodies of the system combined, its speed relative to the center of mass of the most massive body.
An areostationary orbit, areosynchronous equatorial orbit (AEO), or Mars geostationary orbit is a circular areosynchronous orbit (ASO) approximately 17,032 km (10,583 mi) in altitude above the Mars equator and following the direction of Mars's rotation. An object in such an orbit has an orbital period equal to Mars's rotational period, and so ...
Inversely, for calculating the distance where a body has to orbit in order to have a given orbital period T: a = G M T 2 4 π 2 3 {\displaystyle a={\sqrt[{3}]{\frac {GMT^{2}}{4\pi ^{2}}}}} For instance, for completing an orbit every 24 hours around a mass of 100 kg , a small body has to orbit at a distance of 1.08 meters from the central body's ...
All bounded orbits where the gravity of a central body dominates are elliptical in nature. A special case of this is the circular orbit, which is an ellipse of zero eccentricity. The formula for the velocity of a body in a circular orbit at distance r from the center of gravity of mass M can be derived as follows:
Neither the linear speed nor the angular speed of the planet in the orbit is constant, but the area speed (closely linked historically with the concept of angular momentum) is constant. The eccentricity of the orbit of the Earth makes the time from the March equinox to the September equinox , around 186 days, unequal to the time from the ...
Nodal precession is rotation of a planet's orbital plane. Nodal precession is more easily seen as distinct from periastron precession when the orbital plane is inclined to the star's rotation, the extreme case being a polar orbit. WASP-33 is a fast-rotating star that hosts a hot Jupiter in an almost polar orbit.
In astrodynamics, an orbit equation defines the path of orbiting body around central body relative to , without specifying position as a function of time.Under standard assumptions, a body moving under the influence of a force, directed to a central body, with a magnitude inversely proportional to the square of the distance (such as gravity), has an orbit that is a conic section (i.e. circular ...