Near-Earth object NEOs pass Earth closer than the distance of the Moon. On August 10, 1972, a meteor that became known as the 1972 Great Daylight Fireball was witnessed by many people; it moved north over the Rocky Mountains from the U.S. Southwest to Canada. It was an Earth-grazing meteoroid that passed within of the Earth's surface, and was filmed by a tourist at the Grand Teton National Park in Wyoming with an 8-millimeter color movie camera. On October 13, 1990, Earth-grazing meteoroid EN131090 was observed above Czechoslovakia and Poland, moving at along a trajectory from south to north. The closest approach
Earth-centered inertial the orientation of the Earth's rotational axis in space. The Earth's orbit plane is called the ecliptic, and it does not coincide with the Earth's equatorial plane. The angle between the Earth's equatorial plane and the ecliptic, "ε", is called the obliquity of the ecliptic and "ε" ≈ 23.4°. An equinox occurs when the earth is at a position in its orbit such that a vector from the earth toward the sun points to where the ecliptic intersects the celestial equator. The equinox which occurs near the first day of spring (with respect to the North hemisphere) is called the