- Accumulation of dust and gas into larger bodies.
Adams, John Couch 1819-1892
- English astronomer and mathematician. At the age of 24, Adams was
the first person to predict the position of a planetary mass beyond
Uranus. After Johann Gottfried Galle confirmed the existence of Neptune
based on independent calculations done by Urbain Jean Joseph
Le Verrier, the two became embroiled in
a dispute over priority.
- Reflectivity of an object; ratio of reflected light to incident light.
- A dark or light marking on the surface of an object
that might not be a geological or topographical feature.
- (1) Material that is formed or introduced from somewhere other
than the place it is presently found. (2) Fragmented rock thrown
out of the crater during its formation that either falls back to
partly fill the crater or blankets its outer flanks after the impact
- The closest bright star to our solar system.
- A unit of length = 1.0E-08cm.
- The point that is directly on the opposite side of the planet; e.g., the
Earth's north pole is antipodal to its south pole.
- The point in its orbit where a planet is farthest from the Sun.
- The point in orbit farthest from the planet.
- The point in orbit farthest from the Earth.
- The fine-grained material produced by a
pyroclastic eruption. An ash
particle is defined to have a diameter of less than 2 millimeters.
- Asteroids are assigned a serial number when they are discovered;
it has no particular meaning except that asteroid N+1 was discovered
after asteroid N.
astronomical unit (AU)
- The average distance from the Earth to the Sun;
1 AU is 149,597,870 kilometers (92,960,116 miles).
- One atmosphere is 14.7 pounds per square inch;
standard atmospheric pressure at sea level on Earth.
- A glow in a planet's ionosphere caused by the interaction between the
planet's magnetic field and charged particles from the Sun.
- The Northern Lights caused by the interaction between the
solar wind, the Earth's magnetic field and the upper atmosphere;
a similar effect happens in the southern hemisphere where it is known as
the aurora australis.