Saturday, November 13, 2010

Weekly Vocabualry Words - 11/15/10

1. Alpha Centauri
The closest bright star to our solar system.
2. aurora
A glow in a planet's ionosphere caused by the interaction between the planet's magnetic field and charged particles from the Sun.
3. antipodal point
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.
4. aphelion
The point in its orbit where a planet is farthest from the Sun.
5. apoapsis
The point in orbit farthest from the planet.