Visiting comets and asteroids: In recent years, several space probes have been sent to comets and asteroids to physically interact with them
Briefly describe three of these missions, and compare how each allows astronomers to better study the composition of these objects.
Stardust directly collected dust from a comet's tail and returned it to Earth, where the material can be studied in great detail in laboratories. Deep Impact, on the other hand, released material from deep inside a comet into space (using an impactor) where it could be examined via spectroscopy using Earth-based telescopes. The Rosetta mission will place a lander on the surface of a comet, where it can use instruments to directly study the material on the comet's surface.
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Identify a true statement about Venus
A) It is the largest planet in the Solar System. B) It is the least luminous object in the sky. C) It is more than 60 million miles away from the Sun. D) It generates its own energy by nuclear fusion.
A satellite revolves around the Earth in a circular orbit with a mechanical energy of 
J. What is its kinetic energy?
A.
B.
C.
D.
E.
The wavelength from an FM station broadcasting at 93.9 megahertz on your radio is
a. 31.3 m. b. 3.13 m. c. 0.313 m. d. 0.0313 m. e. none of the above.
A magnifying glass has a convex lens of focal length 15 cm. At what distance from a postage stamp should you hold this lens to get a magnification of +2.0?