Exam 6: The Tools of the Astronomer

According to the law of reflection, if a beam of light strikes a flat mirror at an angle of 30° relative to a plane perpendicular to the surface of the mirror, at what angle will it reflect, relative to a plane perpendicular to the surface of the mirror?

How faint an object we can see with our eyes is limited only by the integration time of our eye (how often it processes input).

Which of the following phenomena is shown in the figure below?

Discuss two tools that modern astronomers use to explore the cosmos that are different from traditional optical telescopes and give an example of how and why each is used.

The major advantage CCDs have over other imaging techniques is that:

The dispersing element in a spectrograph could be a prism or a diffraction grating.

Which of the following is the biggest disadvantage of putting a telescope in space?

Typically, video is shot using 24 to 30 frames per second (one frame each 33 to 42 ms). If a filmmaker shot new experimental video at 100 frames per second (one frame each 1 ms), how would it look during playback to the human eye?

Astronomers usually study distant galaxies by looking at them directly through the eyepiece of a telescope.

Samples of which celestial object(s) have been brought back to Earth to be studied in detail?

Name two reasons why astronomers might use a space telescope over a ground-based telescope.

Why do reflecting telescopes usually have a secondary mirror in addition to a primary mirror?

A beam of light passes from air to water at an incident angle of 40°, relative to a plane perpendicular to the boundary between the two. At what angle will it emerge into the water, relative to a plane perpendicular to the boundary?

The diffraction limit of a 4-meter telescope is _________ than that of a 2-meter telescope.

Label the eyepiece, primary mirror, secondary mirror, focus, and focal length of the telescope below.

NASA's Kuiper Airborne Observatory and SOFIA are two examples of telescopes placed in high-flying aircraft. Why would astronomers put telescopes in airplanes?

In 2008, the Cassini spacecraft made a flyby of Enceladus, one of the icy moons of Saturn. If the spacecraft's high resolution camera had an angular resolution of 3 arcsec, and it flew at an altitude of 23 km above Enceladus's surface, how large an object could be resolved on the surface?

What is the angular resolution of a 1-m, ground-based, optical telescope that observes at a wavelength of 600 nm compared to that of a 300-ft, single-dish radio telescope that observes at a wavelength of 21 cm?

Hans Lippershey invented the telescope in the early 1600s.

The angular resolution of a ground-based telescope (without adaptive optics) is typically: