Exam 6: The Tools of the Astronomer

The angular resolution of the largest single-dish radio telescope in the United States, the 100-m Green Bank Telescope, is _________ when it operates at a wavelength of 20 cm.

Explain the difference between dispersion and diffraction. How can both phenomena be used to create a spectrum?

Before CCDs were invented, what was the device most commonly used for imaging with optical telescopes?

Remote sensing instruments have been used to:

In 2009, the Cassini spacecraft made repeated orbits around Titan, Saturn's largest moon. If this spacecraft orbited at an altitude of 1,000 km above Titan's surface and its high-resolution camera had an angular resolution of 3 arcsec, how large an object could be resolved on Titan's surface?

How much larger is the light-gathering power of a 10-inch telescope than the human eye?

Explain why stars twinkle when viewed from the ground. Would they twinkle if viewed from outer space?

Label the eyepiece, lens, focus, and focal length of the telescope below.

Explain why chromatic aberration is a problem for refracting mirrors but not reflecting mirrors.

Cameras that use adaptive optics provide higher spatial resolution images primarily because:

The 305-m Arecibo radio telescope has a resolution that is no better than that of the human eye.

Astronomers can use ground-based telescopes to observe in the majority of which of the following parts of the electromagnetic spectrum?

Photography provides an improvement over naked-eye observations because:

The Voyager I spacecraft is currently 18 billion km from Earth and heading out of our Solar System. How long does it take radio messages from Voyager I to reach us?

In practice, the smallest angular size that one can resolve with a 10-inch telescope is governed by the:

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

Particle accelerators that smash atoms or particles together at high speeds, such as the LHC, are important tools used for simulating conditions in:

Why can a compound lens combat a refracting telescope's chromatic aberration?

Which of the following was NOT discovered by Galileo using a telescope?

How does the resolution of a telescope depend on its focal length?