Astronomy Chapter 6 Module 6 HW2

Which of the following telescopes would benefit most from adaptive optics?

The Keck I Telescope on Mauna Kea.

Which of the following is not a reason why telescopes tend to be built on mountaintops that are relatively far from cities and are in regions with dry climates?

The thin air on mountaintops makes the glass in telescope mirrors less susceptible to warping.

Which of the following wavelength regions can be studied with telescopes on the ground?

radio, visible, and very limited portions of the infrared and ultraviolet regions

Which of the following is not an advantage of the Hubble Space Telescope over ground-based telescopes?

****it is closer to the stars. Stars do not twinkle when observed from space. It can observe infrared and ultraviolet light, as well as visible light. It never has to close because of bad weather. Observers on the ground can use it at any time of day (i.e., not only during their night).

At which wavelength range is there no current or planned space observatory?

***radio infrared visible X-ray gamma-ray

Which of the following statements are true? (mark all that apply)

Adaptive optics corrects for atmospheric distortion by following the distortion of a bright star, possibly an artificial star created by a laser, and rapidly changing the shape of a mirror using computer-controlled actuators to compensate for the distortion. X rays from astronomical objects can only be detected from telescopes in space or in high altitude rockets. The best observing sites for optical telescopes are atop remote mountains.

What do astronomers mean by light pollution?

Light pollution refers to light used for human activities that brightens the sky and hinders astronomical observations.

Which of the following proposals would you fund? Mark all that you would.

Ultraviolet telescope in orbit around Earth

The Chandra X-Ray Observatory must operate in space because

X rays do not penetrate Earth's atmosphere.

What is an artificial star?

a point of light in Earth's atmosphere created by a laser for the purpose of monitoring atmospheric fluctuations

What causes stars to twinkle?

bending of light rays by turbulent layers in the atmosphere

The best ground-based sites for astronomical observing are:

calm high dark dry

What is the purpose of adaptive optics?

to eliminate the distorting effects of atmospheric turbulence for telescopes on the ground

Which of the following is not a good reason to place observatories on remote mountain tops?

to reduce light pollution to reduce light distortion to reduce light absorption *****to be able to observe at radio wavelengths to be able to observe at infrared wavelengths

The stars in our sky twinkle in brightness and color because of

turbulence in the Earth's atmosphere.

Which of the following wavelength regions cannot be studied with telescopes on the ground?

ultraviolet and x-rays