If the dark nebula are really dark, how do we know they are there?
What will be an ideal response?
In some cases, they are not thick enough to block all light, so allow some red light through. Even if dense enough, they can still be seen in profile against rich star fields that lie behind them in the plane of the Milky Way.
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The ____ of a telescope is a measure of its ability to show fine detail and depends on the diameter of the objective
a. light-gathering power b. focal length c. magnifying power d. resolving power e. spherical aberration
What is the conversion factor between km/h and m/s?
A) 7.72 × 10-5 m/s B) 2.78 × 10-1 m/s C) 1.30 × 104 m/s D) 3.60 m/s E) 16.7 m/s
The seriousness of an asteroid collision is gauged by the ______________ scale
Fill in the blank(s) with correct word
In an isobaric process
a. the volume remains constant. b. the temperature remains constant. c. the pressure remains constant. d. no heat is transferred between a system and its surroundings. e. the internal energy is constant.