Observing the Universe Flashcards

All 6 cards in this deck

How were the stars and planets first observed, before telescopes were invented?

With the naked eye.

What advantage do telescopes have over the naked eye for observing the Universe?

They collect more light, so fainter and more distant objects can be seen in greater detail.

Apart from visible light, name two types of electromagnetic radiation used by modern telescopes to observe the Universe.

Any two of: radio, microwave, infrared, ultraviolet, X-ray, gamma.

Why are some telescopes placed outside the Earth's atmosphere?

The atmosphere absorbs much of the radiation (e.g. X-rays, UV, some infrared) and distorts/blurs the light that does get through.

Give one advantage, other than the atmosphere absorbing radiation, of a space telescope over a ground-based one.

No light pollution or cloud, and no atmospheric distortion, so images are clearer.

True or false? All types of electromagnetic radiation from space reach the Earth's surface.

False. The atmosphere absorbs much of it, e.g. X-rays and most ultraviolet, so those telescopes must be in space.