Download Telescopes

Telescopes
Stars are too far away to ever study directly. It would take 19,000 years to reach the
nearest star, a mere 4 light years away traveling at 240,000 km/hr (150,000 miles/hr) the
world record for current space travel speed! So all the evidence we gather about stars to
form our theories of the Universe comes in the form of the electromagnetic spectrum, or
in everyday words, light! Light is gathered and analyzed in one of the most critical of all
scientific instruments, the telescope. Use pages 590-596 in the textbook to answer the
questions below.
1. Who first used a telescope to observe the night sky? What year was it?
2. How does light travel through space? What kind of radiation is light? What do we
call the form of light we can see with our eyes? What is a wavelength?
3. Name all the forms of "light" in the electromagnetic spectrum. Where does visible
light lie on the electromagnetic spectrum?
4. What do telescopes do? What is the name of the type of telescope you can look
though with your eye? What does a refracting telescope use to gather and focus light?
What year did Isaac Newton build the first reflecting telescope? What does a reflecting
telescope use to gather and focus light?
5. What is a radio telescope? Why are they so large?
6. Why are observatories often located on mountain tops? What is the problem with the
atmosphere for optical telescopes? What is the problem with city lights for observing?
How do computers help optical telescopes make clearer images?
7. Why types of electromagnetic waves are blocked by Earth's atmosphere? Why are
some telescopes placed in orbit around Earth? Can you name the most famous space
telescope?