Author Question: The identification of spiral nebulae as large groupings of stars outside of our own galaxy was ... (Read 74 times)

jeatrice

  • Hero Member
  • *****
  • Posts: 543
The identification of spiral nebulae as large groupings of stars outside of our own galaxy was proven by ____.
 
  a. photographic plates made by Edwin Hubble showing stars and Cepheid variables
  b. the results of the Shapley-Curtis debate
 c. Immanual Kant's island universe theory
 d. William Parsons' observation and description of their spiral structure
 e. Harlow Shapley's observations of their radio spectrum

Question 2

What does a refracting telescope use to gather and focus light?
 
  a. eyepiece
 b. mirror
 c. lens
 d. photometer
 e. active optics



lorealeza77

  • Sr. Member
  • ****
  • Posts: 356
Answer to Question 1

a

Answer to Question 2

c



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

The use of salicylates dates back 2,500 years to Hippocrates’s recommendation of willow bark (from which a salicylate is derived) as an aid to the pains of childbirth. However, overdosage of salicylates can harm body fluids, electrolytes, the CNS, the GI tract, the ears, the lungs, the blood, the liver, and the kidneys and cause coma or death.

Did you know?

The calories found in one piece of cherry cheesecake could light a 60-watt light bulb for 1.5 hours.

Did you know?

Colchicine is a highly poisonous alkaloid originally extracted from a type of saffron plant that is used mainly to treat gout.

Did you know?

The top 10 most important tips that will help you grow old gracefully include (1) quit smoking, (2) keep your weight down, (3) take supplements, (4) skip a meal each day or fast 1 day per week, (5) get a pet, (6) get medical help for chronic pain, (7) walk regularly, (8) reduce arguments, (9) put live plants in your living space, and (10) do some weight training.

Did you know?

Signs of depression include feeling sad most of the time for 2 weeks or longer; loss of interest in things normally enjoyed; lack of energy; sleep and appetite disturbances; weight changes; feelings of hopelessness, helplessness, or worthlessness; an inability to make decisions; and thoughts of death and suicide.

For a complete list of videos, visit our video library