This topic contains a solution. Click here to go to the answer

Author Question: What is the Hubble constant essentially a measure of? a. the number of galaxies in the universe ... (Read 67 times)

ec501234

  • Hero Member
  • *****
  • Posts: 573
What is the Hubble constant essentially a measure of?
 
  a. the number of galaxies in the universe
  b. the expansion of the universe
  c. the age of the Milky Way galaxy
  d. the amount of dark matter in an average galaxy

Question 2

Why are interstellar absorption lines so narrow compared to the width of lines which originate in the photospheres of stars?
 
  What will be an ideal response?



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

juiceman1987

  • Sr. Member
  • ****
  • Posts: 316
Answer to Question 1

b

Answer to Question 2

Much of the interstellar gas is cold, and its density is very low. Because atoms in the ISM move slowly and collide only rarely, interstellar absorption lines are extremely narrow.




ec501234

  • Member
  • Posts: 573
Reply 2 on: Jul 27, 2018
Excellent


dawsa925

  • Member
  • Posts: 326
Reply 3 on: Yesterday
:D TYSM

 

Did you know?

Though the United States has largely rejected the metric system, it is used for currency, as in 100 pennies = 1 dollar. Previously, the British currency system was used, with measurements such as 12 pence to the shilling, and 20 shillings to the pound.

Did you know?

Amoebae are the simplest type of protozoans, and are characterized by a feeding and dividing trophozoite stage that moves by temporary extensions called pseudopodia or false feet.

Did you know?

Always store hazardous household chemicals in their original containers out of reach of children. These include bleach, paint, strippers and products containing turpentine, garden chemicals, oven cleaners, fondue fuels, nail polish, and nail polish remover.

Did you know?

Blood is approximately twice as thick as water because of the cells and other components found in it.

Did you know?

Although puberty usually occurs in the early teenage years, the world's youngest parents were two Chinese children who had their first baby when they were 8 and 9 years of age.

For a complete list of videos, visit our video library