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

Author Question: What is proper motion? A) It is the true, not apparent, motion of a star in space. B) It is the ... (Read 57 times)

bcretired

  • Hero Member
  • *****
  • Posts: 525
What is proper motion?
 
  A) It is the true, not apparent, motion of a star in space.
  B) It is the apparent shift as we go to opposite sides of our orbit every six months.
  C) It is the annual apparent motion of a star across the sky.
  D) It is the motion of a star towards or away from us, revealed by Doppler shifts.
  E) It is the orbital motion of a star around the Galaxy.

Question 2

How does Drake define a technological civilization?
 
  A) one that can get into space
  B) one that can communicate over interstellar distances
  C) one that has a written language
  D) one that can construct metal tools
  E) one that can have the intelligence not to destroy itself



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

lou

  • Sr. Member
  • ****
  • Posts: 286
Answer to Question 1

C

Answer to Question 2

B




bcretired

  • Member
  • Posts: 525
Reply 2 on: Jul 27, 2018
Wow, this really help


Bigfoot1984

  • Member
  • Posts: 321
Reply 3 on: Yesterday
Excellent

 

Did you know?

According to the National Institute of Environmental Health Sciences, lung disease is the third leading killer in the United States, responsible for one in seven deaths. It is the leading cause of death among infants under the age of one year.

Did you know?

Fungal nail infections account for up to 30% of all skin infections. They affect 5% of the general population—mostly people over the age of 70.

Did you know?

Congestive heart failure is a serious disorder that carries a reduced life expectancy. Heart failure is usually a chronic illness, and it may worsen with infection or other physical stressors.

Did you know?

Complications of influenza include: bacterial pneumonia, ear and sinus infections, dehydration, and worsening of chronic conditions such as asthma, congestive heart failure, or diabetes.

Did you know?

More than 20 million Americans cite use of marijuana within the past 30 days, according to the National Survey on Drug Use and Health (NSDUH). More than 8 million admit to using it almost every day.

For a complete list of videos, visit our video library