This topic contains a solution. Click here to go to the answer
« previous next »

Author Question: What factors are important when trying to classify a spiral galaxy? a. amount of dust and gas in ... (Read 27 times)

lracut11

  • Hero Member
  • *****
  • Posts: 536
on: Jul 27, 2018
What factors are important when trying to classify a spiral galaxy?
 
  a. amount of dust and gas in the galaxy
  b. structure of the spiral arms
  c. size of the central region
  d. All of the other choices are important.

Question 2

Why are reflection nebulae blue in color?
 
  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

Viet Thy

  • Sr. Member
  • ****
  • Posts: 329
Reply #1 on: Jul 27, 2018
Answer to Question 1

d

Answer to Question 2

Reflection nebulae look blue for the same reason the sky looks blue. Short wavelengths scatter more easily than long wavelengths, so blue photons are scattered. The blue color shows that the dust particles must be very small to preferentially scatter blue photons.


lracut11

  • Member
  • Posts: 536
Reply 2 on: Jul 27, 2018
:D TYSM

sultana.d

  • Member
  • Posts: 320
Reply 3 on: Yesterday
Wow, this really help

« previous next »
 

Did you know?

When blood is deoxygenated and flowing back to the heart through the veins, it is dark reddish-blue in color. Blood in the arteries that is oxygenated and flowing out to the body is bright red. Whereas arterial blood comes out in spurts, venous blood flows.

Did you know?

In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.

Did you know?

Immunoglobulin injections may give short-term protection against, or reduce severity of certain diseases. They help people who have an inherited problem making their own antibodies, or those who are having certain types of cancer treatments.

Did you know?

Human kidneys will clean about 1 million gallons of blood in an average lifetime.

Did you know?

More than 150,000 Americans killed by cardiovascular disease are younger than the age of 65 years.

Interaction web of factors that might influence locust population size. Interaction web of factors that might influence locust population size.
Reprogramming Factors in stem cells Reprogramming Factors in stem cells
Risk factors for suicide. Risk factors for suicide.
Important Concepts in Clinical Massage Therapy Important Concepts in Clinical Massage Therapy
Genes and Risk Factors for Alzheimer Disease Genes and Risk Factors for Alzheimer Disease
Modern-day dust cloud blowing from Africa’s Sahara Modern-day dust cloud blowing from Africa’s Sahara
Video: Fetal Development of the Cardiovascular System

For a complete list of videos, visit our video library