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

Author Question: Explain how observations of white-dwarf supernovae provide information on the expansion of the ... (Read 165 times)

cagreen833

  • Hero Member
  • *****
  • Posts: 544
Explain how observations of white-dwarf supernovae provide information on the expansion of the universe when it was younger.
 
  What will be an ideal response?

Question 2

A black hole may be visible because electromagnetic radiation is emitted from an ________ surrounding it, heated up enough to emit X-rays.
 
  Fill in the blank(s) with correct word



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

hanadaa

  • Sr. Member
  • ****
  • Posts: 339
Answer to Question 1

White-dwarf supernovae attain the same maximum brightness and are therefore good standard candles with which to measure galaxy distances. Therefore, if we see a white-dwarf supernova in a distant galaxy we can measure how far away it is, and thus how old the universe was when the supernova exploded. We can also measure the Doppler shift of spectral lines in the galaxy and find how fast it is moving away from us. This tells us how fast the universe was expanding when it was much younger.

Answer to Question 2

accretion disk




cagreen833

  • Member
  • Posts: 544
Reply 2 on: Jul 27, 2018
YES! Correct, THANKS for helping me on my review


mcabuhat

  • Member
  • Posts: 344
Reply 3 on: Yesterday
Thanks for the timely response, appreciate it

 

Did you know?

The effects of organophosphate poisoning are referred to by using the abbreviations “SLUD” or “SLUDGE,” It stands for: salivation, lacrimation, urination, defecation, GI upset, and emesis.

Did you know?

Elderly adults are living longer, and causes of death are shifting. At the same time, autopsy rates are at or near their lowest in history.

Did you know?

The human body's pharmacokinetics are quite varied. Our hair holds onto drugs longer than our urine, blood, or saliva. For example, alcohol can be detected in the hair for up to 90 days after it was consumed. The same is true for marijuana, cocaine, ecstasy, heroin, methamphetamine, and nicotine.

Did you know?

The first war in which wide-scale use of anesthetics occurred was the Civil War, and 80% of all wounds were in the extremities.

Did you know?

Elderly adults are at greatest risk of stroke and myocardial infarction and have the most to gain from prophylaxis. Patients ages 60 to 80 years with blood pressures above 160/90 mm Hg should benefit from antihypertensive treatment.

For a complete list of videos, visit our video library