« previous next »

Author Question: Using the technique of main-sequence fitting to determine the distance to a star cluster requires ... (Read 28 times)

Capo

  • Hero Member
  • *****
  • Posts: 545
on: Jul 27, 2018
Using the technique of main-sequence fitting to determine the distance to a star cluster requires that ________.
 
  A) we use ultraviolet and X-ray telescopes
  B) we have telescopes powerful enough to allow us to identify the spectral types of main-sequence stars of many masses in the cluster
  C) the cluster be near enough for us to measure the parallax of its stars
  D) we have a well-calibrated period-luminosity relation for Cepheid variable stars

Question 2

The COBE data allow us to test the isotropy of the universe.
 
  Indicate whether the statement is true or false


yuyiding

  • Sr. Member
  • ****
  • Posts: 357
Reply #1 on: Jul 27, 2018
Answer to Question 1

B

Answer to Question 2

TRUE


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
« previous next »
 

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?

Parkinson's disease is both chronic and progressive. This means that it persists over a long period of time and that its symptoms grow worse over time.

Did you know?

To maintain good kidney function, you should drink at least 3 quarts of water daily. Water dilutes urine and helps prevent concentrations of salts and minerals that can lead to kidney stone formation. Chronic dehydration is a major contributor to the development of kidney stones.

Did you know?

Throughout history, plants containing cardiac steroids have been used as heart drugs and as poisons (e.g., in arrows used in combat), emetics, and diuretics.

Did you know?

Excessive alcohol use costs the country approximately $235 billion every year.

Examples of cell-to-cell communication based on the distance between cells Examples of cell-to-cell communication based on the distance between cells
In Chuck Close's portrait, the face is quite recognizable when viewed from a distance. Close ... In Chuck Close's portrait, the face is quite recognizable when viewed from a distance. Close ...
Redrape the back, face the head of the table, and apply passive touch as finishing technique. Gently ... Redrape the back, face the head of the table, and apply passive touch as finishing technique. Gently ...
A palindromic DNA Sequence A palindromic DNA Sequence
Transillumination of the maxillary sinuses using alternate technique Transillumination of the maxillary sinuses using alternate technique
Gel electrophoresis, an essential laboratory technique in biological science research Gel electrophoresis, an essential laboratory technique in biological science research
Video: Fetal Development of the Cardiovascular System

For a complete list of videos, visit our video library