What causes stars to twinkle?
A) It is intrinsic to the starstheir brightness varies as they expand and contract.
B) variations in the absorption of the atmosphere
C) variable absorption by interstellar gas along the line of sight to the star
D) bending of light rays by turbulent layers in the atmosphere
E) the inability of the human eye to see faint objects
Question 2
The red hydrogen alpha line carries more energy per photon than the blue-green hydrogen beta line does.
Indicate whether the statement is true or false
Plotting the Ages of Stars
Evolution of Stars Off the Main Sequence
Both the top and bottom pattern have the same frequency. However, the amount of on-time varies.
Extrinsic and intrinsic signaling pathways leading to apoptosis
Evolutionary Stages of Stars
Intrinsic termination