Multiple Choice
You discover a binary star system in which one member is a15 solar mass main- sequence star and the other star is a 10 solar mass giant star. How do we believe that a star system such as this might have come to exist?
A) Although both stars probably formed from the same clump of gas, the more massive one must have had its birth slowed so that it became a main- sequence star millions of years later than its less massive companion.
B) The main- sequence star probably is a pulsating variable star and therefore appears to be less massive than it really is.
C) The two stars probably were once separate but became a binary when a close encounter allowed their mutual gravity to pull them together.
D) Other than the very low odds of finding a system with two such massive stars, there is nothing surprising about the fact that such systems exist.
E) The giant must once have been the more massive star but transferred some of its mass to its companion.
Correct Answer:

Verified
Correct Answer:
Verified
Q66: What is a planetary nebula?<br>A)gas created from
Q67: Which part of the electromagnetic spectrum generally
Q68: What happens when the gravity of a
Q69: Which type of star spends the longest
Q70: We do not know for certain whether
Q72: When does a protostar become a main-
Q73: Which of the following properties describes a
Q74: Historical Supernova: You find an ancient Chinese
Q75: A spinning neutron star has been observed
Q76: After a supernova explosion, the remains of