more exam two questions

Question 1

What produces a type-I supernova?

Answer 1

mass transfer onto a white dwarf pushing it over 1.4 solar masses

Question 2

Iron, and elements heavier than iron, were produced in

Answer 2

supernovae

Question 3

The supernova that formed M-1, the Crab Nebula, was observed in:

Answer 3

1054 AD by Chinese and Middle Eastern astronomers.

Question 4

In the Lighthouse Model

Answer 4

if the beam sweeps across us, we will detect a pulse of radiation.

Question 5

For a white dwarf to explode entirely as a Type I supernova, its mass must be:

Answer 5

1.4 solar masses, the Chandrasekhar Limit.

Question 6

A star can be a supernova

Answer 6

only once

Question 7

A white dwarf

Answer 7

all of the other answers are correct.

Question 8

Just as a low-mass main sequence star runs out of fuel in its core, it actually becomes brighter. How is this possible?

Answer 8

The core contracts, raising the temperature and increasing the size of the region of hydrogen shell-burning.

Question 9

What is the most important requirement for a star with a main sequence mass of 5 solar masses to become a white dwarf?

Answer 9

It must lose at least 3.6 solar masses first.

Question 10

At which stage in a Sun-like star’s life is its core the least dense?

Answer 10

Main Sequence

Question 11

Which of the following persons reorganized the spectral classification scheme into the one we use today and personally classified over 400,000 stars

Answer 11

Annie Jump Cannon