Astronomy college course/Introduction to stellar measurements/questions/Original version of this quiz

Questions based on Introduction to Stellar Measurements

1 Stellar parallax is

	an annual change in angular position of a star as seen from Earth
	an astronomical object with known luminosity.
	the total amount of energy emitted per unit time.
	a numerical measure of brightness as seen from Earth
	a numerical measure of brightness as seen from a distance of approximately 33 light-years

2 Luminosity is

	an annual change in angular position of a star as seen from Earth
	an astronomical object with known luminosity.
	the total amount of energy emitted per unit time.
	a numerical measure of brightness as seen from Earth
	a numerical measure of brightness as seen from a distance of approximately 33 light-years

3 A standard candle is

	an annual change in angular position of a star as seen from Earth
	an astronomical object with known luminosity.
	the total amount of energy emitted per unit time.
	a numerical measure of brightness as seen from Earth
	a numerical measure of brightness as seen from a distance of approximately 33 light-years

4 Absolute magnitude is

	an annual change in angular position of a star as seen from Earth
	an astronomical object with known luminosity.
	the total amount of energy emitted per unit time.
	a numerical measure of brightness as seen from Earth
	a numerical measure of brightness as seen from a distance of approximately 33 light-years

5 Relative magnitude is

	an annual change in angular position of a star as seen from Earth
	an astronomical object with known luminosity.
	the total amount of energy emitted per unit time.
	a numerical measure of brightness as seen from Earth
	a numerical measure of brightness as seen from a distance of approximately 33 light-years

6 In 1989 the satellite Hipparcos was launched primarily for obtaining parallaxes and proper motions allowing measurements of stellar parallax for stars up to about 500 parsecs away, which is about ____ times the diameter of the Milky Way Galaxy.

	.015
	0.15
	1.5
	15
	150

7 An object emits thermal (blackbody) radiation with a peak wavelength of 250nm. How does its temperature compare with the Sun?

	The temperature is the same
	2 times colder than the Sun
	2 times hotter than the Sun
	5 times colder than the Sun
	5 times hotter than the Sun

8 The "normalized intensity" of a Sun-like star situated one parsec from Earth would be 4πI = 1. What is 4πI for a star with 100 times the Sun's energy output that is situated 10pc from Earth?

	10-2
	10-3
	10-1
	10-4
	1

9 An orbiting satellite makes a circular orbit 5 AU from the Sun. It measures a parallax angle of 0.2 of an arcsecond (each way from the average position). What is the star's distance?

	10 parsecs
	25 parsecs
	5 parsecs
	1 parsec
	50 parsecs

10 A star that is increasing it's temperature while maintaining constant luminosity is

	getting smaller in size
	turning red
	in the process of dying
	on the verge of becoming a supernovae
	e) getting larger in size

11 The range of wavelength for visible light is between

	400 and 700 nanometers
	1 and 10 nanometers
	600 and 1200 nanometers
	0.1 and 10 nanometers
	5000 and 6000 nanometers

12 Based on the HR diagrams and images in stars shown in the materials, a very large red supergiant has a diameter that is about ____ greater than a small white dwarf.

	3x103
	3x109
	3x1011
	3x107
	3x105