2. The diameter of the sun's visible surface is about

86,400 miles.
86,400 kilometers.
864,000 miles.
8,630,000 miles.

3. A very important instrument used for studying the sun is a

spectrograph which displays a set of spectral lines.
spectrograph which creates a three dimensional image.
green filter which creates a three dimensional image.
green filter which creates a set of spectral lines.

4. The presence of magnetic fields on the sun is demonstrated by the

Zebra Effect.
splitting of some spectral lines.
broadening of some spectral lines.
temperature of the regions of magnetism.

5. Certain types of radiations or wavelengths of energy given off by the sun can only be studied by

tomographic instruments.
helioseismic instruments.
sending instruments above the Earth's atmosphere.
CCD's (charged coupled devices).

6. The solar wind (see Helps & Hints)

blows around the sun.
consists of particles that escape from the sun's hot corona.
blows more strongly during fall and winter.
blows more strongly during fall and summer.

7. The sun consists mainly of hydrogen and

nitrogen.
carbon.
iron.
helium.

8. If the photosphere is considered the surface of the sun, layers or regions of the interior in order are (from the center out) (See p. 171-173 text)

core - radiative zone - convective zone.
core - convective zone - radiative zone.
chromosphere - core - convective zone - radiative zone.
core - chromosphere - radiative zone - convective zone.

9. The photosphere is

less dense and cooler than the chromosphere.
less dense and hotter than the chromosphere.
the bright disk that we see with our naked eye.
more dense and hotter than the corona.

10. Sunspots are probably created by

flares and prominences.
flares and coronal holes.
magnetic fields that are thousands of times stronger than the Earth's magnetic field.
magnetic fields that are hundreds of times stronger than the Earth's magnetic field.

11. Choose the incorrect statement concerning sunspots.

Sunspots are associated with flares and magnetic fields.
Sunspots seem to move due to the rotation of the Earth around the sun.
Sunspots change shape and increase and decrease in number.
Sunspots can be partially explained by the Babcock Model.

12. Choose the incorrect statement concerning strong displays of magnetic activity on the sun. (see Helps & Hints)

Such displays can cause auroras and other disturbances to our magnetic field.
Such displays can cause changes in the shape and size of the solar corona.
Such displays can cause power outages and interfere with radio communication on Earth.
Such displays can occur most frequently every four years.

13. Which of the following is true concerning the sun? (see Helps & Hints)

auroras and flares are less frequent during sunspot minimum.
auroras and flares are less frequent during sunspot maximum.
auroras and flares are more frequent during sunspot minimum.
auroras are more frequent but flares less frequent during sunspot maximum.

14. A sunspot cycle, as measured from one sunspot minimum to the next, lasts about

4 years.
11 years.
22 years.
70 years.

15. The Little Ice Age, or Maunder minimum, that occurred from 1645 to 1715, coincided with a

lot of solar flare activity.
lot of aurora.
strong solar wind.
lack of sunspots.

Lesson 8 "Stellar Properties"

16. The branch of astronomy that measures the positions of stars, the sun or planets is known as

astrogeometry.
metriastronomy.
stellarometry.
astrometry.

17. When measurements are made on a nearby star from different positions in the Earth's orbit, slight variations in its position can be observed. This phenomena is known as

retrograde motion.
parallax.
angular stellarometry.
stellar astrometry.

18. Choose the incorrect statement concerning the parallax of objects.

Early astronomers could not see parallax for stars even though they tried.
The parallax of stars is measured in arc seconds.
The parallax of stars is measured in parsecs
The European satellite, Hipparcos, measured the parallax of thousands of stars.

19. A fourth (4th) magnitude star is about (see Help & Hints)

2.5 times fainter than a fifth (5th) magnitude star.
100 times fainter than a fifth (5th) magnitude star.
100 times brighter than a fifth (5th) magnitude star.
2.5 times fainter than a third (3d) magnitude star.

20. Moving three times farther away from a star would mean that the star would appear to be

3 times fainter.
9 times fainter.
2.5 times fainter.
100 times fainter.

21. The true brightness of stars, called luminosity, ranges from (as stated on the video)

100,000 times brighter than the sun to less than 10,000 times fainter than the sun.
100,000 times brighter than the sun to 100,000 times fainter than the sun.
one million times brighter than the sun to one million times fainter than the sun.
one million times brighter than the sun to about 10,000 times fainter than the sun.

22. The surface temperature of main sequence stars range from

a few thousand degrees to a few ten thousand degrees (1000's of degrees-10,000's of degrees).
a few thousand degrees to a few hundred thousand degrees (1000's of degrees-100,000s' of degrees).
a few tens of thousands of degrees to a few hundred thousand degrees (10,000's of degrees-100,000's of degrees).
a few tens of thousands of degrees to a few million degrees (10,000's of degrees-1,000,000's of degrees).

23. The Hertzsprung-Russell Diagram clearly shows the relationship between

temperature and distance.
temperature(spectral class) and magnitude.
temperature and mass.
luminosity and distance.

24. A study of eclipsing binary stars help astronomers primarily determine their

apparent magnitude and luminosity.
apparent magnitude and mass.
luminosity and mass.
mass and diameter.

25. Briefly stated, the Mass-Luminosity Relationship for main sequence stars says that

lower luminosity stars have lower apparent magnitudes.
lower luminosity stars have greater apparent magnitudes.
higher luminosity stars have lower masses.
lower luminosity stars have lower masses.

Prepared by: Mike Mitchell

Be sure to do the questions (A-I) on the Hertzsprung-Russell Diagram #8 on Helps & Hints for Quiz 3, Lesson 8.