| 01. | Find the density (in atoms per cubic centimeter) of a Bok globule having a radius of 1 light-year and a mass of 100 M⊙. (Assume that the globule is made purely of hydrogen atoms.) For your comparison, the density of a typical H II region is between 80 and 600 atoms per cm3. |
| 02. | At one stage during its birth, the protosun had a luminosity of 1000 L⊙ and a surface temperature of about 1000 K. At this time, what was its radius? Express your answer in three ways: as a multiple of the Sun's present-day radius, in kilometers, and in astronomical units. |
| 03. | The concentration, or abundance, of ethyl alcohol in a typical molecular cloud is about 1 molecule per 108 cubic meters. What volume of such a cloud would contain enough alcohol to make a martini (about 10 grams of alcohol)? A molecule of ethyl alcohol has 46 times the mass of a hydrogen atoms (that is, ethyl alcohol has a molecular weight of 46). |