Teacher's Answer Key

4. There is an event that occurs in space known as a Solar Proton Event (SPE). SPEs are the most dangerous to astronauts because of our inability to predict them. They occur about once every month during solar maximum, and once every eight months during solar minimum. Typical radiation dosages are about 0.4 rems inside a spacecraft or similar shelter. The amount of rems varies due to the intensity of the SPE. During your trip, assume that you will encounter 3 SPEs on your way to Mars, 10 SPEs while on Mars, and I SPE on your trip home. To simulate the random amount of rems received from SPES, toss a dice and using the chart below, the number on the dice equals the corresponding dosage. Example, a rofl of 5 gives you a dosage of 2.0 rems. Repeat for each SPE and add the amount of the total SPE rems for each part of the trip. Here is a sample result of the dice tossing outcomes:

DiceDose
10.1
20.3
30.4
40.8
52.0
610.0

Trip to Mars:

SPEDose
10.4
22.0
30.1

Total rems = 2.5

On Mars:

SPEDose
10.3
22.0
30.4
40.3
510.0
60.4
70.1
82.0
90.3
100.3

Total rems = 16.1

Trip to Earth:

SPEDose
10.8

Total rems = 0.8

7. Calculate the mission's total dose by filling in the numbers below:
Amount of rems on trip to Mars + total SPE on trip to Mars = 15.4 + 2.5 = 17.9
Amount of rems while on Mars + Total SPE while on Mars = 43.8 + 16.1 = 59.9
Amount of rems on trip to Earth + Total SPE on trip to Earth = 38.4 + 0.8 = 39.2
Total dosage for entire trip = 117.0 rems