Look at the Jupiter Moon Tracker Results diagram below and confirm that you understand it by using the blank diagram on the page after the tracker to draw an orbit like Titania's. (Same orbital distance as Io, 8.7 day period). Making the Calculation: Mass of Jupiter from the orbits of its moons You will use the Jupiter Moon Tracker Results and the Calculation Table to complete the calculation. ? Write down the Period (in days) and Amplitude (size of orbit in Jupiter radii) in Columns 2 & 4 of the Calculation Table. ? Convert the period to years and the amplitude/size of orbit to AU to get Columns 3 & 5. Recall that 1 year = 365.24 days. 1 AU = 2100 Jupiter radii. (Think: Should the number of years be more or less than the number of days? Should the number of AU be more or less than the number of Jupiter radii?) ? Use Columns 3 & 5 to calculate Columns 6 as indicated in the table on the next page. (Note that your textbook's equation for Newton's version of Kepler's third law looks more complicated because of the units it uses. Working in years, AUs and solar masses we can keep it simpler.) ? Column 6 gives the mass of Jupiter as a fraction of the mass of the Sun. Convert this to kilograms for Column 7. Recall that the mass of the Sun is 2 X 1030 kg.

Tracking the Moons of Jupiter