You are on an interstellar mission from the Earth to the 8.7light-years distant star Sirius. Your spaceship can travel with 70%the speed of light and has a cylindrical shape with a diameter of 6m at the front surface and a length of 25 m. You have to cross theinterstellar medium with an approximated density of 1 hydrogenatom/m3 . (a) Calculate the time it takes your spaceship to reachSirius. (b) Determine the mass of interstellar gas that collideswith your spaceship during the mission. Note: Use 1.673 × 10^−27 kgas proton mass.
Because you are moving with an enormous speed, your mission fromthe previous problem A.1 will be influenced by the eects of timedilation described by special relativity: Your spaceship launchesin June 2020 and returns back to Earth directly aer arriving atSirius. (a) How many years will have passed from your perspective?(b) At which Earth date (year and month) will you arrive back toEarth?
