Question 1

4 pts

As mentioned above in the general intro, NASA would use a high-gain directional dish to

collimate radio-wave photons into a beam (though by the time that beam gets to Saturn, it has

spread out to an area of about 9 Saturn diameters).

Real Problem Starts Here

Imagine you were instead trying to talk to Cassini through an high-powered FM radio

antenna with a power output of 60 kW and a frequency of 94,9 MHz. Assume your

transmitter radiates its signal equally in all directions. How many photons will be intercepted

per second by the spacecraft antenna dish (12.5 m² area) if the spacecraft is 1,683 million

kilometers away?

Note: required precision is 1%.

Sanity check: the answer should be in the range of 2e5 to 1.1e6