The Galileo space probe was launched on its long journey past Venus and Earth
in \(1989,\) with an ultimate goal of Jupiter. Its power source is \(11.0
\mathrm{kg}\) of \(^{238} \mathrm{Pu}\) a by-product of nuclear weapons plutonium
production. Electrical energy is generated thermoelectrically from the heat
produced when the \(5.59-\mathrm{MeV} \quad \alpha\) particles emitted in each
decay crash to a halt inside the plutonium and its shielding. The half-life of
\(^{238} \mathrm{Pu}\) is 87.7 years.
(a) What was the original activity of the \(^{238} \mathrm{Pu}\) in becquerels?
(b) What power was emitted in kilowatts?
(c) What power was emitted 12.0 y after launch? You may neglect any extra
energy from daughter nuclides and any losses from escaping \(\gamma\) rays.