The NASA/ESA Ulysses spacecraft's power is starting to run down, and soon it won't have enough to keep itself warm. When the spacecraft was first launched in 1990 to study the Sun, its reactor produced 285 watts of power, but now almost 14 years later, it's down to 207 watts. If it gets too much lower, the spacecraft won't be able to operate the heaters that keep the fuel flowing. Without this fuel, it won't be able to orient its main antenna towards the Earth to transfer data.