Alien Planet starts out with an interstellar spacecraft named Von Braun , leaving Earth's orbit .  Traveling at 20 % the speed of light , it reaches Darwin IV in 42 years .  Upon reaching orbit , it deploys the Darwin Reconnaissance Orbiter , Which looks for potential landing sites for the probes .  The first probe , Balboa , explodes along with its lifting body transport during entry , because one of its wings failed to unfold .  Two backup probes , Leonardo da Vinci and Isaac Newton , successfully land on the planet , and learn much about its bizarre indigenous lifeforms , including an apparently sapient species .  The robotic probes sent out to research on Darwin IV are called Horus Probes .  Each Horus probe consists of an { { convert } } long inflatable , hydrogen-filled balloon , Which is covered with solar receptors , a computer ` brain ' , a ` head ' covered with sensors , and several smaller robots that can be sent to places too dangerous for the probes themselves .  The probes have a limited degree of artificial intelligence , very similar to the ` processing power ' of a 4-year-old .  All the real thinking is done by a supercomputer in the orbiting Von Braun .  The probes are programmed with different personalities ; Ike is more cautious , while Leo is the risk-taker .  The two probes are also equipped with a holographic message that will be projected to any sentient life found on Darwin .  After the two probes inflate their gas-bags , they encounter a voracious Arrowtongue and watch it pursue a Gyrosprinter . 
What forms of artificial intelligence is used on the spacecraft?
Two different personalities: cautious Ike and Risk-taker Leo