There, it will undergo preparations for a two-day, 12-mile trip on Oct. 12 and 13 via surface streets to the California Science Center.  The shuttle will travel north from the airport east on Manchester, north on Crenshaw and then east again on Martin Luther King.  In order to make way for the shuttle — which is five stories high and 78 feet wide — crews will have to cut down nearly 400 trees.  The science center has agreed to plant 1,000 new trees to replace those scheduled for removal. Workers will also raise overhead utility wires and temporarily take down hundreds of utility poles, street lights and traffic signals. The shuttle will be on display at the science center starting on Oct. 30. Endeavour replaced Challenger, which exploded in 1986, killing seven astronauts. Its name was chosen by schoolchildren after a ship built to cross the South Pacific in the 1700s. Endeavour went on to fly 25 missions, including 12 to help construct and outfit the space station, and logged nearly 123 million miles in flight during 4,671 orbits.