Galactic UFO Thieves

By 2121, aliens will have taken over the world.  You need to use a time machine to go back to 2071 and steal the 4 gears used in the aliens's UFO. Your time machine should only be used for a few small hops if you want to go back to 2121 at the end of your journey.

Use E to use tools, Space to pause/use time travel fuel, and press down on portals to use them.

HINT: Go left first, then go back to the start room and go right.