Late Microsoft co-founder Paul Allen founded Stratolaunch, a company which successfully tested the largest plane by wingspan on Saturday, April 14th.

It weighs 227 metric tons, has six engines, is 61-metres-long and has a wingspan longer than a football field. It is designed to carry a rocket loaded with a satellite 7,620 metres into the air before shooting the rocket into space.

Stratolaunch says the launching satellites like this is more cost-effective, as planes require less fuel than traditional rockets, cheaper infrastructure and equipment, and they are better equipped to fend off weather delays.

Difficult words: late (no longer alive), fend off (deal with, ignore).