Whether in the real world, depicted in cartoons, or in a hobbyist's back yard, rockets always seem to have fins. Or if not fins, at least some other kind of protrusions along the outside — they ...

Here’s why SpaceX really needed to change out that part on Starship Grid fins have been essential to the landing of 230 rockets.

The pan, produced by FireUp, features fins around its outside inspired by heat transfer methods used in jet engines and rockets.

A photo of SpaceX's new titanium grid fins. Credit: SpaceX The Falcon 9 rocket's first stage being used for Sunday's mission is a good candidate for future reuse.

The launch of a Long March 2C from Xichang last week included a first use of grid fins by China to minimize the threat posed by the spent first stage to populated areas downrange.