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Per Elon's tweet those grid fins were much better behaved than previous versions. Nothing got hot enough to start showing up in the visible spectrum (good). And what was interesting for me was the lack of gunk landing on the camera. (presumably from the fact that the covering of the fins wasn't burning off like it had in previous flights). What is particularly impressive for me is the slow and steady progress on the 'landed' F9's. The first one successfully landed looked really beat up, and the next couple marginally less so, Friday's went through a part of flight regime that SpaceX had deemed "un-recoverable" and an this one came through looking quite good. Still feels like science fiction to me ...

> Nothing got hot enough to start showing up in the visible spectrum (good).

The new grid fins undergo the same amount of heating, they're just better able to cope with the heat. The reduced heat in this case was due to the much lower energy entry profile (the partial boostback burn killed a large chunk of the stage's velocity prior to reentry, combined with the fact that it was a lower energy orbit in the first place).

Thanks Josh. I went back and reviewed the Iridium 1 footage and saw that even the Aluminum fins had no trouble with this particular launch and recovery option. I am looking forward to seeing the first GTO launch with a booster that has them.

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