The Avengers: Endgame trailer has been out for over a week now and it features Robert Downey Jr.'s Tony Stark lost in space. Worried Marvel Cinematic Universe fans started messaging NASA in order to make a plan to bring the fictional character back to Earth safely to join the rest of the Avengers to help take out Thanos. NASA responded and gave Marvel Studios some advice about bringing Stark home and now Robert Downey Jr. is responding to their plan.

NASA says that Marvel Studios should have all their "ground teams" use "all resources" to scan the skies in an effort to locate Tony Stark, which the studio appreciated, sending a tweet in return. Now, Robert Downey Jr. has caught wind of the situation and also appreciates the friendly advice that NASA had to offer. He says, "Always good to know NASA has your back," which also prompted another response from NASA, noting that, "Failure is not an option."

Obviously, this is all in good fun, but it's pretty amazing that NASA responded to the MCU devotees in the first place. It just goes to show how big the Avengers are around the world. The hype for Avengers: Endgame is off the charts and hardcore fans are already asking when the second trailer is going to drop after only having the first one for a week. It looks like you can count some NASA employees in that boat as well, adding to the collective excitement of the sequel's release early next year.

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The Avengers: Endgame trailer make things look pretty grim for Tony Stark as he drifts through space after battling Thanos on Titan. He and Nebula are on the Benatar without any food or water, which prompts Stark to try and send a goodbye message to Pepper Potts using his busted up Iron Man mask. While things definitely don't look good for the character, fans have started sharing theories about how Stark and Nebula will be rescued. Pepper Potts suiting up as Rescue has been thrown around, but the dominating theory at this time is that Captain Marvel is going to save the day. However, that is all just speculation at this point in time, which has not been officially confirmed by anybody.

Avengers: Endgame is a big mystery at this point, even after the trailer release last week. In fact, there's probably even more questions now that the trailer is finally out there. Some MCU fans may feel disappointed that there's so much mystery surrounding the sequel, but it has created some pretty amazing fan theories that have been shared on social media over the last few months, creating a new network of detective fans who share everything that they have. Thankfully, the wait isn't too much longer after Marvel Studios moved the release date of Avengers: Endgame to the end of April. You can check out the NASA exchange below, thanks to Robert Downey Jr.'s Twitter account.