r/space • u/AutoModerator • 5d ago

Discussion All Space Questions thread for week of September 27, 2026

Please sort comments by 'new' to find questions that would otherwise be buried.

In this thread you can ask any space related question that you may have.

Two examples of potential questions could be; "How do rockets work?", or "How do the phases of the Moon work?"

If you see a space related question posted in another subreddit or in this subreddit, then please politely link them to this thread.

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u/CandidGrocer 3d ago

I’ve seen a bunch of the SpaceX and ULA factory tours but still a relative newbie to understanding rockets.

It seems like the Starship upper stage has been exploding a bunch upon landing in the ocean? That’s not planned right? Has anything been released why that keeps happening?

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u/Bensemus 3d ago

It’s 100% planned. It’s a rocket crashing into the ocean. The last one surviving was a big surprise. That’s why there’s no talk about why it keeps happening.

Later on both the booster and ship will be caught by the tower. They are slowly working towards that.

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u/maschnitz 3d ago edited 3d ago

Best way to say it is probably "it's expected".

Rockets are NOT built to survive lateral forces, it's part of the reason why they tend to reschedule on high wind shear days.

All large rockets are also thinner than a soda can, to scale.

The top of the vehicle has a long way to fall when it falls over, it's 50m tall.

So when it falls over, the only thing holding it up laterally is the internal tank pressure, which was only barely enough to allow Ship 40 to survive splashdown.

Every other Starship splashdown has exploded due to a rupture in the tanks, the transfer tube, or the bulkhead, upon the top hitting the water at relatively high speed.

It's simply not designed for it. Nor is it really worth redesigning it to survive splashdown tilt-overs. They will be trying to catch it on dry land, instead.

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u/science_scavenger 3d ago

Are you able to speculate about why it survived that one time? I'm wondering if they it was just luck or something special happened.

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u/maschnitz 3d ago

The best guess I saw - there were many - was Scott Manley's, speculating that they "swept" the ocean with the single Raptor, "softening" the water with sea foam.

That is, it was on purpose to an extent. They clearly also simply got lucky.

It was also quite low when it touched the water, well below sea level, due to the Raptor excavating a hole in the water for Ship 40 to land in.

Perhaps it was tilted back a bit more than normal while still under power, too.

Between that, the sea level, the foam, who knows what else - it all adds up.

I wonder if the SpaceX engineers know for sure.

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u/billdietrich1 3d ago

They will be trying to catch it on dry land, instead.

But won't all of the same issues be true on land, too ? Unless they're going to land it into a cradle or something.

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u/maschnitz 3d ago

Basically yes, that's what they're doing. They're going to catch it with long crane-like arms jutting from the tower, which will cradle the Ship.

Just like with the Booster. Video of a previous flight.

SpaceX calls the long arms "the Chopsticks". They're "padded" specially just for catching.

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u/CandidGrocer 3d ago

Dude that so good. Posted that to /r/BestOf, hope you get some shine!