Astronomy Picture of the Day - To Fly Free in Space

NASA ^ | 15 Feb, 2026 | Image Credit: NASA, STS-41B

[MtnClimber]

Explanation: What would it be like to fly free in space? About 100 meters from the cargo bay of a space shuttle, Bruce McCandless II was living the dream -- floating farther out than anyone had ever been before. Guided by a Manned Maneuvering Unit (MMU), astronaut McCandless, pictured, was floating free in space. During Space Shuttle mission 41-B in 1984, McCandless and fellow NASA astronaut Robert Stewart were the first to experience such an "untethered space walk". The MMU worked by shooting jets of nitrogen and was used to help deploy and retrieve satellites. With a mass over 140 kilograms, an MMU is heavy on Earth, but, like everything, is weightless when drifting in orbit. The MMU was later replaced with the SAFER backpack propulsion unit.

[MtnClimber]

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[MtnClimber]

[MtnClimber]

Pinging the APOD list

🪐 🌟 🌌 🍔

[Jamestown1630]

That is terrifying to think about...

[Retain Mike]

Good point. How does he ever get back?

[Repeal The 17th]

How does he ever get back?
-
He uses a fire extinguisher like Matt Damon did
in the movie “the Martian”.

[TigersEye]

I'm sorry, Dave. I took the liberty of emptying the nitrogen from your MMU.
It was for the good of the mission, Dave.

[Pete from Shawnee Mission]

Untethered and floating free...you do not have much room for error.

[Jamestown1630]

Jets of nitrogen, it says; a sort of jet pack.

More nerve than I could ever muster...

[Pete from Shawnee Mission]

Thanks for posting!

[telescope115]

It had to be an amazing experience.

[doorgunner69]

I would still have a spool of monofilament line attached.

Cameras would not see it in the glare.

[AFB-XYZ]

Agreed.

“In space, no one can hear you scream”. (Alien, I think?)

[OldMissileer]

McCandless helped design the MMU.

[DannyTN]

I don’t want to fly in space even if it is free.

That’s a waste of a perfectly good earth.

[maddog55]

That would take some big balls..... an awesome photo!!

[Puppage]

Balls of steel.

[Moltke]

Red Bull would do a stunt where he goes in the opposite direction of the space station...”I’ll do one lap and meet you back here in a few hours!”

[Vaduz]

They pick him up on the next orbit unless he sees the finger.