un- – – – – tethered

From Astronomy Pic of the Day:

Explanation: At about 100 meters from the cargo bay of the space shuttle Challenger, Bruce McCandless II was further out than anyone had ever been before. Guided by a Manned Maneuvering Unit (MMU), astronaut McCandless, pictured above, was floating free in space. McCandless and fellow NASA astronaut Robert Stewart were the first to experience such an "untethered space walk" during Space Shuttle mission 41-B in 1984. The MMU works by shooting jets of nitrogen and has since been 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 replaced with the SAFER backpack propulsion unit.



About Fr. John Zuhlsdorf

Fr. Z is the guy who runs this blog. o{]:¬)
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  1. I think I’d rather wait until after the General Resurrection before I try a stunt like that.

  2. AndyMo says:

    I’m with Anita. That guy’s gotta be the bravest person ever.

  3. Mark R says:

    Can you hear me, Major Tom?

  4. HAL, don’t forget to let me back in…

  5. 4mercy says:

    All my son could say was, “WOW!” I have to agree!

  6. Fr. John Mary says:

    I want to make a public oommendantion of my cousin, Scott Altman, who was the Commander of the

  7. Fr. John Mary says:

    Sorry…hit the wrong button.
    Anyway, my cousin, Scott Altman, was the Commander of the last Space Shuttle in May. He is a brave and brilliant man. May God continue to bless him always.

  8. Athelstan says:

    Alas, the MMU has not been used since the Challenger disaster, mainly out of safety concerns. Spacewalks are all currently done tethered.

    More trivia: McCandless was CAPCOM for Apollo II. He hasn’t led a boring life.

  9. Gabriella says:

    Looking at God’s creation from up there!
    A spontaneous prayer must have certainly burst out of his heart …

  10. chironomo says:

    Indeed brave… given the unpredictability of equipment. If that thing breaks down you’re in a pretty much hopeless situation I would imagine… unless of course someone else on board has one.

  11. Tina in Ashburn says:


    I guess he has no fear of heights?

  12. irishgirl says:

    Whoa-how cool is that?

    Can you imagine just floating around in space, looking down on God’s creation on earth, and seeing His magnificience in the heavens above?

    ‘The heavens are telling the glory of God…’ [I’m thinking of Haydn’s ‘The Creation’ ]

  13. Chris M says:

    If I were that far from my craft.. well.. let’s just say my spacesuit just became a wetsuit!

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