Astronomy Picture of the Day -- To Fly Free in Space

NASA ^ | January 01, 2012 | (see photo credit)

[SunkenCiv]

Explanation: At about 100 meters from the cargo bay of the space shuttle Challenger, Bruce McCandless II was farther 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.

[SunkenCiv]

[Credit: STS-41B, NASA]

[SunkenCiv]

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[annieokie]

WOW!!! what courage, scares me to just look at that. Beautiful picture, thanks.

[onyx]

AWESOME!

[BenLurkin]

Oh man no way.

[flaglady47]

Geez, my acrophobia quotient just jumped to maxed out. Great pic though.

[onyx]

At first glance, I thought and hoped it was a toy!

[MaxMax]

Ha Ha very funny, ok guys this isn't funny anymore!

[dr_lew]

With a mass over 140 kilograms, an MMU is heavy on Earth, but, like everything, is weightless when drifting in orbit.

"Weightlessness" is an unNewtonian doctrine. As Cotes says in the beginning of his preface to the Principia, "The weights of bodies at equal distances from the centre of the earth are as the quantities of matter in the bodies." In Newtonian doctrine, since bodies in LEO are only slightly displaced from the surface, their weights are only slightly reduced, compared to their weights on the surface.

[dayglored]

I would do that in a heartbeat! Of course, I’m now 60, my daughter is an adult, and if I died I would say I had a good life. It would be worth the risk. But they won’t let me be an astronaut with high blood pressure.....

[Ophiucus]

Way cool. Thanks for the post.

[left that other site]

I have been wanting to do that Since Alexei Leonov and Edward White did it.

I guess I shall just have to be content with riding my Harley.

[ixtl]

This picture should be next to “courage” in the dictionary.

[colorado tanker]

Open the pod bay doors, HAL.

I'm sorry, Dave . . .