December 23rd, 2011 by Roy W. Spencer, Ph. D.

I see this morning a news report of a metal ball falling out of the sky and landing in Namibia:

While the find seems to have baffled local authorities, it didn’t take me long to identify it as a satellite hydrazine propellant tank, made of titanium:

The size (14 inches in diameter) and weight (about 8 kg) match.

Lotsa stuff flying around in orbit these days, and eventually it all must come back down. Fortunately, most of it burns up before reaching the ground.

19 Responses to “Spaceballs!”

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  1. Sean says:

    Let’s hope the fuel is all gone. Hydrazine is nasty stuff.

  2. Mark Whitney says:

    The Gods Must Be Crazy in high-tech!

  3. tadchem says:

    The absence of red oxide (Fe2O3) or black oxide (Fe3O4) show there is no iron. Titanium is the likely material, which suggests Russian origin – they have access to a lot of titanium and know how to work it. That is some first class arc-welding on the seam!

  4. Claude Culross says:

    Or an ornament that fell off some alien’s Christmas tree!

  5. Merry Christmas Roy!
    And a Happy New Year!

  6. has an item on this. There is strong appearance that this is a Russian spherical tank, although there are signs of difficulty with identifying it to a particular spacecraft.

    As for a titanium piece of space junk – I consider it to be lucky to not get burned up during re-entry. It must have slowed down quickly, perhaps a bit like a parachute,
    due to low density from being mostly hollow.

    It appears to me that titanium is more combustible than iron, maybe roughly as combustible as zirconium (used in some flashbulbs, I forget which is used in many sparklers),
    though less combustible than aluminum and magnesium. Keep in mind how cutting torches work, and what steel wool can do!
    It appears to me that a piece of titanium space junk is lucky to not burn up. My guess is that a hollow sphere got slowed to a speed short of heating it to melting/combustion,
    and got airflow over it cooling it, before most of it can be burned away.

    Then again, should any uneven feature of this object or any uneven burning of it cause it to have its center of “drag force” to any side of its center of gravity, then the object would start rotating. Much of the rearward part of such object would have surface pressure less than nearby atmospheric pressure, and reduced to possibly negative temperature rise of local air. If the ball starts spinning,
    it may be slow to overheat.

    Especially should its spin be in the “underhand” (baseball pitch) direction, causing it to sink faster than if it was not rotating – in which case it gets into thicker air quicker, to spend less time moving fast enough in air
    to burn it or melt it, especially if it was spinning.

  7. The technologically illiterate lamestream media clowns (and that includes Glenn Beck’s The Blaze Web site) are all agog about how this thing is composed of an “alloy known to man.”

    An alloy? All the information discussed so far says that these spherical hydrazine propellant tanks are metallic Titanium. A couple of minutes with a file, and then a trip to a college analytical chem lab would tell enough about such a dingus’ composition that you’d have confirmation that it came out of an EADS parts catalog.

  8. Rob says:

    The more amazing thing to me is that it looks like it landed and didn’t bust into pieces. Falling from that far and looking to be intact, at least from the outside, seems quite remarkable!

    Merry Christmas to you and your family, Dr. Spencer.

  9. Gilles says:

    Could it be a Phobos Grunt piece ?

  10. Hans Verbeek says:

    One down: over 3000 to go.
    We have clearly passed peak-satellite.

  11. Jeff Id says:

    Hydrazine tank was my first guess too.

  12. bob paglee says:

    Is this a warming message from the Plutonian Chief Planetorianist that his tribe rejects Earth’s crass demotion of Pluto from Planet to — err… well, what is it now? Just another orbiting pile of rock?

    Maybe the next spherical one from Pluto will be much bigger if Earth doesn’t repent.

  13. bob paglee says:

    On second more serious thought, at least we should be glad it reentered instead of smashing into another more viable U.S. satellite.

  14. Andyj says:

    It’s welded with “electron beam welding”. Don’t imagine this Russian component was not used to place a US or EU item into space for one minute. This is where the Russians are world experts with no peer.

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