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Old February 12th 13, 11:42 PM posted to uk.sci.astronomy
Dr J R Stockton[_193_]
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Default asteroid 2012 DA14 next week

In uk.sci.astronomy message
..12.10, Thu, 7 Feb 2013 20:15:55, Sjouke Burry posted:

"N_Cook" wrote in :

If I go out on Valentine's day next week with binoculars and clear sky
at the Plough and manage to see this object going zenithwards across
the handle of the pan-handle 21:00 to 22:00 or so, will it be varying
brightness from tumbling. ?
If it is tumbling before near earth encounter would that
gravitational encounter stop the the tumbling of an asymetric object?




Yes.
No.



I would expect that a non-tumbling asymmetric asteroid approaching from
infinity would be tumbling after the encounter. Gravitational motion is
time-reversal symmetric. Therefore an asteroid approaching from
infinity with just the right tumble would not be tumbling when it
finally reached infinity again. So only rather probably No.

IIRC : Consider not Niven's "Neutron Star" itself, but comments made
after its publication, such as in
http://en.wikipedia.org/wiki/Neutron_Star_%28short_story%29#Notes blob
2.

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