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Old June 1st 15, 02:18 AM posted to sci.space.science
Jeff Findley[_6_]
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Default Planetary Society Blog for Saturday 30 May 2015

In article , says...

On 5/31/2015 9:07 AM, The Planetary Society via sci.space.science Admin
wrote:
Planetary Society Blog

///////////////////////////////////////////
For LightSail Test Mission, Waiting is the Hardest Part

Posted: 29 May 2015 02:02 PM PDT
http://www.planetary.org/blogs/jason...dest-part.html


The Planetary Society's LightSail spacecraft is now entering its second
week of silence.


Shades of the old ordeal with the Mars Climate Orbiter. I read elsewhere
that the probe launched with a known issue in its software.
That being that live ping transmissions from the spacecraft were being
logged in memory, until that memory was exhausted and then the software
crashed. Seems unlikely they will be able to revive this craft unless
there was a secondary control channel to allow remote restart of the
processor. That appears to not be the case here. I'd say this one is
one and done.

What I find of note is that there was apparently no use of a watchdog
timer. That would have forced the probe to restart on its own once the
hardware watchdog triggered. Seems like a rookie mistake. Ah well,
hopefully the Planetary Society didn't blow the budget on this one.
Another kickstarter folks?



Planetary Society Regains Communication With LightSail Spacecraft
MAY 31, 2015 8:14 AM ET
http://www.npr.org/sections/thetwo-w...857/planetary-
society-regains-communication-with-lightsail-spacecraft

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer