Re: [amsat-bb] BY70-1

30 Dec 2016

      I put the parameters from yesterday's TLEs into NASA's DAS software. The
mass is listed at 2 kg, so the unknown variable is the cross sectional
surface area. It's a 2U cubesat with deployed solar panels. With one
estimate, I got 6 days, which is obviously wrong. With another estimate, I
got 96 days.
73,
Paul, N8HM
On Fri, Dec 30, 2016 at 14:45 Nico Janssen hamsat@xs4all.nl wrote:
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As long as we don't have stable TLEs it is not possible to perform
an analysis to determine the expected lifetime. But my initial
guestimate would be somewhere between 2 and 6 months.
73, Nico
On 30-12-16 19:43, Greg D wrote:
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18:20 pass not as strong as prior passes.  Only got a few moments of
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full-quieting audio.  Contacts with W5ACM and KC7M.  As before, the
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second half of the pass was much better (nothing heard at all until just
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before indicated TCA), so perhaps the bird is late compared to the
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Keps.  Worked it almost into the ground before LOS.  I'm using
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2016-083C, updated from Celestrak right before the pass.  Playing with
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polarization seemed to help, but I'm assuming the bird's antennas are
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linear, right?  Possibly my relays are getting dirty.
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One question, for scale...  We know that the satellite will not last
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"long", given it's crippled orbit.  How long?  Days?  Weeks?  Months?
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Greg  KO6TH
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Nico Janssen wrote:
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If you are still using yesterday's TLE set, then you will indeed find
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that BY70-1 is now about half a minute earlier. The problem is that
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the TLEs for this satellite are not stable yet in the first days after
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the
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launch. The right value for e.g. the decay rate has not yet been
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established. So for the time being you need to make sure you use the
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most recent TLE set that is available.
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By the way, the two SuperView satellites are now using their own
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propulsion system to increase their altitude, preventing an early decay.
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As BY70-1 does not have any propulsion, it is stuck in its low orbit.
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73,
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Nico PA0DLO
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On 30-12-16 13:42, PY5LF wrote:
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Hi
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We had a low pass over here minutes ago and i felt the keps BY70-1 are
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wrong .
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I start to hear 25 seconds before . Does anyone feels the same ?
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73
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to all interested persons worldwide without requiring membership.
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are solely those of the author, and do not reflect the official views
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Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available
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to all interested persons worldwide without requiring membership.
Opinions expressed
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are solely those of the author, and do not reflect the official views of
AMSAT-NA.
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Not an AMSAT-NA member? Join now to support the amateur satellite
program!
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Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb

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to all interested persons worldwide without requiring membership. Opinions
expressed
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AMSAT-NA.
Not an AMSAT-NA member? Join now to support the amateur satellite program!
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Re: [amsat-bb] BY70-1

Paul Stoetzer