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>Here's a useful experimental determination of c for those who have access
>to a big-dish high-power well-steered spatially diverse uplink that can
>pick out a signal that's 2^-71 watts at 16 baud.
>
>
>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>Sat, 2 Mar 2002
> From Larry Lasher, Pioneer Project Manager
>Subject: Pioneer-10 30 Year Launch Anniversary Track
>
>Pioneer-10 was successfully contacted today. Yesterday, about 3pm PST a
>200 Kw uplink transmission from Goldstone California, the 70 meter DSN
>antenna DSS-14, was sent to Pioneer-10 and 22 hours later in Madrid Spain
>at the DSN 70 meter antenna DSS-63 the confirmation of contact was
>received. From a distance of 79.7 AU DSS-63 acquired the signal on time at
>about -183 dbm. They spent an hour peaking the signal (-178.5 dbm) and
>then they were able to lock up telemetry at 16 bps at an SNR of -0.5
>db. Tracking continued until the elevation was about 20 degrees but enough
>telemetry was received to verify the state of Pioneer-10. Incidentally,
>the SETI institute also saw the signal from Arecibo in Puerto Rico. For
>years they have used Pioneer-10 as a reference for their investigations.
>
>The spacecraft is still healthy. The power is still sufficient to support
>the loads with the bus voltage at about 26 volts (nominal is 28). The
>uplink from DSS-14 was received by the spacecraft at -131.7 dbm. The
>spacecraft is extremely cold, with many of the temperature readings at the
>bottom of their scales. Two commands were sent yesterday from Goldstone
>and both were confirmed to have been executed by the spacecraft. One
>scientific instrument is still on, the Geiger Tube Telescope, and Dr. James
>Van Allen, the PI, will be happy to hear he has some more data to look at.
>
>Thirty years ago the first mission to explore the outer planets,
>specifically the planet Jupiter, was launched from KSC. Many of the people
>who designed, built and flew the spacecraft have passed on but Pioneer-10
>continues. From ARC and the Pioneer Project we send our thanks to the
>many people at the DSN (Goldstone and Madrid) and JPL who made it possible
>to hear the spacecraft signal again.
>
>Dave Lozier, Pioneer Flight Director
>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>Brian Whatcott
> Altus OK Eureka!
Howdy,
I have a feeling that the value of c was used to determine the 79.7
AU distance to the Pioneer-10. Therefore you can't turn it around
and find c from this data.
Good Luck,
--
Herb Schulz
(herbs@interaccess.com)