Zarya - Soviet, Russian and International Spaceflight
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Miscellaneous Tracking


Tyneside, UK
2017 Apr 30
Sunday, Day 120

Maintained by:












Cosmos 2463 - Broken?

2010 August - Sven Grahn was monitoring the Swedish Prisma satellite pair transmitting at 400.550 MHz when he noticed a CW transmission at 400.530 MHz that exhibited a classic satellite Doppler curve.

The first challenge was to identify it because the frequency had no history. Further observations from the UK tied down the orbital period to 104-106 minutes and showed that it was in a polar orbit. It was something of a surprise when Ted Molczan analysed the observation timings and identified it as Cosmos 2463, a Russian Parus satellite.

400.530 MHz is not a known Parus transmission frequency. The first thought was that it might be a secondary payload but this did not seem likely.


Standard Parus Behaviour

Cosmos 2463 has a transmission at 149.940 MHz carrying almanac and time data. There is a CW signal at 399.840 MHz to aid Doppler-based tracking. They are standard Parus frequencies and are coherent in the ratio 8:3.


Further Developments at 400 MHz

A few days later, while monitoring the standard 400 MHz Parus frequencies from the Zarya location, a CW transmission at 399.977 MHz was logged. There was a further surprise when it too was traced to Cosmos 2463. Suspicion began to grow that there might be a problem with Cosmos 2463's transmission system. It was reinforced when two further frequencies, 399.150 MHz and 399.703 MHz, yielded signals.

400.530 MHz and 399.150 MHz are respectively 690 kHz above and below the 399.840 MHz operational frequency. Similarly the 399.977/399.703 MHz pair is at ±137 kHz.

2010 Late September, while monitoring another satellite, a stray transmission from Cosmos 2463 was logged at 400.117 MHz.


150 MHz - Problems Here Too

Cosmos 2463's almanac/time data transmission at 149.940 MHz also exhibits 'images' at other frequencies. The data transmission is repeated at 150.215 MHz and 149.665 MHz, symmetrically arranged 275 kHz above and below 149.940 MHz.


Possible Root of the Problem

The answer might simply be "age". Parus is in its declining years and Cosmos 2463 is from a limited stock of spare vehicles manufactured several years ago when the system was in its heyday.

Being in store for a time will have taken its toll, however good the storage conditions. Even if the satellite passed all tests prior to launch, minor deterioraion of components might have compromised its ability to withstand the ride to orbit and exposure to space.

The question is open as to whether the 'extra' transmissions were present immediately after launch 2010 April 27, or arrived sometime later. There is no unusual activity logged against Cosmos 2463 prior to August but, with so few radio observers, it is not surprising that it might have been missed.


Cosmos 2463 Frequency List

These are the frequencies that have been discovered. Other images might exist in pairs near both 400 MHz and 150 MHz - as detected at 400.171 MHz 2010 late-September. Any reports would be appreciated.

Freq (MHz) Satellite Mission Signal Type Notes
149.665 Cosmos 2463
(Parus)

2010-017A
36519
Navigation satellite. Broadcasts navigational almanac for the active Parus constellation to allow Naval users (principally submarines) to track the satellites in order to use the onboard messaging store/dump system. FM time and position information - sidebands at 3 kHz, 5 kHz and 7 kHz Duplicate of the standard 149.940 MHz transmission at a frequency 275 kHz below it. The transmitter is faulty.
149.940 Cosmos 2463
(Parus)

2010-017A
36519
Navigation satellite. Broadcasts navigational almanac for the active Parus constellation to allow Naval users (principally submarines) to track the satellites in order to use the onboard messaging store/dump system. FM time and position information - sidebands at 3 kHz, 5 kHz and 7 kHz Transmission contains an almanac for all active satellites in the constellation - coherent transmission at 399.840 plus duplicated transmissions at other frequencies around 150 and 400 MHz . The transmitter is faulty.
150.215 Cosmos 2463
(Parus)

2010-017A
36519
Navigation satellite. Broadcasts navigational almanac for the active Parus constellation to allow Naval users (principally submarines) to track the satellites in order to use the onboard messaging store/dump system. FM time and position information - sidebands at 3 kHz, 5 kHz and 7 kHz Duplicate of the standard 149.940 MHz transmission at a frequency 275 kHz above it. The transmitter is faulty.
399.150 Cosmos 2463
(Parus)

2010-017A
36519
Navigation satellite. Broadcasts navigational almanac for the active Parus constellation to allow Naval users (principally submarines) to track the satellites in order to use the onboard messaging store/dump system. CW carrier Duplicate of the standard 399.840 MHz transmission at a frequency 690 kHz below it. The transmitter is faulty.
399.703 Cosmos 2463
(Parus)

2010-017A
36519
Navigation satellite. Broadcasts navigational almanac for the active Parus constellation to allow Naval users (principally submarines) to track the satellites in order to use the onboard messaging store/dump system. CW carrier Duplicate of the standard 399.840 MHz transmission at a frequency 137 kHz below it. The transmitter is faulty.
399.840 Cosmos 2463
(Parus)

2010-017A
36519
Navigation satellite. Broadcasts navigational almanac for the active Parus constellation to allow Naval users (principally submarines) to track the satellites in order to use the onboard messaging store/dump system. CW - Doppler tracking beacon Coherent transmission at 149.940 MHz plus plus duplicated transmissions at other frequencies around 150 and 400 MHz due. The transmitter is faulty.
399.977 Cosmos 2463
(Parus)

2010-017A
36519
Navigation satellite. Broadcasts navigational almanac for the active Parus constellation to allow Naval users (principally submarines) to track the satellites in order to use the onboard messaging store/dump system. CW carrier Duplicate of the standard 399.840 MHz transmission at a frequency 137 kHz above it. The transmitter is faulty.
400.117 Cosmos 2463
(Parus)

2010-017A
36519
Navigation satellite. Broadcasts navigational almanac for the active Parus constellation to allow Naval users (principally submarines) to track the satellites in order to use the onboard messaging store/dump system. CW carrier Duplicate of the standard 399.840 MHz transmission noted late-September 2010. The transmitter is faulty.
400.530 Cosmos 2463
(Parus)

2010-017A
36519
Navigation satellite. Broadcasts navigational almanac for the active Parus constellation to allow Naval users (principally submarines) to track the satellites in order to use the onboard messaging store/dump system. CW carrier Duplicate of the standard 399.840 MHz transmission at a frequency 690 kHz above it. The transmitter is faulty.
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