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View Full Version : Telstar 401, A Ghost of Space Weather Past



SDO
24th June 2016, 19:30
https://1.bp.blogspot.com/-CvufH8EYxtU/V22Ez2_P8sI/AAAAAAAAA64/nkiSrCxtLtcX0zpcY4lX5KjC4okSfebiACLcB/s320/telstar-401__1.jpg (https://1.bp.blogspot.com/-CvufH8EYxtU/V22Ez2_P8sI/AAAAAAAAA64/nkiSrCxtLtcX0zpcY4lX5KjC4okSfebiACLcB/s1600/telstar-401__1.jpg)
Earlier the week we received our conjunction report that lists satellites that will pass close to SDO. Our inclined geosynchronous orbit means there aren't a lot of satellites near SDO, but every couple of months one will come within 20 km (12 mi) of our spacecraft. This week saw the return of Telstar 401 to our list (see the picture at left.) Telstar 401 is a large telecommunications satellite that failed January 11, 1997, and has since drifted around the geostationary belt of satellites. This is not a small satellite, the solar panels stretch about 60 ft across. It's good to know the other satellite is around, but it would be better if was moved to a graveyard orbit well outside of the geostationary belt.

https://2.bp.blogspot.com/-c0krcoSAH1E/V22FcSvlh-I/AAAAAAAAA7A/tItdbdUlzKEmTKKhEDp3nwZBIjIHQ5PhwCLcB/s320/19970106_185010_lasc2rdf.png (https://2.bp.blogspot.com/-c0krcoSAH1E/V22FcSvlh-I/AAAAAAAAA7A/tItdbdUlzKEmTKKhEDp3nwZBIjIHQ5PhwCLcB/s1600/19970106_185010_lasc2rdf.png)
It is possible that Telstar 401 failed because of the activity created by a coronal mass ejection that rose off the Sun on January 6, 1997. (The gray picture at left shows what the CME looked like at 1850 UTC on that date.) The CME is the white arc moving down from the occulting disk. It is called a halo CME because we see it as a ring around the Sun, which means it is heading straight towards Earth!
The impact of the CME was not very dramatic when it reached Earth a few days later. But the energies of the radiation belt protons and electrons were increased enough that they caused an electronic component to arc and fail. There were several attempts to revive Telstar 401, but it was eventually declared a loss.
According to the Union of Concerned Scientists, there are almost 500 satellites currently operating in geosynchronous orbits about the Earth. Most of them are in the geostationary belt that allows them to appear stationary in the sky. There are about 100 defunct satellites in graveyard orbits further away from the Sun. But it is the failed satellites and spent boosters that blunder along and show up on the SDO conjunction report every month or so.
Telstar 401, a true ghost of space weather!

More... (http://sdoisgo.blogspot.com/2016/06/telstar-401-ghost-of-space-weather-past.html)

Cidersomerset
24th June 2016, 19:37
Telstar : The Tornados 1962


R0jUvufQgQo


Published on 22 Mar 2012

"Telstar" is a 1962 instrumental record performed by The Tornados.It was the first
single by a British band to reach number one on the U.S. Billboard Hot 100, and
was also a number one hit in the UK.

Telstar 1: First Private Communication Satellite - 1963 Space Documentary - WDTVLIVE42

https://www.youtube.com/watch?v=9vdf_Y-zFcM

Published on 2 May 2014
Telstar 1 was an experimental active communication satellite built by Bell Systems.
It was launched with assistance from NASA on 10 July 1962. Approximately 400
transmission sessions were conducted by the satellite with multichannel telephone,
telegraph, facsimile, and television signals in the 6 month period after Telstar was
launched. Hundreds of technical tests and measurements were also made which
would help later satellites revolutionise the communications industry. During
November 1962 the command subsystem on the satellite failed. A brief restoration
of services was made in early 1963, however within 6 weeks the command
subsystem again failed. The cause of the failures was due to degradation of
transistors, some believe this caused by Van Allen belt radiation while others
attribute the failures to American & Soviet nuclear weapons tests in the upper
atmosphere.