At 04:25 PM 8/1/2006 +1200, Simon Lyall wrote:
On Tue, 1 Aug 2006, neil gardner wrote:
However on a serious note there was a time I recall that IHUG warned about an expected outage (on Satnet) due to particularly bad solar flare activity... They were able to predict this in advance so it MAY not have been completely imaginary.
Those were "Sun Outages" which is when the Sun is directly behind the satellite as viewed from the ground station. They happen around the equinoxes, ie not this week.
I can confirm they happen. When we webcast the rowing at Karapiro last year we lost the sat link at 11:50 each day for one hour. It was equinox and the sat is about 5degrees off due north. The providers all said it was my temporary install, then it was thermal, then we looked at the NSS5 website and their sun tables documented it well - just they hadn't read their own webpages. The outage lasted about an hour, but that could have been partly due to my mad panic to get something going again. I now use 2 dishes on two different satellites and balance the traffic between them. IPSTAR being 20deg above the horizon means you get issues at twilight. (which means you go have dinner and align it afterwards, in the dark) The sat operators refer to it as "sun strike". Rich