Two news about GLONASS: one good, the other bad

the Good news here's: all three satellites, which on 14 December 2009, launched into space (how are we watched in the video) — they are all now in the ranks, all of them are now working successfully. The last (the third of them) were entered into the system on January 30, svidetelstvuet the website of IAC kvno TsNIIMash.

The bad news is that's what: although now eighteen spacecraft, the availability of the navigation signal (that is, that proportion of the full time of day during which navigation is possible with the desired accuracy) are now actually below, the January 19, when was 17.

_{Configuration of satellites izmenilsja during this time, not only because of the advent of new satellites, but also due to the fact that some of the companions stood up on maintenance, and some finished it, and exit the system is now preparing two satellites instead of one.}

Let's compare.

That's what the situation was with availability January 19:

_{This is my own backup copy of the illustration. Now blogoshpere from 19 January can also show the previous state of availability of navigation, and perhaps its current state, because then blogozapisi I kept the illustration from the website of the IAC kvno TsNIIMash, just coralita URL.}

As you can see, on the 19th of January in most parts of Russia, the NAV was available as a 95% 99% of days, that is, the interruption was approximately one hour per day.

But what is the situation now:

_{This is also a backup copy of the illustration, so in the future to maintain the current system state.}

As you can see, 2 February in most parts of Russia navigation is available 80% 95% of day, that there are shortages of approximately from one hour to five hours a day.

Therefore, the GLONASS system is still not always enough to be only 75% filled with satellites (18 of 24 pieces) to cover with its signal the whole of Russia. Much depends not only on the number of satellites and their distribution of orbital planes.

It's good that in the current February there will be another launch three satellites to replenish the GLONASS. Indeed, without it, the prospects of the system would not look radiant. And (four weeks after launch, judging by January), the orbital group will continue to grow with operational spacecraft.

By the end of March GLONASS will be able to begin to cover Russia absolute availability.

Article based on information from habrahabr.ru