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Russia Lost a $45 Million Satellite Because 'They Didn't Get the Coordinates Right' (gizmodo.com)
Last month, Russia lost contact with a 6,062-pound, $45 million satellite. Turns out, that happened because the Meteor-M weather satellite was programmed with the wrong coordinates. Gizmodo reports: On Wednesday, Russian Deputy Prime Minister Dmitry Rogozin told the Rossiya 24 state TV channel that a human error was responsible for the screw-up, according to Reuters. While the Meteor-M launched last month from the Vostochny cosmodrome in the Far East, it was reportedly programmed with take-off coordinates for the Baikonur cosmodrome, which is located in southern Kazakhstan. "The rocket was really programmed as if it was taking off from Baikonur," Rogozin said. "They didn't get the coordinates right." And the rocket had some precious cargo on board: "18 smaller satellites belonging to scientific, research and commercial companies from Russia, Norway, Sweden, the U.S., Japan, Canada and Germany," Reuters reported.
From what I can find the GPS system doesn't work nearly as well in space - especially if you're above the GPS orbits. Might be serviceable in low orbit, but why bother with all the potential failure modes when you already know exactly where it starts from. You did double-check that before the launch, right?
Problem one is that the GPS satellites tight-beam their signals at the Earth to avoid wasting energy - picture a cone roughly twice as tall as it is wide, with the Earth's cross-section filling it's base, and a GPS satellite at it's tip. That's the space containing the signal, and there's going to be an awful lot of space between those cones as you gain altitude. Though there is typically a bit of "overshoot" around the edges as well, so things aren't as bad as they might be.
Problem two is that the faster you're moving the harder it is to lock on to the signal - think of how much longer it takes for a recently powered-off GPS device to establish its location while driving down the highway versus when you're parked. And then figure LEO orbital speed is about 17,450mph. No doubt it could still be done - but might be expensive and/or unreliable.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Civilian GPS equipment is actually designed to cut out above a certain velocity and altitude. Generally the velocities and altitudes involved in weapons delivery applications. This is, of course, designed to prevent somebody building an ultra cheap Balistic Missile guided by GPS OR an ultra fast rocket propelled missile guided by GPS. Go too fast OR too high and your guidance goes from accurate to estimate to guesstimate to "ooh, look at the flowers"
These kinds of errors are not just related to Russia.
Mars Climate Orbiter probe lost due to Math error:
English to Metric math conversion error
https://edition.cnn.com/TECH/s...
https://mars.nasa.gov/msp98/ne...
http://articles.latimes.com/19...
ExoMars Schiaparelli lander crashed due to failure to recognize the proper height.
http://spaceflight101.com/exom...
https://www.forbes.com/sites/b...
Have a read of the story, that is WRONG AS WRITTEN.
> While the Meteor-M launched last month from the Vostochny cosmodrome in the Far East, it was reportedly programmed with take-off coordinates for the Baikonur cosmodrome, which is located in southern Kazakhstan.
No, no, no... NO! The word "it" refers to the Meteor-M satellite. The satellite was NOT programmed incorrectly; it was the launcher that was mis-programmed, as the following sentence clarifies.
> "The rocket was really programmed as if it was taking off from Baikonur," ....
Looking at space, radio, science and computing from a 'down-under' amateur enthusiast perspective.
In the Soyuz/Fregat launch vehicle, the first three booster stages of the rocket and the Fregat upper stage have their two separate guidance systems controlled by their own gyroscopic platforms. The guidance reference axis used by the gyroscopes on the Soyuz and on the Fregat had a 10-degree difference. The angle of a roll maneuver for rockets lifting off from Baikonur, Plesetsk and Kourou, which was required to guide them into a correct azimuth of ascent, normally laid within a range from positive 140 to negative 140 degrees. To bring the gyroscopic guidance system into a position matching the azimuth of the launch, its main platform has to be rotated into a zero-degree position via a shortest possible route. The ill-fated launch from Vostochny required a roll maneuver of around 174 degrees (which was apparently conducted from the 5th to 22nd second of the flight), and with an additional 10 degrees for the Fregat's reference axis, it meant that its gyro platform had to turn around 184 degrees in order to reach the required "zero" position.
In the Soyuz rocket, the gyro platform normally rotated from 174 degrees back to a zero position, providing the correct guidance. However on the Fregat, the shortest path for its platform to a zero-degree position was to increase its angle from 184 to 360 degrees. Essentially, the platform came to the same position, but this is not how the software in the main flight control computer on the Fregat interpreted the situation. Instead, the computer decided that the spacecraft had been 360 degrees off target and dutifully commanded its thrusters to fire to turn it around to the required zero-degree position. After the nearly 60-degree turn at a rate of around one degree per second, the Fregat began a preprogrammed trajectory correction maneuver with its main engine. Unfortunately, the spacecraft was in a wrong attitude and, as a result, the engine was fired in a wrong direction.
Nothing about the vehicle or the satellite being "programmed with the wrong coordinates", just an edge case for the control system (a little bit like with the Ariane 5 incident).
Ezekiel 23:20
Which satellites, exactly, get anywhere near a LaGrange point? Nothing in orbit, that's for sure.
I ask because it sounds like you're throwing out "space" words without knowing what they mean.
The nearest LaGrange points are very very far from satellites. Geosynchronous satellites are ~35,000 km (the highest orbit we really use), compared to the L4/L5 LaGrange points at ~380,000 km. Nothing is going to just drift over there. Anything in Earth orbit is either staying there for a long time or burning up on its way down.
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According to the latest ruleset, this post should be modded as Vorpal Flamebait +5.