How a Swedish engineer saved a once-in-a-lifetime mission to Titan (2004)(spectrum.ieee.org) |
How a Swedish engineer saved a once-in-a-lifetime mission to Titan (2004)(spectrum.ieee.org) |
> Huygens was programmed to transmit telemetry and scientific data to the Cassini orbiter for relay to Earth using two redundant S-band radio systems, referred to as Channel A and B, or Chain A and B. Channel A was the sole path for an experiment to measure wind speeds by studying tiny frequency changes caused by Huygens's motion. In one other deliberate departure from full redundancy, pictures from the descent imager were split up, with each channel carrying 350 pictures.
>As it turned out, Cassini never listened to channel A because of an operational commanding error. The receiver on the orbiter was never commanded to turn on, according to officials with the European Space Agency. ESA announced that the program error was a mistake on their part, the missing command was part of a software program developed by ESA for the Huygens mission and that it was executed by Cassini as delivered.
>The loss of Channel A means only 350 pictures were received instead of the 700 planned. All Doppler radio measurements between Cassini and Huygens were lost as well. Doppler radio measurements of Huygens from Earth were made, though not as accurate as the expected measurements that Cassini would have made; when added to accelerometer sensors on Huygens and VLBI tracking of the position of the Huygens probe from Earth, reasonably accurate wind speed and direction measurements could still be derived.
http://en.wikipedia.org/wiki/Huygens_(spacecraft)#Channel_A_...
Happily enough this was possible to do without using too much fuel, and indeed Cassini had more fuel available than planned, as the original launch and early course corrections had been so precise that fuel planned for course correction burns was available for other uses. One of the consequences of all of this is that Cassini is still operational today, more than 5 years passed the planned end of it's mission.
But a work round was found. And I have a really good example for teaching resolving vectors...
(Question: What does his nationality have to do with it though? Seems like an odd addition to the headline.)
Seemed strange to me too. There was another instance of this a few days ago with the article "How British satellite company Inmarsat tracked down MH370" [1]. Is this a journalistic practice?
Scientific funding, however, does. This is one reason why it is crucial that taxpayers can connect with scientific success. For ESA this is problematic because their success gets distributed, consequently most Europeans might not even know it exists.
Saudi Arabian programmer fixes XSS vulnerability in Rails
German engineer (who also holds a USA passport due to his American mother) finds new algorithm for error-detection of communications over rusty wires
Programmer from Brazil, now a British citizen but also holding a Canadian passport via his wife, discovers method for instant startups of apps on the JVM.
Randall Munroe has made fun of this and similar headline-writing trends:
Here's an example: look at the coverage of the missing Malaysia airlines plane.
Every single article I've read starts with this: "[insert nationality] experts have [insert what they've done]".
EDIT: Of course, that's necessary for journalism. It's information. How else are you going to distinguish between experts?
Also, I guess something like Manchester encoding wasn't use because of the data rate limitations? IIRC Manchester encoding is self-clocking, which seemed like the issue here.
Is there any place you can go to escape the forces of willful ignorance?
I am surprised that NASA would allow a piece of hardware on a spaceship that they do not have the specs for. Unless NASA/ESA do very extensive testing, this seems like a terrible practice.
In practice, the alternative to geographic tribalism isn't some broadly-inclusive egalitarianism. It's relatively wealthy and educated folks like us receding into circles with other relatively wealthy and educated folks.
I don't want to live in a world where children are taught to betray their parents in favor of their state, where children are taught to report on their parents for their crimes, where brothers treat each other as strangers, where husband betrays wife and vice versa, at the same time. I've already read about it in 1984.
The harm in suppressing this aspect of humanity comes from having to involve the state. It takes the state to educate children to report on their parents crimes. It takes the state to force children to attend schools to study the same subjects. It takes the state to extract wealth from parents to distribute it to other children. It takes the state to enact taxes on children to distribute their income amongst other parents. Taken to the extreme - you'll get a very big, very powerful state, because it must involve itself in everyone's personal relationships, to ensure equality amongst all. And with a big state, you get corruption, you get misallocations of capital, you get a concentration of power, all of which would lead to a state that would monitor its citizens every communication, to protect its power in actuality, and to maintain equality and protect its citizens in name. And, as you reduce every person's natural relationships, people will form relationships with others, leading to divisions not amongst genetic or even geographic lines, but amongst other arbitrary lines such as class and wealth, government and private. As a group of people gain control of state, the actions of the state will begin to benefit some, but not others, arbitrarily, so that in actuality equality (in wealth, status, whatever) will always only be an illusion, and inequality will always manifest itself in other ways, so that all those resources supporting a very big state to maintain equality, are mostly wasted, except in so far as it provides an illusion of equality, which it can maintain for only so long.
Oh, wait.
I see part of the problem as the intensity of tribalism or reactions to it. People getting together because of shared preferences, locations, or ideas seems okay. Getting carried away causes problems.
Go ahead and feel proud you've defended your mind from reasoning another person's thoughts and thinking up a rebuttal based on reasonable arguments. lol. :)
Yeah, accuse me of pride. There's "takes one to know one", and then there's this.
> thinking up a rebuttal based on reasonable arguments.
Your post is rebutted by history. When you have a reasonable argument to make, go ahead and make it. Until then, your wall of sarcastic text is best answered by "a dash of sarcasm".
How is it rebutted by history? Tell me the specific historical events you have in mind.