Holding On To Hope For Beagle 2

slasher999 writes "Scientists are still keeping their hopes up that they will be able to revive Beagle via the Mars Express mothership on 4 January. On that date the ship will be in the correct orbit and may then be able to revive the lander. Current theroies as to what may have gone wrong include the possibility that the landers on-board clock is incorrect and that the lander has been transmitting at incorrect times. Funny, I thought I heard that as of yesterday the batteries on the lander would have been depleted unless the lander had received an order to recharge its batteries."

Comments

Pillinger's statements are ridiculous...

[mbone]

This is ridiculous, and I for one cannot believe that Prof. Pillinger keeps saying it.

Unlike the NASA orbiter, which might conceivably not be able to understand the Beagle's transmission, Jodrell Bank is looking for its radio carrier (i.e., just for the existence of a transmission at all). It should be able to see it. That's what radio telescopes do, after all - and Jodrell Bank has been looking at space probes since the 1960's.

Moreover, all of Mars is well within a Jodrell Bank beamwidth at 500 MHz, so it doesn't matter where the thing is on Mars - Jodrell Bank should see it. And it's too much to believe that operators at Jodrell Bank, Westerbork and Stanford all screwed up such a simple measurement.

This spacecraft is almost certainly lost; I would rate it's chance of recovery at much less than one per cent.

Re:Pillinger's statements are ridiculous...

[sjames]

so it doesn't matter where the thing is on Mars - Jodrell Bank should see it.

Unless it's transmitting at the wrong time of (Martian) day when it's directional antenna is pointing away from Earth and occluded by Mars itself.

Without a doubt, none of this bodes well for Beagle 2, but since most of the effort and money has been spent already, a few man hours spent trying to salvage the mission is well worth it.

The next most likely time to make contact will be Jan 4th when it starts transmitting continuously. At that point, we will know that IF it does transmit, at some point the signal will be there when it is directed in the general direction of Earth.

Re:Can Stanford read -my- CPU's EM field too?

[anubi]

I'm sure they could see your computer's EM field. Easily!

I see my own all the time! You see, I have a TV in the next room still on rabbit ears. When I turn my computer on, channels 2, 4, and 5 become virtually unwatchable because of the processor clock harmonics being emitted in the TV channel spectrum.

Believe me, you might be surprised how much muss and fuss manufacturers go through to make sure they don't emit more EMI than some legal limit, much like auto manufacturers go through the hoops trying to minimize emissions.

The trick they are apt to use on Mars is to use several antennas at the same time to lock into the unit on Mars. Sure, there is a lot of ambient noises, and thats why the multiple antennas - you know exactly what phase delays as the signal arrives at each antenna to expect ( beamformer ). You only pay attention to the signals which arrive at the proper delays to each antenna. Being you know what the processor loop on Mars is doing, you can correlate against that same pattern . When you get correlation to that pattern showing up at the correct time displacements to each antenna, bingo. The unit on Mars is the only one that could emit the signal such that the constraints on the digital filters at the receivers here on Earth are met.

I am not on the team to do this, I am speculating on how I would attempt to do so. I do know computers are terribly noisy in the RF area, and because they emit a peculiar recognizable racket in the RF spectrum in an area that is by nature pretty quiet, it should be "relatively" easy to find. Especially one hung in a tight loop.

If you browse around for "pseudorandom noise generators", also known as "linear feedback shift registers", you will see a lot of tie-ins to "spread spectrum" communications, with technologies for digging signals out of the noise by taking advantage of correlation to known patterns.

Re:Nigerian scam anyone

[Wavicle]

design a half-assed re-entry method that is unproven

The Mars Pathfinder mission proved that a drag parachute plus impact absorbing air bag are effective mechanisms for touching down safely on mars.

without any type of backup.

What space vehicle to planetary atmospheric insertion system has ever been designed with a backup? When things go wrong during insertion, the result has always been loss of the vehicle. Even for vehicles whose precious cargo is living, breathing, humans.