ExoMars and Schiaparelli
Discussion
ash73 said:
Toaster said:
Philea did land and bounced
...and crashed.= successful failure.
The issue seems to me in getting the sequence of entry and landing events to occur reliably and in the right order. Different aspects of the landing sequences may have failed on the various landing attempts - but there does seem to be a pattern in that the sequences aren't being completed properly.
Two factors would enable NASA to photograph the spot quickly -
a) they knew exactly the co-ordinates of the target land site
b) one of their orbiting spacecraft were in a position to take a picture as it passed overhead the site
The latter is a matter of luck because it would have been a coincidence that a pass directly overhead the site in daylight was scheduled only a few hours after the probe was supposed to have landed.
On another occasion it might have been days or weeks before an orbiting spacecraft passed directly overhead the site in daylight hours.
Updated to add - next week, NASA's MRO (Mars Reconnaissance Orbiter) will pass directly overhead the site and point its HiRise camera at the lander wreckage and this will give much better detail than the comparatively low resolution shot released today. ESA think that the probe impacted at around 300 mph.
a) they knew exactly the co-ordinates of the target land site
b) one of their orbiting spacecraft were in a position to take a picture as it passed overhead the site
The latter is a matter of luck because it would have been a coincidence that a pass directly overhead the site in daylight was scheduled only a few hours after the probe was supposed to have landed.
On another occasion it might have been days or weeks before an orbiting spacecraft passed directly overhead the site in daylight hours.
Updated to add - next week, NASA's MRO (Mars Reconnaissance Orbiter) will pass directly overhead the site and point its HiRise camera at the lander wreckage and this will give much better detail than the comparatively low resolution shot released today. ESA think that the probe impacted at around 300 mph.
Edited by Eric Mc on Friday 21st October 22:51
Eric Mc said:
Two factors would enable NASA to photograph the spot quickly -
a) they knew exactly the co-ordinates of the target land site
b) one of their orbiting spacecraft were in a position to take a picture as it passed overhead the site
The latter is a matter of luck because it would have been a coincidence that a pass directly overhead the site in daylight
a) ESA knew the trajectory of their craft and shared it with NASA so its not hunt the needle and b) Not luck but the appliance of Science a) they knew exactly the co-ordinates of the target land site
b) one of their orbiting spacecraft were in a position to take a picture as it passed overhead the site
The latter is a matter of luck because it would have been a coincidence that a pass directly overhead the site in daylight
Edited by Eric Mc on Friday 21st October 22:51
Edited to say they probably use pattern recognition software to help spot changes rather than just rely on the human Eye which speeds up object identification
Edited by Toaster on Saturday 22 October 18:59
MartG said:
Luck - NASA did not alter MRO's orbit to cover the area so, while it would sooner or later have been able to image the area, it was a matter of luck that it could do so within hours of the landing attempt
Erm no I don't think so luck implies that you have no idea where the craft was in relation to the orbiter, ESA knows what the trajectory was and a calculation can be made from the telemetry. This is the MRO's path and if it had been in area it could not see then NASA would have been able to say "in x days weeks we will be able to take a view" In the same way Luck does not come in to it. ESA state:
"A closer look at these features will be taken next week with HiRISE, the highest-resolution camera onboard MRO. These images may also reveal the location of the front heat shield, dropped at higher altitude." So this means that more is known about what they are doing than"Luck"
http://www.esa.int/Our_Activities/Space_Science/Ex...
Oh and you can find the MRO's position here http://mars.nasa.gov/mro/mission/whereismro/
MartG said:
Luck - NASA did not alter MRO's orbit to cover the area so, while it would sooner or later have been able to image the area, it was a matter of luck that it could do so within hours of the landing attempt
Don't bother debating with T. He'son another planet to the rest of us.Toaster said:
MartG said:
Luck - NASA did not alter MRO's orbit to cover the area so, while it would sooner or later have been able to image the area, it was a matter of luck that it could do so within hours of the landing attempt
Erm no I don't think so luck implies that you have no idea where the craft was in relation to the orbiter, ESA knows what the trajectory was and a calculation can be made from the telemetry. This is the MRO's path and if it had been in area it could not see then NASA would have been able to say "in x days weeks we will be able to take a view" In the same way Luck does not come in to it. ESA state:
"A closer look at these features will be taken next week with HiRISE, the highest-resolution camera onboard MRO. These images may also reveal the location of the front heat shield, dropped at higher altitude." So this means that more is known about what they are doing than"Luck"
http://www.esa.int/Our_Activities/Space_Science/Ex...
Oh and you can find the MRO's position here http://mars.nasa.gov/mro/mission/whereismro/
MartG said:
As usual you're missing the point - yes, as I said, MRO would be able to image the site at some point in time, as NASA knew exactly where it was. However, as I also said, it was luck that MRO was able to image the site in daylight so soon after impact. MRO is in a sun-synchronous polar orbit so it is possible that a delay of several days may have occurred before such an image could be taken.
Luck does not come in to it, the orbiter was there. had the capability to take low re images these were processed and the area found where the objects are and will at a later date have a Hi res image taken and processed. Had it taken the images a day later is that 'bad luck'?So in essence thats not luck thats Science, was it luck or science there is a MRO in orbit anyway? Was it luck or science ESA knew where the lander entered the atmosphere and shared it with NASA (NASA wouldn't have known exactly where it was it still had to be found) .
Next you will be telling us that the MRO controller had a lucky rabbits foot and thats why they spotted it so quickly
Toaster said:
MartG said:
As usual you're missing the point - yes, as I said, MRO would be able to image the site at some point in time, as NASA knew exactly where it was. However, as I also said, it was luck that MRO was able to image the site in daylight so soon after impact. MRO is in a sun-synchronous polar orbit so it is possible that a delay of several days may have occurred before such an image could be taken.
Luck does not come in to it, the orbiter was there. had the capability to take low re images these were processed and the area found where the objects are and will at a later date have a Hi res image taken and processed. Had it taken the images a day later is that 'bad luck'?So in essence thats not luck thats Science, was it luck or science there is a MRO in orbit anyway? Was it luck or science ESA knew where the lander entered the atmosphere and shared it with NASA (NASA wouldn't have known exactly where it was it still had to be found) .
Next you will be telling us that the MRO controller had a lucky rabbits foot and thats why they spotted it so quickly
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