#THE MARTIAN SPACECONTROL FULL#
#THE MARTIAN SPACECONTROL CODE#
#THE MARTIAN SPACECONTROL PLUS#

As the MAV teeters dangerously, mission commander Melissa Lewis has no choice but to take off without completing the search for Watney. He is flung out of sight by the wind and presumed dead. During the hurried evacuation, an antenna tears loose and impales astronaut Mark Watney, a botanist and engineer, also disabling his spacesuit radio. After only six sols, an intense dust and wind storm threatens to topple their Mars Ascent Vehicle (MAV), which would trap them on the planet. But it's possible that he encountered rough terrain or mechanical problems with the rover early-on, and sped up significantly during the last 2/3 of the trip.In the year 2035, the crew of NASA's Ares 3 mission have arrived at Acidalia Planitia for a planned month-long stay on Mars. One might expect at least another 25 days' travel to reach Pathfinder if one assumes his speed is constant over the Martian terrain. A mere two days later, on Sol 94, he is at the Pathfinder site. You can clearly see that, based on those points, Mark has covered less than a third of the distance in 13 days. Kapoor makes a mark at the Hab, then asks Mindy where Mark is he makes a second mark there, then extends the line between those two points to the Pathfinder site. At this point, they go to the cafeteria and trace the rover's path on a framed print of that area of the Martian surface. This puts the date at Sol 92 at the absolute earliest. We cut to Mindy Park and Vincent Kapoor, who very clearly states that Mark has been traveling for 13 days without changing course. When Mark is making the trip to retrieve Pathfinder, he departs no earlier than Sol 79. Without this, the astronaut will get 'the bends' due to nitrogen in the body tissues forming bubbles.

#THE MARTIAN SPACECONTROL PLUS#

The astronaut must pre-breathe pure oxygen to purge nitrogen from the body for this time, plus a period of 'vigorous exercise' at the start of each pre-breathing and decompression sequence. This gives the second problem - dropping from 12.5 or 14 PSI to 4.7 PSI pressure requires a progressive decompression sequence each time, which takes over two hours by the NASA protocol.

By comparison, the HAB pressure are shown as around 12.5 - 14 PSI with 21% oxygen, giving around 2.5 - 3 PSI oxygen, roughly 'earth atmosphere' range.

4.7 PSI is a standard for NASA, but at that pressure almost pure oxygen is used. That gives a 'Partial Pressure' for oxygen of only around one PSI, which is not sufficient to support life - the minimum for survival is around 2 PSI, with nearer 3 PSI to allow normal levels of exertion. There are two major problems with this: The suit value is around 4.7 PSI and 21% oxygen.

#THE MARTIAN SPACECONTROL CODE#

That code must be in hexadecimal.Īt various points in the movie, the 'head up display' of Watneys space suit is shown, giving environmental and suit data on the atmospheric pressure and oxygen content. ASCII (and alphabets generally) are not inherently linked to hexadecimal numbers however, without this NASA would not have been able to communicate the changes to the code of the rover. Even if Watney was insistent on using ASCII, he could have used decimal representations of ASCII (three-digit ASCII is only used for lowercase letters and characters he'd have no need of, so NASA could still represent any value with two characters), where he'd only need ten characters plus a question card and hence could have 33 degrees of separation instead of 23, increasing his disambiguation by 50%. NASA can see Watney's question card, so Watney could have written out an explanation to his base-6 code for NASA to follow. Watney could have made an alphabet with only six characters - NASA could represent 36 different values (all 26 letters and 10 digits) using two characters per value (same as ASCII), and Watney would maintain 51 degrees of separation between characters (including the question card) and thereby eliminate risk of ambiguity.

#THE MARTIAN SPACECONTROL FULL#

A scientist like Watney should have realized that the hexadecimal system he uses with Pathfinder is unnecessarily complex - Watney complained that using a full alphabet would give him only 13 degrees of separation between letters, but with sixteen hexadecimal characters (plus the question card he adds), there's only 21 degrees of separation between characters, and hence still a high risk of ambiguity.

The martian spacecontrol