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Devon
Good catch, yeah there are a few mistakes in the conversation about pressure and you are absolutely correct - Rocky's idea of Earth's pressure is the 40% pressure he's seeing on the Hail Mary.
There's actually a larger error, when the beads were exchanged, they only compared the oxygen component of Earth air to the ammonia component of Eridian air. It's not clear how Grace jumps to the conclusion that the 1:29 is a pressure comparison and not simply a relative abundance comparison. Why didn't Rocky use strings of nitrogen beads for example? If Rocky had assumed nitrogen was the most imporatn gas, would Grace have incorrectly assumed that Eridian pressure was only 7x higher than the Hail Mary's?
If ammonia is the only component of the Eridian atmosphere, that comparison to Hail Mary air would mean Blip-A's pressure is only about 5.6x that of the Hail Mary and only 2.4x that of Earth.
I assume that the editors might have asked Andy Weir to simplify a more complex conversation about partial gas pressures for the readers' sake, and some of the information got confused.
There's actually a larger error, when the beads were exchanged, they only compared the oxygen component of Earth air to the ammonia component of Eridian air. It's not clear how Grace jumps to the conclusion that the 1:29 is a pressure comparison and not simply a relative abundance comparison. Why didn't Rocky use strings of nitrogen beads for example? If Rocky had assumed nitrogen was the most imporatn gas, would Grace have incorrectly assumed that Eridian pressure was only 7x higher than the Hail Mary's?
If ammonia is the only component of the Eridian atmosphere, that comparison to Hail Mary air would mean Blip-A's pressure is only about 5.6x that of the Hail Mary and only 2.4x that of Earth.
I assume that the editors might have asked Andy Weir to simplify a more complex conversation about partial gas pressures for the readers' sake, and some of the information got confused.
Bandar Julkiram
I have thought of that too. But I realized that Blip-A's internal pressure relative to Erid's sea level pressure was not mentioned in the book.* Andy Weir may have missed this or perhaps he only intended for Grace to make a point that Erid's atmosphere is thicker than Earth's to avoid the complication of details.
So Grace generalized the details to make a point either:
1. By implying that Erid's sea level pressure is 29 times that of Earth's mountain peak level pressure (which is also 40% of sea level pressure)
2. Or by assuming that Blip-A's internal pressure is also 40% of Erid's sea level pressure, making Erid's sea level pressure 29 times that of Earth's sea level pressure.
For the threaded beads or "necklace," Hail Mary only has one oxygen necklace. One may ask, where's the nitrogen necklace, given that Earth's air is 78% nitrogen? Since Hail Mary's atmospheric composition was not mentioned in the book, we can only guess by observation.* If the we assume Hail Mary's atmospheric composition is same as Earth, those Taumoebas that escaped the xenonite breeding tanks would not survive 78% nitrogen, given that the most resistant can only survive 8.25% nitrogen. Also, when Grace sterilized Hail Mary, he used Dubois's euthanasic nitrogen instead of tinkering the life support system to fill it with nitrogen. I think it is best to assume that:
1. Hail Mary's life support system was not designed to function with nitrogen.
2. Aside from carbon dioxide, Hail Mary's atmospheric composition is mostly or 100% oxygen with robust safetys in the electronics to avoid fires.
*Not mentioned? Or maybe I just missed it?
So Grace generalized the details to make a point either:
1. By implying that Erid's sea level pressure is 29 times that of Earth's mountain peak level pressure (which is also 40% of sea level pressure)
2. Or by assuming that Blip-A's internal pressure is also 40% of Erid's sea level pressure, making Erid's sea level pressure 29 times that of Earth's sea level pressure.
For the threaded beads or "necklace," Hail Mary only has one oxygen necklace. One may ask, where's the nitrogen necklace, given that Earth's air is 78% nitrogen? Since Hail Mary's atmospheric composition was not mentioned in the book, we can only guess by observation.* If the we assume Hail Mary's atmospheric composition is same as Earth, those Taumoebas that escaped the xenonite breeding tanks would not survive 78% nitrogen, given that the most resistant can only survive 8.25% nitrogen. Also, when Grace sterilized Hail Mary, he used Dubois's euthanasic nitrogen instead of tinkering the life support system to fill it with nitrogen. I think it is best to assume that:
1. Hail Mary's life support system was not designed to function with nitrogen.
2. Aside from carbon dioxide, Hail Mary's atmospheric composition is mostly or 100% oxygen with robust safetys in the electronics to avoid fires.
*Not mentioned? Or maybe I just missed it?
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