I do not know much about it, but maybe some could clarify if it is possible to land the new Mars probe with a parachute. If we want to use a parachute, don’t we need the necessary air pressure for the parachute to work? The air pressure is only 0.6 that of the Earth, as shown below. If there is hardly any air pressure under the shut, the shut is ineffective.
Furthermore, the gravity is 62 per cent that of the Earth. This should help the entry, but the atmosphere is 95 per cent carbon. I see this as a layer of cement dust, or better coal dust over the planet. Since carbon is quite heavy, the entry vehicle could disintegrate, sort of like driving a car against a concrete wall.
I certainly can be on the wrong track, since I am no physicist, but maybe some is an expert on these matters.
The Martian atmosphere consists of carbon dioxide (95 per cent), nitrogen (2.7 per cent), argon (1.6 per cent), oxygen (0.2 per cent), and trace amounts of water vapour, carbon monoxide and noble gases. The average pressure at the surface is about 0.6 per cent of that on Earth and equal to the pressure at a height of 35km in the earth’s atmosphere. Surface temperatures vary greatly with time of day, season and latitude.
Maximum summer temperatures may reach 17 C, but average daily temperatures at the surface do not exceed -33 C. Owing to the thinness of the atmosphere, daily temperature variations of 100 C are common. Pole ward of about 50 degrees latitude, temperatures remain cold enough (less than - 23 C) throughout winter for the atmosphere’s major constituent, carbon dioxide, to freeze out into the white deposits that make up the polar caps (http://library.thinkquest.org/C0122083/info.htm).
The gravity on Mars is much lower than it is here on Earth, 62 per cent lower to be more precise. That means that Martian gravity is 38 per cent of Earth’s. A person weighing 100 kg here would tip the scales at 38 kg there.
Read more: http://www.universetoday.com/14859/gravity-on-mars/#ixzz22gXMgTbx.
Otto Sturhahn
Penticton