How to land a man on the Mars and return him safely to the Earth
It looks like the main problem is NOT that we couldn't do it but that we maybe need more time and/or money for it?
I represent here a simple LEAMOR mission plan to Mars and back which just extends the Apollo missions and tries not to do anything more in the first phase than just to get a man on the Mars and return him safely to the Earth. LEAMOR stands for Light Extended Apollo Mars Orbit Rendezvous. (See also LOR).
The following picture shows the basic Mars mission phases.
|Typical Mars mission and its main events.|
All current missions use Low Earth Orbit (LEO) and Low Mars Orbit (LMO) as intermediate points for the mission. LEO is used to assemble the large spacecraft(s) that are required due to the long distance, long time of the voyage and relative large amounts of fuels (masses) required to complete the mission. LMO is required as the rendezvous point for the Mars lander (or vehicle).
Basically the LEAMOR Mars mission is exactly the same as the Apollo Moon missions except the spacecrafts have to be larger due to longer distances, stronger gravity and larger masses. Only chemical rockets are considered here .. but other options might be later available for the mission.
Here is the list of the main events during the mission:
- Several launches from the Earth to the LEO using SLS for example (usually 150 000 lbs and up to 300 000 lbs each)
- After the spacecrafts are bolted together in the LEO they will be Trans Mars Injected. This is the TMI burn which requires considerable amount of fuel and the first stage of the Entry Vehicle (EV) and the two cargo spacecrafts do that. Three different spacecrafts are sent for each manned mission. One robotic for RV (Return Vehicle), one robotic for MV (Mars Vehicle) and one manned EV (Entry Vehicle).
- After maybe some small mid course correction burns the spacecraft has to be slowed down to enter the Low Mars Orbit (LMO). This is the Mars Orbit Injection (MOI) burn and the spacecraft enters now the Mars parking orbit where it will usually wait other parts or astronauts from the Earth for the mission. All together 3 major parts will be sent to the LMO in a typical LEAMOR mission.
- When all required parts are in the LMO and the three astronauts have also arrived everything will be checked and the Mars landing with the Mars Vehicle (MV) can start. MV is similar to the Apollo Lunar Module (LM) except that it is larger due to stronger Mars gravity (it needs more fuel to slow to the Mars surface and to return from it). The first stay on Mars will most likely be not much more than a few days or maybe weeks in good condition.
- Since it is more safe to be in the spacecraft in the LMO parking orbit than on the Mars surface (very low temperatures, strong storms, etc) the astronauts will be taken back to the spacecrafts in the LMO
- When the orbits and conditions are suitable the Trans Earth Injection (TEI) will take place. The return part of the voyage uses nominally a different vehicle than the one with which the astronauts entered the LMO. This is now the Return Vehicle (RV). The Entry Vehicle (EV) will be left behind to the LMO with the cross tube and the Mars Vehicle's ascent stage which are no more required (for this mission).
- After maybe some mid course corrections the RV finally discards the Service Module (SM) and the Habitat Module (HM) parts and enters directly to the Earths atmosphere which will slow it down. A splashdown to the ocean as usual is followed.
This picture shows how it looks in the Mars orbit (LMO) when everything is ready for the Mars landing.
|LEAMOR in the Low Mars Orbit (LMO) ready for the manned Mars landing using the MV.|
The cross tube (in the middle) can connect up to maybe 4 spacecrafts and is used by the astronauts to enter the different sections of the combination.
- RV - Return Vehicle - Does the return part of the mission.
- EV - Entry Vehicle - Does the entry part of the mission.
- MV - Mars Vehicle - Does the Mars landing (2 stages: Descent and Ascent).
Different colors on the MV propellant tanks indicate different fuel types so that they are not mixed in the LEO assembly phase to each other. Usually two component propellants are used (for example Aerozine 50 fuel and N2O4 oxidizer). Only the main lower descent stage parts are bolted in the LEO since otherwise the MV would be too wide to be sent to the space through the Earth's atmosphere.
(More about the details in the next part of this artcle.)
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