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14

Taking Mars Pathfinder and Viking 1 as examples: Mars Pathfinder was a direct entry at 7600 m/s and removed about 0.7-0.8% of that propulsively. Parachute deployment was at 360-450 m/s, and landing rocket ignition at 52-64 m/s which slowed the vehicle to 0-25 m/s before cutting the bridle: https://mars.nasa.gov/MPF/mpf/edl/edl1.html Viking 1 landed from ...


12

Let's talk about the major materials that made up the Venera landers. https://space.stackexchange.com/a/9965/25 has a great summary of what the landers were made of, they are composed of include Titanium, gold, fiberglass, KG-25 an high-temperature polyurethane foam, and PTKV-260. There are a bunch of other materials, likely including some glass and other ...


10

There will likely be significant differences in the required tankage, if nothing else. The paper Lunar Lander Conceptual Design shows a comparison between landers with similar payload requirements and different engine systems. Note the different in tankage and propellant weights for the two options.


9

NASA has helpfully provided a list of spacecraft classifications which covers these terms (and more.) Rover: a vehicle. There have been 4 rovers on Mars: Sojourner, Spirit, Opportunity and Curiosity. Lander: any spacecraft that can land safely. Lander spacecraft are designed to reach the surface of a planet and survive long enough to telemeter data ...


8

According to Quanzhi Ye (via tweet; while not a primary source, he is planetary scientist who understands Chinese) it is for simulating Mars' lower gravity while testing obstacle avoidance for the Chinese Martian landers. There is some additional information on the testing program for the lander and Long March 5 rocket, which will carry it to Mars, in this ...


7

A lander with storable propellants needs to keep them at close to room temperature, for a minimum of several days. A hydrolox system will take up much more volume due to the low density of LH2, and that big LH2 tank has to be kept at around 20 K. You are going to need a major structural redesign just to deal with the greater volume of the liquid hydrogen ...


4

Answering the "what would work?" part of the question: I would use an electret haired brush which barely touches the surface of the solar panels. Electret filters are very effective in collecting fine particles. The brush is mounted on a simple wiper. Once it collected the brown powder it vibrates downstream to shed the dust of, a bit like a dog ...


4

The polar ice caps of Mars are more challenging for a number of reasons. Mars has a similar tilt to Earth, which means that the polar regions have some of the same problems. The two main problems are extreme cold and very long nights over the winters. These together mean that there is a limited time when such missions could take place. For the last 20 years,...


3

Apart from the mechanical aspects of tankage, ullage, ignition, and the like, there's a significant safety issue. Unless you're starting a Moon colony, the "and return them safely to Earth" bit is pretty important. Hypergolic engines can be made extremely simple and reliable -- the Apollo LM ascent engine was basically a pair of valves, a combustion ...


3

To begin with, SpaceX bid Starship as their lunar lander. Starship used methalox as their propellant for their Raptor engines. However, Starship does need landing engines higher up on the hull for the moon landing to avoid digging a crater in the moon surface with the Raptor exhaust. So why don't they use SuperDracos here? Well, SuperDracos uses as ...


3

Partial answer: From this ESA-provided diagram (source), and corroborated by everything I've run across: It's certain that NASA will be building both the lander & ascent vehicle. But we already knew that--who exactly will be building it? Most of the papers I've read regarding the MAV design specifically are authored out of Huntsville, so it seems likely ...


3

There is a lot in development to meet the 2024 Human Lunar return goal set by the National Space Council. At IAC this year, Blue Origin unveiled their national team consisting of themselves, Lockheed Martin, Northrop Grumman, and Draper Labs. This team will collaboratively build a Lunar Lander and submitted to NASA's design request on November 5th. Their ...


2

The JAXA document Candidates for landing sites for the Hayabusa2 mission explains in detail how landing sites were selected for Hayabusa2, MASCOT, and MINERVA-II1. (MINERVA-II was a two-part project consisting of MINERVA-II1 and MINERVA-II2; this document probably omits MINERVA-II2 because it was an optional payload and wasn't scheduled for release until the ...


2

First of all, the SuperDracos were designed from the start primarily as a launch escape system. Although using them for propulsive landing was explored extensively, it was never implemented. For landing on Earth or Mars, the atmosphere is used to lose most of the craft's speed, with the thrusters (and/or parachute) used only after that. The moon has no ...


1

Note that you're mixing up the lander's "retro-rockets" and the special motors fitted for the tests. The special motors are different from the retro-rockets used by the real landers to touch down on Mars. They were "boost motors" provided solely to put the test vehicle in the proper altitude and speed conditions for the parachute deployment tests. The BLDT ...


1

ok so with a quick search since mars gets 44% of the light on earth. so with some math we get about 1.5 lx but wait, mars's atmosphere is different than earth's we can assume mars's twilight is around 1 lx or at least less than 1.5 lx. Now keep in mind this is using civil twilight measurements. This is as far as I can go to answering but I think it's safe to ...


1

The image above is an enlarged part of a HiRiSE image captured in Januari 2012, and the only other one that I could find.


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