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199

To be honest, I don't know how to measure atmospheric pressure, so I cannot discriminate on that basis. Initially my answer only included unmanned missions, but based on suggestions I've decided to add the Apollo missions as well. Moon The first landers performed intentionally hard landings and did not get pictures from the surface. I want to include them ...


52

Chandrayaan-1 hit the Moon at high speed and did not survive its "landing", which would have been much more difficult to engineer. (Its successor, Chandrayaan-2, which will actually land, is expected to cost \$125 million and has taken more than ten years so far, as opposed to the three years for Chandrayaan-1.) As far as cost goes, besides India's own (...


47

To first answer the question ad litteram, NASA has so far successfully landed four stationary labs on Mars (Mars landing dates in parentheses): Viking Lander 1 (July 20, 1976), Viking Lander 2 (September 3, 1976), Mars Pathfinder (July 4, 1997) and Phoenix Mars Lander (May 25, 2008). Here are their landing sites on a map of Mars generated with Mars ...


46

Preface: I am far, far from an expert in space electronics; I don't think I can weigh in on how much these sensors actually are, which is the title question; all I can offer is an uneducated inane ramble on where that money might be going. Let's take your analogy of a bargain-basement thermal sensor; actually, let's specify a common off the shelf Melexis ...


39

In July 2005, the Deep Impact mission released an impactor that excavated a crater, estimated to be 100 meters wide and 30 meters deep, into comet Tempel 1.


27

I'll chime in with the other two well-stated answers. In addition to all the testing, there is the issue of "What do you do when the instrument fails a test?" Most COTS (Commercial Off-The-Shelf) instruments you might get at Home Depot or even Omega Engineering are designed to work in an Earth environment, with some margin. But not too much margin; that ...


26

I'm pretty sure that by "soft good" he means it's an element of the system that can't be completely constrained from a simulation or engineering standpoint, in this case fabric. If you're working with static systems or systems with a limited amount of degrees of freedom, it's possible to calculate and analyse every possible state the system can be in. For ...


25

In order for a combustion process to happen, you do not only need fuel, you also need an oxidizer. On Earth, that is usually the oxygen in the air. In Titan's atmosphere, there is no oxygen. This applies to other atmospheres too, like the hydrogen dominated atmospheres of Jupiter and Saturn. Hydrogen, just like the methane in Titan's atmosphere, is flammable ...


22

Thanks to @MarkAddler for his search suggestions I've tried to balance length against completeness, and both lost here. However I have included enough material to try to be convincing that RTGs, singe-use storage batteries, and rechargable batteries for higher power events have all been investigated and solutions exist to provide at least the electrical ...


21

Feel free to edit this answer to add more or adjust formatting. List may be incomplete. Ordered by launch date: Hayabusa 2 and MASCOT to 162173 Ryugu, Japan/Germany/France, launched 2014, landed four rovers in 2018, currently surveying, Hayabusa 2 will depart December 2019 and return to Earth December 2020 OSIRIS-REx to 101955 Bennu, USA, launched 2016, ...


21

Looking through the images on the Apollo Archive, which I believe to contain all publicly available images and checking the ones at the end of EVAs I was not really able to find anything satisfactory. The best ones were before lunar takeoff of Apollo 17 None of them directly shows the floor however. The second one shows a little compartment for the helmets. ...


20

In the 1970s, NASA sent two Viking probes to Mars. Is this the 'unmovable lab' you're looking for? The drawback of a stationary lander is that it can only gather data on one location. When you have finished analyzing that location, the mission is over. A rover, on the other hand, can gather data in different locations. Its mission can last as long as the ...


20

Reasons not to provide mechanical means to clean solar panels on Mars: and this is the primary reason: Wind on Mars occasionally blows the dust away. This means dust is not a major issue, but a minor one. Spirit and Opportunity functioned for years despite not having dust removal equipment. Mechanical operations are expensive: you've just added a series ...


18

A one-way trip is much simpler and much cheaper than a return mission. a return mission is more complicated because it has to do more a return mission is much heavier (because of the extra systems, and the fuel needed for the return capsule) which means it needs a bigger launcher which is more expensive We have had no sample return missions from any ...


16

The harpoons are intended to hold the lander to the surface long enough to get the ice screws on the lander's legs in securely. The ice screws are intended as the more permanent hold-down solution. Bear in mind that the comet offers essentially no gravity; imagine trying to drive a wood screw into the ceiling without pushing the screwdriver upward at all. ...


16

According to Wikipedia launch windows to Venus occur every 19 months. In some cases multiple successful probes were launched with the same design at the same time so I'll group those together (the Soviets launched two similar/identical missions per launch window they actually used to ensure mission success through redundancy). I'll label each mission with ...


16

The simple answer is that taken as a whole the Venera missions didn't land particularly close together. Starting with Venera 4: The overall spread of Venera landing sites (when you include the probes that didn't survive to the surface) is nearly 110° of longitude. For comparison, the spread of Luna landing sides on the map you provided of the moon is ...


15

The Opportunity, Spirit (RIP), and Curiosity rovers all have high-gain antennas that point at Earth when in use, using a two-axis gimbal. They are used mostly to receive the command loads every sol from Earth. The rovers also have low-gain UHF antennas, basically like a car antenna but shorter, for communicating with relay orbiters around Mars. That path ...


15

The short answer is that it's easier to build a rover with all the lab-stuff on it. Reuse of things in-space is harder than one might think. If there was one re-usable lab, it would need to be re-stocked, repaired, etc. Different rovers would need to be 'compatible' with the existing lab, hampering new development. Not only that, but the rovers would ...


14

Let me just expand a bit on @Tildalwave's answer. Most landers on airless bodies need a propulsion system, because they will be going too fast otherwise to land. But that's only because most landings have been done on objects with a lot of gravitational mass. Let's just try and figure out what the escape velocity would be. Wikipedia gives us the following ...


14

Initially it looked like there was life, then that was dashed, but newer research might be indicative of life after all. From http://csep10.phys.utk.edu/astr161/lect/mars/viking.html, back in 1976 we had: The 4 basic experiments that the Vikings carried out to search for evidence of life were: Gas Metabolism: look for changes in the atmosphere ...


13

The minimum $\Delta V$ is effectively a Hohmann transfer. You would de-orbit just enough to barely touch the surface at periapsis, and right at the surface you would do an instantaneous impulsive burn (also known as a "suicide burn") to exactly cancel your velocity relative to the surface. Done! A perfect landing. In the real world however you don't have ...


13

How exactly did the floor of an Apollo Lunar Module look like after EVA(s) during an actual Apollo mission (before or during launch from the Lunar surface into Lunar orbit)? Besides, by any chance, how did the hatch and its sealing look like? I'd figure all of it was all pretty dusty ... I am looking for at least one actual photo! First to show floor ...


12

Yes, by quite a bit. Right now the heaviest object soft landed on Mars is Curiosity, as you noted. The mass of it is 900 kg. The Red Dragon is 6400 kg, plus payload of up to 2000 kg (Maybe more for later flights) In fact, when successful, the Dragon will be more than the sum of every other object which attempted to soft landed on Mars. Each Viking massed ...


11

Hellas basin is certainly an interesting region, and several landing site selection processes evaluated candidate sites in it, mostly in the Northernmost region that's above the 30° South circle of latitude:      All Mars candidate landing sites that were considered for all NASA missions up to Mars 2020 Rover. Source: 1st Mars &...


11

An RTG certainly can and would work on Venus, since the hot side is about 1200 C. It just wouldn't be as efficient as it would be with a colder cold side. Search for papers by Geoff Landis on this.


10

Surveyor Program landers (1-7) made robotic soft-landing on the lunar surface. The major difference between Surveyor landers and Chang'e 3 is that they didn't orbit the Moon, but were put on a ballistic trajectory and the autopilot computer did the rest. NASA page on Surveyor 1 puts the soft-landing procedure like this: For the landing sequence, an ...


10

Since the question is about terrestrial bodies, maybe the Deep Space 2 mission penetrating about 0.6 m (or 2 ft) into Mars was the deepest. At least that's what it was designed for, but we don't know if it reached that depth.


10

Just to give you an idea, here is how the cost might break down. The COTS version will need to be torn apart to survive vibration testing, along with added material. It will need to have some kind of software written to send the data to the spacecraft. Some testing will need to be done to see if the instrument will work on Mars. The thermal issue will ...


9

You need to divide between heavy bodies with a significant field of gravity and light bodies, around which you can experience microgravity (also called µg-environment) only. On the surface of the Moon, you can experience about 0.17 g. This looks like a small number, but it is still fairly sufficient for a 'normal landing'. In the case of asteroids and ...


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