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63

There is a very nice Myth Busters video about bouncing a laser off the Moon linked below. To answer your question, current work is done with an array of corner cube reflectors on the Moon roughly 50 x 50 cm in size. Pulsed lasers on Earth have traditionally been green frequency-doubled infrared Nd:YAG lasers, similar to the "classic" DPSS green laser ...


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 ...


35

The University of Texas's McDonald Observatory performs laser measurements of the distance to the Moon using retroreflectors left by the Apollo astronauts. You can read all about it in the McDonald Laser Ranging page. Lots of technical details in this paper.


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 ...


19

A very similar experiment was performed, dropping a feather and a hammer on the moon. They weren't tied together, as Galileo's experiment was done, but it is similar enough that it is worth mentioning. From this YouTube Video


17

Seeds include a plant embryo with a root and a shoot already developed. When the seed germinates, the root and the shoot each elongate through tissue growth at the tip (meristem). Without environmental cues, the root and shoot will each continue to grow in the same general direction they had inside the seed. I emphasize "general" because the root or shoot ...


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

The Mariner 3 and 4 Mars flyby probes had angled vanes at the end of its solar panel arms which provided passive stabilization of the spacecraft from solar radiation pressure:


12

Space Studies Institute started by Gerald Oneil (Of Oneil colonies fame) has been pushing hard for a large centrifuge module in orbit somehow, somewhere. The point they make is that we know lots about 0G, lots of 1G and literally nothing about in between. I.e. To know the answer of how much gravity is needed to minimize changes, we need to experiment. ...


11

To be somewhat more specific than @geoff that gave an overview, regarding MOXIE (Mars OXygen In situ resource utilization Experiment), according to brief notice in the NASA press release that accompanied the Mars 2020 Rover scientific payload announcement: The Mars Oxygen ISRU Experiment (MOXIE), an exploration technology investigation that will produce ...


10

The ISS microgravity is generally considered to be of pretty poor quality, but the major cause of that is vibration from mechanical equipment and astronaut movement rather than atmospheric drag and reboosts (which are infrequent). For many experiments it's adequate, for others it is not - alternatives include drop tower tests and drag-free satellites such ...


10

Yes, the whole strut-and-lens system was a giant balloon. There is good information in this paper. Folded up and deflated, it looked like this. This fit into a box mounted on the side of the SPARTAN-201 carrier bus. The "balloon" was made of Mylar. The basic deployment scheme for IAE was based on ejecting the stowed reflector structure, as a package, ...


10

The drawing shows a Crookes Radiometer. They seem to spin nicely in even a little bit of sunlight. The common explanation is light pressure on the black vanes. Unfortunately, they don’t work that way. Photons bouncing off the white side transfer more momentum than ones absorbed by the black: of the mechanism was light pressure, they’d turn the other way. ...


9

Performing the experiment on the Moon would make it more accurate. The lack of atmosphere means there's no drag on the falling objects to interfere with the measurements. Galileo was smart/lucky enough to pick two balls which would minimize the effect of then very poorly understood drag. There was a small discrepancy due to drag when the two landed, but ...


9

Unfortunately my answer won't contain the crucial "yes" or "no" - for the simple reason that one hinges upon fine parameters and would likely require a good NASA study for actual answer. But the answer I can give without that currently is "Quite likely so." 1) matter of sustaining the blimp in void. That one's easy "yes". If the blimp's envelope rated ...


8

Looking at the information on what plants were taken in to space, it appears that the criteria include: Size: initially small plants were taken. This makes sense from a weight perspective Well studied: the list of plants aligns well with those studied extensively in universities. Again, this makes sense - it may be easier to identify odd growth in a well ...


8

If that were your only criteria, then you would lower the risk even further by not going at all. The goal is for each mission to have an acceptable risk and acceptable reward, to build crewed experience in deep space (i.e. to not have 30 years of uncrewed missions and one big bang at the end of that), and to have the overall developments fit within an ...


7

This is exactly what we call a solar sail. This works for orbit maintenance if the orbit isn't too low. If it's too low, the total impulse (force times time) lost to drag over one orbit is greater than the light-pressure (https://en.wikipedia.org/wiki/Radiation_pressure) impulse over one orbit, and the orbit still decays, just slower. Solar sails have the ...


6

It's important to note that the tortoises carried on the Zond flight were probably not given any food or water, and I suspect they were selected because they could survive that for a long period. So weight loss would be inevitable. (We know that Apollo 17 carried pocket mice in the Command Module to study radiation exposure, and that the species was chosen ...


6

I'm pretty sure this hasn't happened to Humans... Depends on your definition of 'exposed'... Soyuz 11 suffered an accidental depressuriation when preparing for reentry, when a valve accidentaly opened; the crew were not wearing spacesuits and had no protection against depressuriation. The cabin was in vacuum for around ten minutes before it reentered the ...


6

In 1964 and 1965 at Holloman Air Force base in New Mexico a number of chimpanzees were exposed to a vacuum for 30 seconds. They were at 2 mm of mercury, which is 0.038 psi. They were revived with pure oxygen. Their ability to perform tasks were tested after they suffered rapid and total decompression for that time. They all did OK. When Stanley Kubrick first ...


6

Neither mission made use of the dinosaur bone fragments in any of their recorded experiments. The most reasonable explanation is that the astronauts who carried them aboard did so for the opportunity to say "Dinosaurs in Space!" Sources: STS-51F Experiments - NASA STS-89 Mission Details - NASA


6

In simplest terms: You find a chemical that is made of a mixture of oxygen and anything else, and then cause the molecules of that chemical to give up their oxygen (and thus becoming something else). 2 H₂O can be cracked into 2 H₂ + O₂ by electrolysis CO₂ can be cracked into C + O₂ by highly inefficient electrolysis, or via photosynthesis. 2 CO₂ can be ...


6

There are many proposed chemical processes that can lead to taking elements found commmonly on Mars, and using them to make more useful things for humans. The entire process is vaguely know as In Situ Resource Utilization (ISRU) That Wikipedia link nicely summarizes some of the likely approaches to be taken. There was a great Sci Fi book that looked at ...


6

A scholarly article documented the student experiment involving fish was published in the journal Zoological Science by the Zoological Society of Japan and summarizes the set-up and results of the experiment. Apparently there were no goldfish on-board from a student experiment; these were Medaka fish fry. There is no mention in the abstract if the results ...


6

could a satellite have a stiff sail like the white side to let light pass and like the black side capture light to provide enough force to keep it in orbit? Not really. Let's ignore the point Crooke's Radiometer works on different principles. Yes, you can use solar pressure to give your craft acceleration, and yes, changing the surface color will vary ...


5

The failure you're referring to occurred in December 2013, Expedition 38. According to the Mission Updates: With the valve no longer closing, Loop A (of the External Thermal Control System) lost all of its thermal control capability. As a result, thermal loads on that channel had to be reconfigured to protect ISS systems. The Internal Cooling System ...


5

Re Quora Fean's comment I imagine the OP means to have a fixed lab at a convenient location, and a smaller rover collecting samples and bringing them to this lab. That's similar to how the 1997 Mars Pathfinder mission worked. The Sojourner rover didn't have a robotic arm. It also didn't have the ability to communicate with the Earth. That was the base ...


5

In 1996 in a vacuum chamber space suit test Jim le Blanc had his air hose detach and he was exposed to a virtual vacuum at 0.1 psi. It was 87 seconds before the chamber was returned to normal air pressure. The supervising engineer Cliff Hess said “Essentially, he had no pressure on the outside of his body and that’s a very unusual case to get,” He passed out ...


5

I think they had an issue with the methane sensor. From India's Mars Orbiter Mission Has a Methane Problem: The problem has to do with how the instrument collects and processes detections of methane in the atmosphere, a technique known as spectroscopy. "Imagine that you hold your hand in front of you and extend your four fingers ... Suppose that ...


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