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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

Using Spice data files, the Skyfield library for Python can now report lunar libration as the sub-longitude and sub-latitude of the point on the Moon facing the Earth. To take an example from its documentation: from skyfield.api import PlanetaryConstants, load ts = load.timescale(builtin=True) t = ts.utc(2019, 12, 20, 11, 5) eph = load('de421.bsp') earth, ...


-2

Because NASA's SLS will be primarily used for manned Moon and asteroid missions (as well as an unmanned spacecraft to Jupiter) while SpaceX's BFR/Starship is to be used for a touristic circumlunar mission (without orbit insertion or landing on the Moon and thus carrying no lunar lander) and for manned Mars missions. Later on, NASA's SLS is to be used for ...


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For a more casual answer to this question--The Mythbusters built a replica of the lunar flag assembly. In a vacuum chamber they moved it around to see how the flag behaved in a vacuum. Dailymotion video Time index 11:30


3

I agree with Ingolifs' answer; you can create a porkchop plot for a transfer between any two orbits. For an Earth-Moon porkchop you could pick either a point on the Earth's surface or a particular low Earth orbit as your start. For example, here's a porkchop plot showing the delta-v required for transfer from Apollo 13's initial Earth orbit to the Moon (...


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On Earth, before a mineral or petroleum resource is mined/extracted, the deposit is delineated and evaluated. Briefly, the process involves sending a some geologists and some drill rigs and their operators to a deposit and drilling holes through the deposit on a predetermined grid pattern. The drill cuttings or core (depending on the type of drill used) ...


2

Even though the question has already been mostly answered, here is more information about current Lunar Ranging activities. The EUROLAS Data Center (EDC) of the Deutsches Geodätisches Forschungsinstitut at Technische Universität München has a nice website with an API to find laser ranging data. The data are the same than on the CDDIS website as the data ...


3

There is a nice Wikipedia image of Earth (ø = 12,756 km) and Moon (ø = 3,476 km) at the same scale. When you look up to the full Moon at night with a clear sky you are able to see many details. The astronauts looked up to the much bigger Earth at the same distance. So they were able to see much more details of Earth than we see of the Moon.


2

Possible answer: Another answer not yet explicitly listed could be: to limit the loss of-/build/maintain/expand their independence on other parties when it comes to launch technology (usage). For example, an agency might account for uncertainties in the availability of the technology provided by other parties, or contracts might be such that it becomes ...


6

Yes, according to Mike Collins (but from lunar orbit, not on the surface). The earth as seen from this distance - nearly a quarter of a million miles - is an unforgettable sight. To begin with, it looks tiny, the size of your thumbnail held at arm's length. It is mostly ocean and clouds, the blue and white dominating the brownish-green of ...


5

I don't know if any Apollo astronaut talked about it, but in the famous "Earthrise" photo taken from lunar orbit on Apollo 8, landmass (the west coast of Africa, I believe, at the lower edge of the sunlit portion of Earth) is distinguishable from the oceans:


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SLS has been in development for a long time, although it suffers from political winds quite a bit. It started in its current form in 2011, when there was no other system in existence that even was close. Falcon Heavy was a concept then, but it would have only been slightly better than Delta IV Heavy, still nothing compared to SLS. They considered other ...


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Because there are no super heavy-lift launch vehicles flying right now. In fact, simply by existing, SLS will be the most up-to-date and the most efficient super heavy-lift launch vehicle since the Saturn V (Shuttle is debatable). Super heavy-lift launch vehicle, Proposed designs When looking at current SpaceX rockets, the Falcon Heavy are human certified. ...


34

In the defense of NASA, SpaceX does not per se have an operational vehicle for the purposes they want to use SLS. (Yet, Starship is coming) However, missions to the moon using Falcon Heavy vehicles have been proposed by Bob Zubrin. Once SpaceX has an actual flying Starship/Super Heavy I think the situation will change. Ultimately the SLS program is ...


28

So let's break down the answer into bite sized chunks... How do you transfer a spacecraft from one solar system body to another? There are two main things you need to do. Set up an orbit that intercepts the orbit of your target planet/moon. Time it so that your spacecraft intercepts the target orbit at the same time as the planet/moon you're trying to ...


19

Does pork-chop plots exist for Earth-Moon System? No, because the concept doesn't make much sense. The Earth-Mars configuration and Mars' eccentricity makes the cost to send a vehicle from Earth to Mars vary by a huge amount. Pork chop plots are a useful way to visualize these huge variations. The cost of sending a vehicle to the Moon on the other hand ...


0

In space missions, it is common to have two pilots. The "commander" is the more senior one, and does most of the piloting, while the "pilot" is the junior one, and may have some roles. Neil Armstrong, as commander, was the more senior pilot, and practiced the landing. Buzz, on the other hand, was primarily tasked to manage the spacecraft when on orbit, ...


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While the modules were launched with the engine in between, the modules docked nose-to-nose. The crew moved between the modules using hatches in the noses of each module. Image location Related questions about the "transposition, docking, and extraction" maneuver: Reasons behind the "Transposition, docking and extraction" maneuver Did the ...


4

The polar regions aren't filled with useless texture - it just isn't very accurate. I have done the exercise you are going through. I'm pretty sure that data package is the best that exists, and better data won't be coming along any time soon. Here's what I did. I adjusted the top and bottom of the map to better match the rest. Yeah, that's just fudging. ...


1

You may be able to get much further out. It depends on exactly what you mean by "GPS" and how soon you need it. There is a mission on the International Space Station right now that is working on a new GPS. In this case, the "G" stands for Galactic! The mission, NICER, is primarily intended to study neutron stars. However, as stated in Ref 1, "... in ...


7

GPS is since a few years used by satellites in geostationary orbit. Check out for instance this paper by Lockheed Martin about GOES-R, from the ESA GNC 2017 proceedings: https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20170004849.pdf


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