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You have to calculate the deltaV that these thrusters can provide you. You can do this by using the Rocket Equation. You need the ISP value of those thrusters and the starting and final mass of your cubesat (i.e. mass when you are deployed in LEO and mass after you have expended all your Xenon). That will give you the maximum available deltaV. This needs to ...


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NASA [1] indicates that helium-3 can be assessed indirectly by measuring the presence of titanium dioxide and soil characteristics ("maturity"), the correlation having been derived from the study of Apollo lunar rock samples. The helium-3 is "detected" through remote analysis for these favorable mineral and soil characteristics. Using data on the titanium ...


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I grabbed a couple pix from SkyAndTelescope which may help. On a macro scale, you can see that the path is chosen to avoid craters and whatnot: This next one is a better version of what you posted, and again it looks like the tracks are avoiding various craters or small dips in the landscape:


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These images are taken during local night. i.e. LRO is flying over an area of the moon which is not illuminated by the sun at that time. An easy way to confirm this is to click on the "info" icon next to the image in USGS Pilot, and look at the "local solar time" field. If the time is between about 06:00 (6am) and 18:00 (6pm), you will see a dark image or a ...


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A numerical integration is the best option for me. Using the JPL’s DE/LE438 ephemerides and the NAIF’s SPICE library, I found the dates when the angle between the Earth-Sun and the Earth-Moon vectors is about 180, 0 and 90 degrees and the Moon/Earth distance is about the same: Date Angle Distance 2000-11-12 175.54 371281 2008-03-08 4.25 ...


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This is a supplementary answer with calculations (for 1) two bodies and 2) three bodies) problem which confirms that @MatthewWells answer is correct. Would the Moon hit the Earth or not? Yes, it would hit the Earth. Do we have to do detailed numerical integration to find the answer, or can we use some simple equations that involve energy and/or ...


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This is easier than it sounds, provided we choose a suitable reference frame. In this case, we'll to consider the problem from the (doomed) perspective of someone standing on Earth's surface directly below the Moon. Since the question specifies that relative velocity between the bodies is zero, we can construct a free-body diagram, treating the gravity of ...


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Fast particles, which radiate energy from Moon, are not stopped by any atmosphere. So Moon is general is colder than Earth, just like Venus/Mercury. Due to additional atmospheric isolation, Venus is hotter, though Mercury is closer to Sun.


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Because while the lunar surface is being heated, some of that heat is conducted away from it into a large heat sink, the moon. Isolated atoms in the thermosphere lack such a heat sink. (Both the lunar surface and the thermosphere are significantly colder "at night" when shaded from the sun, by the moon and the earth respectively.)


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Now that's it's been a few months... according to Lok Sabha (a representative of the Indian Department of Space): During the second phase of descent, the reduction in velocity was more than the designated value. Due to this deviation, the initial conditions at the start of the fine braking phase were beyond the designated parameters. As a result, Vikram ...


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