194

This is the Apollo 11 photo designated AS11-40-5925, a popular shot with moon landing deniers. The camera is facing generally north-north-west. The sun is low in the sky, about 10º-15º above the horizon on the east. The silver pole in the upper right of the photograph is pretty much straight up, casting shadow in the expected direction. The landing leg in ...


168

(A) who (if anyone) was the first human to actually be asleep (that is to say, presumably inside the lander) - not just a scheduled sleep time - on the Moon? It depends on your definition of sleep. Maybe Buzz Aldrin, curled on the floor of the LM cabin: The best Aldrin managed was a “couple hours of mentally fitful drowsing.” Armstrong simply stayed ...


163

The photo (frame 3021) appears to have been taken from an approximate altitude of 1180 KM, on the return journey to Earth. We infer it was taken on the return journey as frame 3005 was taken after trans-Earth injection. And, presumably, by "Revolution: TE" in the image's information. The image information tells us the photo was taken by the Metric/Mapping ...


156

Fun question! Provided the three Lunar Roving Vehicles (LRV) left on the surface of the Moon by the last three Apollo program missions were not, tongue-in-cheek, towed away for unpaid parking, reckless driving and littering fines, or clamped by the Lunar people (not to be confused with Lunatics), I don't see why not, provided you have brought along all the ...


126

I believe it was John Young, during an Apollo 16 EVA fell to the lunar surface. Though awkward, he got up unassisted by attempting a series of what looks like push-ups until he was able to get himself to his knees. Then he had little difficulty standing up from resting on his knees. This YouTube clip shows how he did it. Apollo 16 astronaut falls and ...


125

As you said, it varies. Imagine I'm in Chicago and you're in London. My little dog is running circles around me. Which is closer to you, me or my dog? While the correct answer is "it depends on where the dog is in its orbit around me", I'd argue that a better answer is "it doesn't matter" - the distance between you and me is so great that any little ...


106

NVIDIA rendered Aldrin descending to the surface and discovered that, just as the conspiracies claimed, it couldn't be reproduced with direct light from the sun as the sole light source. Of course, as in photos on Earth, indirect light (reflected, scattered...) is an important source of scene illumination and must be taken into account. After adding the ...


106

Traveling from Mars's surface to Earth's surface requires less energy than traveling from Mars's surface to Luna's surface, but traveling from Luna's surface to Mars's surface requires much less energy than traveling from Earth's surface to Mars's surface. For the purposes of space-travel, the actual physical distance is much less important than the ...


100

Probably, but you likely wouldn't drive it away. Not only will the batteries be completely discharged, but the rovers have gone through a large number of lunar days since then, creating a large thermal cycle. The number of thermal cycles is on the order of 500 for each one, and the cycles are brutal, going from -150C to as high as 120C each time. Even ...


100

During the Pathfinder landing the airbag system hit the ground at about 20m/s. This seems fast but compared to other space speeds, it's very slow. When the pathfinder rover arrived to land at Mars, it was cruising at around 7300m/s. To get this velocity to zero, the parachutes, heat-shield, and single-fire rocket engine did their work to kill the velocity ...


90

Does the US have some secret insight into landing on the moon? Yes: fail early and often. The US developed experience with uncrewed landings first, before attempting crewed landings in the Apollo program; those earlier programs had a very high failure rate. The first US lunar spacecraft were in the Ranger program, which was simply attempting to hit the moon ...


84

At the moment, there are a few groups trying to reach Mars, and a few groups who are trying to reach the Moon. Mars One has grabbed headlines lately, SpaceX states Mars colonization as its long term goal, and there are numerous smaller groups. For the Moon, there is the Google Lunar X prize, Shackleton Energy Corp, and OpenLuna, and again numerous other ...


79

Distances to Mars You can answer the question with Astropy, a Python library for astronomy. Here's a diagram of distances from Earth to Mars and Moon to Mars, between 2000 and 2030. You can see that the two curves are so close from each other that they look like one single curve. Here's a zoom around the last opposition, in May 2016: Relative difference ...


77

The Apollo spacecraft consists of three major parts: The Command Module (CM), a conical module where the three crew members live during launch from Earth and travel to and from the moon, and which re-enters Earth's atmosphere alone at the end of the trip; The Service Module (SM), a cylindrical section containing fuel, power, life support, communications, a ...


72

Apollo 11 mission had two modules Lunar module - which descent to moon carrying two astronauts command / service module- CSM was designed to return astronauts from the lunar surface on a direct-descent mission to earth and splash down. Direct telecast from the Command service module is not possible but CSM stored the recording of conversation which is ...


71

No. Planting a flag was the idea of NASA's "Mr. Fix-It", Jack Kinzler, less than 4 months before Apollo 11's launch: Kinzler believed that the people of the United States would also want to see an American flag to commemorate the enormous achievement of landing a man on the surface of the moon. The original LM design had an American flag painted on the ...


67

Right now, almost 100% of existing research on growth in gravity fields is basically at 0g (ISS/Mir/Skylab/whatever) or 1g. There are a lot of questions of what happens at 1/6g or 2/3g? No good experiments to demonstrate. Thus the Chinese lander is testing 1/6th g. SpaceX is likely to brute force test 38% g when they get to Mars. It is entirely possible ...


66

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 ...


66

Oh, I can answer this one. In my structural geology class, we breezed over a few paragraphs on the tectonics of impact craters, but it was in the textbook, and, being space-related, I was intrigued. One note: while most of the papers you'll find are on our own geology, the moon isn't that different compositionally from Earth at all, so I'm assuming the ...


64

The Neil Armstrong's "First step on the Moon" was filmed by a camera installed on the MESA (Modularized Equipment Stowage Assembly) at the side of the Apollo Lunar Module (LM) descent stage that Neil Armstrong had to pull a lanyard to unlock the pallet and make it drop open. A switch inside the LM, operated by Buzz Aldrin, then activated the TV camera which ...


64

Although the temperature at altitude can be several thousands of degrees, the atmosphere is so thin it does not transfer heat efficiently. Wikipedia explains it very well - The highly diluted gas in this layer can reach 2,500 °C (4,530 °F) during the day. Even though the temperature is so high, one would not feel warm in the thermosphere, because it is ...


64

This discovery is news because the water found is in a sunlit area, the Clavius Crater. Previous water discoveries were all in 'cold traps', which are areas where sunlight cannot reach, so water resources on the moon for colonies or space exploration was thought to have been limited to permanently shaded areas - the rest was thought to have been boiled off ...


62

Going directly to the Moon would require a very small launch window. The Earth orbit before enabled a launch window of about 3 to 4 hours, see this question. Abort from an Earth orbit was possible when the second ignition of the third stage of the Saturn V failed using the Service Module engine to initiate a reentry. Time in orbit was used to complete the ...


61

A big difference is that you wouldn't need to leave someone in lunar orbit. We now have experience and confidence in the remote operation of an uncrewed vehicle. So you could have a crew of two instead of three. Or perhaps a crew of three to the surface with a larger LM. Overall, there would be much more automation, especially for the landing process, ...


56

As always, the Apollo Lunar Surface Journal is a treasure trove of annotated examples. During the later (J) missions in particular, Ed Fendell, remotely operating the rover's TV camera, managed to capture a few for posterity. Falling forward (straight or a bit to one side) happened to several moon walkers, and getting up was not that difficult. Only Charlie ...


54

Two main reasons really: The dust on the Moon, while it would be extremely fine-grain, is also highly charged due to Sun's radiation and solar winds, so it would stick quite good to the surface, grain to grain, but also cling to astronauts' space suits, something that was made quite apparent when they had fairly big problems getting it off and somewhat ...


53

The process was a great deal more sophisticated than pointing and thrusting, and the CSM was cooking along at over 1600 m/s, circling the moon every 2 hours. Mission control, however, had fairly precise tracking of the positions of both the CSM and the landing site, and they computed the correct time of launch to begin the rendezvous using powerful Earth-...


53

How to Protect and Preserve the Historic and Scientific Value of U.S. Government Lunar Artifacts summarizes the 1967 Outer Space Treaty thusly: These recommendations are consistent with international law, including the following: The 1967 U.N. Outer Space Treaty (OST), which provides, in part: That outer space shall be free for exploration and use by all ...


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 (...


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