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261

Since the Apollo 11 code is on GitHub, I was able to find the code that looks like an implementation of sine and cosine functions: see here for the command module and here for the lunar lander (it looks like it is the same code). For convenience, here is a copy of the code: # Page 1102 BLOCK 02 # SINGLE PRECISION SINE AND COSINE ...


92

This is a very broad question, but I'll take a stab at it. It was understood that gravity pulled the Earth into a spherical shape, with dense solids and liquids below less-dense gases, and it was expected as early as the 17th century that the atmosphere would get steadily thinner with increasing altitude, giving way to vacuum. These expectations were ...


74

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 ...


74

Laika's magical mystery propellant was kerosene and LOX. Sputnik 2 was launched on the 8K71PS launcher. This was a modified R-7 ICBM, and like all the R-7 derived launchers, its RD-107 and RD-108 engines burned kerosene/LOX. The Russian specification for rocket-grade kerosene is called RG-1, and it's similar to the American RP-1. The specific impulse of ...


63

One important note is that rocketry predates space travel - by a lot. The V-2 rocket christened "MW 18014", the very first suborbital flight, (meaning the rocket flew to space, but didn't go fast enough to orbit the earth, so came back down) was in 1944. This rocket was designed to launch, fly in a specific trajectory, and land in a (relatively) specific ...


58

They are burns, with the direction of the arrow roughly indicating the direction of thrust. Ascent Earth orbit insertion Trans-lunar injection Midcourse correction Lunar orbit insertion Burn to drop out of lunar orbit for landing (LM) Ascent from lunar surface (LM) Lunar orbit insertion (LM) Trans-Earth injection Midcourse correction Whew! Found a ...


56

The reason is delta-v, which is a crucial concept in Spaceflight. It means change in velocity, and is the primary 'currency' that space mission have to expend in order to reach places in the solar system. On earth, if you want to go anywhere, you can get there at any speed, it just takes longer. Unfortunately, that is not how it works in space, because the ...


56

Supplementary answer: Some of the confusion arises because there is also a geographic feature named Cape Canaveral. It's pretty much the green area shown in the other answer, east of the Banana River. On this geographic feature Cape Canaveral is built Cape Canaveral Air Force Station. Today's Kennedy Space Center (KSC) is built on Merritt Island. Even ...


46

So far as I can tell, it was first a saying used by military personnel as the phrase "Rapid Unintentional Disassembly", for a phrase when a gun broke apart if you misused it. This was used by a book for Navy Personel in 1970, so I suspect it was in use for a while before then. This seems to have evolved from that phrase somewhat over the years. The earliest ...


46

Seeing as the answer is "no" (As per @DarkDust), I thought I'd add a situation that's similar. There was a short period aboard Mir after the collision with progress where all astronauts were without power, life support, lights and communication. The cosmonauts were interviewed about it and said something along the lines of "after being in here for so long ...


44

No; the first full views of Earth from high-altitude satellites predate Apollo 8 by at least two years. This web page has a nice progression of pictures of Earth from space from 1959 on. A Soviet satellite (possibly Molniya-1-3) took this crude picture on May 30, 1966: DODGE took this picture in September of 1967; this is believed to be the first full-...


43

The Mars Society has a good indication of what the most serious medical issues have been in space flight. These include: A number of cases where the gloves leaked in an EVA. (STS-37, Mir Space Station) The STS-37 was possibly the most serious, only the fact that the astronaut was also bleeding kept this from a much more serious issue, similar to how Mark ...


41

From Wikipedia's article on Vostok 1: Path of Gagarin's complete orbit; the landing point is west of the takeoff point because of the eastward rotation of the Earth. The flight was at least one orbit of the Earth (note the latitude of the landing is higher than the launch, see @DavidHammen's answer), and beyond that the mission involved firing ...


41

Bermuda was one of the tracking stations for the Mercury program. Bermuda was critical as it had a good view of much of the ascent trajectory. In this image, all of the tracking stations are shown along with one of the Mercury flight paths. BDA=Bermuda. Requirements. Early in the design of the Mercury system it was considered mandatory to receive ...


41

The first multistage rocket is much older then one might think. Its from the 14th century CE. Huolongchushui or fire dragon issuing from the water (Chinese: 火龙出水; pinyin: huolóngchushui; literally: 'fire dragon out of water') were the earliest form of multistage rockets and ballistic cruise missiles used in medieval China. The name of the weapon was used ...


41

I think that the timing of GPS signals was the first real necessity to apply General Relativity to spaceflight, or else precision would be much lower. According to (Ashby, 1997) and other sources I found the first GPS satellite launched in 1977 was used to prove that General Relativity will have a noticeable effect on the clocks. It turned out that the ...


40

(I'm interpreting the question as "what programming language was the first spacecraft software written in?", per discussion in comments above.) This will depend on your definitions of "computer" and "programming language". Almost certainly the first digital computers on spacecraft were programmed in assembly language or microcode. You can get a lot of ...


40

Let's start with the "Statement of Problem" in the anomaly report. ...the service module, upon being jettisoned on a lunar return flight, should have entered the earth's atmosphere, then skipped out into a highly elliptical earth orbit. Thus, the risk of recontact with the command module during entry would have been eliminated. However, on Apollo 8, 10 ...


37

As belief in conspiracy theories is associated with the rejection of science, it is likely that this answer will be rejected by many at the outset. If you doubt the reliability of science, perhaps you should check out this NPR article. Please note that it is an opinion piece. The author Alva Noë is a professor of philosophy at UC Berkeley, not a journalist. ...


37

The small separated cells had several functions. Six individual units, the "solar aspect cells", were each oriented and attached as if they were on the sides of a cube to identify the spacecraft's attitude. (This is probably the 2nd and 4th pictures above) This was a time when onboard electronics, and particularly computation, was expensive, so these were ...


35

We didn't know how hostile Venus's surface was, until we had landed there. The atmosphere of Venus makes it easier to land there than Mars. From Wikipedia, we learn: Before radio observations in the 1960s, many believed that Venus contained a lush, Earth-like environment. While there was some concept that Venus was hot, and had a high pressure, the exact ...


35

A transcript exists in the Apollo 11 Lunar Surface Journal, Postlanding Activities, with extensive annotations. The exchange begins at Mission Elapsed Time 104:59:27. Owen Garriott has just taken over as CapCom: 104:59:27 Garriott: Columbia, Houston. Over. 104:59:34 Collins: Columbia. Go. 104:59:35 Garriott: Columbia, Houston. We noticed you are ...


34

Yes. The fear that lunar dust was fine, deep, and motile enough that a lander could sink under its surface was mostly backed by Thomas Gold, a noted astrophysicist who was a consultant to NASA in the 1950s. Note especially in the image below of a Popular Mechanics article from 1964, the quote from his article in Science magazine on the subject: "Without ...


32

If Wikipedia page you link to can be trusted with dates, then she gave birth to her and Andriyan Nikolayev's daughter on 8 June 1964. Vostok 6 launched on 19 June 1963, and was in orbit a bit under 3 days. So unless she was pregnant for a bit under a year (352 days) which is impossible even for prodigious pregnancy considering early-term exposure of the ...


31

The Soviets had designed the Soyuz 7K-L1 as a part of the Zond program, with the aim of a manned flyby of the Moon. Artists rendition of the Soyuz 7K-L1 en-route to the Moon (Courtesy Wikimedia) Developed in the late 1960's, after political disputes regarding the expulsion of Nikita Khrushchev, it was originally designed to be assembled in-orbit. The ...


31

There are a few special things about Pluto, as compared to the other dwarf planets in the Kuiper belt. These include: It is the largest dwarf planet known, by diameter. (Note, this was only determined after the New Horizon's flyby) It orbits relatively close to the Sun, at times it is even closer than Neptune! It has the largest satellite system of any non-...


31

Pluto was discovered by a manual search of the sky using a blink comparator. This is an extremely laborious process. For Pluto, it made sense to go to all this trouble, because there were indications that a ninth planet had to be out there: Neptune's orbit was perturbed by the gravity of another planet, it seemed. Later, it turned out that that wasn't the ...


31

The first manned Soviet flight was Vostok 1 in 1961, and the first Soviet flight with a multiperson crew was Voskhod 1 in 1964. The Wikipedia article that you linked intends to say that Soyuz 1 was the first Soyuz mission with a crew. The anecdote about the wolves and bears comes from Voskhod 2 on March 19, 1965: For the Soviet crew of Voshod 2 [sic], ...


31

No, there have not. So far all astronauts have made it back to earth, though not all of them alive. The only casualties in space (above the Kármán line) are the crew of Soyuz 11 who were still in orbit when they died but about to reenter the atmosphere. All other casualties like Komarov in Soyuz 1 or the Columbia Space Shuttle disaster were during reentry ...


31

The early prototypes of the A4/V2 were painted in the familiar black-and-white roll pattern scheme. This scheme was designed to aid in tracking the rocket after launch. This pattern made it easy to observe any variation or roll of the rocket. The exact pattern was changed many times, and as with the rest of the rocket, the pattern was examined and ...


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