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34

In order to prevent bacteria in the solid waste from producing gas, which could rupture the storage bags, a germicide was added to the bag after use and "kneaded in" to mix it with the waste once the bag was sealed. The germicide would kill the bacteria and render the potential poo-bomb inert. I haven't seen this germicide referred to as a "pill" ...


23

The obvious natural limit on amount of trash comes from the law of preservation of mass: they can't make more trash than the amount of material that was delivered by a delivery spacecraft with a resupply mission. They pack all the trash into bags kept for that specific purpose, and when a cargo spacecraft is to undock to be deorbited and burn up in the ...


17

When in doubt for such things, http://archive.org. https://archive.org/details/youtube-Y70SgYPIBGY Or if you prefer on YouTube


16

I found a sort of explanation in "Uplink-Downlink" the NASA history of the DSN. The first digit [range of digits, really, see the table] gives the geographical area. The second digit gives the antenna number within that geographical area. Sometimes the second digit is consistent for an antenna type (23, 33, 53 are OVLBI) but not always.


14

First things first: Lyndon Johnson had very little, if anything, to do with the site selection for what was then called the Manned Space Center. The selection of the current location of what is now known as the Johnson Space Center was made in September 1961, over two years before President Kennedy was assassinated. It was a very common ploy in those days ...


12

Looking at the history of DSN on Wikipedia, it appears that the tens-place digit originally was allocated to identify the region or site, and within a region/site the dishes were numbered sequentially as they came online, but some have been retired while others continued in operation, so the numbering is today a little irregular. In 1966, Goldstone ...


10

Despite the stated goal of shifting all US launches to the shuttle, all three major US uncrewed launcher families of the era remained in production. Each family reduced production and launch rates significantly during the early shuttle era (1981-1986), but I think there was a general sense even before the 1986 Challenger disaster that the shuttle wasn't ...


10

This is a NACA test of a 20-inch diameter ramjet in the Altitude Wind Tunnel (AWT) on February 7, 1946. The AWT analyzed the overall performance of ramjets at altitudes up to 47,000 feet. In this test, the ramjet was tested at altitudes ranging from 7000 to 41,500 feet and at ram-pressure ratios equivalent to free-stream Mach numbers as great as 1.84 using ...


8

A yaw thruster failed on in the Gemini's Orbital Attitude and Maneuvering System (OAMS) causing the attitude problems. Suspecting the Agena target to be at fault, they undocked, which made it worse because the spacecraft mass was now much less. The fix was to turn off the OAMS and switch to the redundant Re-entry Control System (RCS). This disabled the ...


8

Some Shuttle/ISS examples of crewmembers who completed training, were assigned to a flight, but declined/left/had issues/got reassigned: Joan Higginbotham. Left NASA after being assigned to her 2nd flight, STS-126. Jeff Ashby. Was assigned to his first flight as pilot of STS-87 but stepped down due to family issues. Went on to fly two flights as pilot and ...


6

For Space Shuttle: In the flight software, "tower clear" was defined as the end of the vertical rise phase when it was OK to start the Single Axis Rotation (aka "roll program"). This happened when the vehicle center of mass was at 376 feet above the Fischer Ellipsoid. Source - Ascent Nominal I-Loads Definition and Verification (not online) However, "...


6

Not really a "bail-out", but still a late change, was swapping the crews from Apollo 13 and Apollo 14. The original crew for Apollo 13 was to be commanded by Alan Shepard, but he had recently received surgery for an inner ear infection and NASA deemed he needed more time to recover for certain. So a crew led by Jim Lovell, slated for Apollo 14, was swapped ...


5

There is no connection between the current unmanned ARTEMIS mission and the recently proposed lunar lander. (Source: I'm the Science Operations Center manager for the current THEMIS and ARTEMIS missions.) The Artemis of mythology is associated with the moon, so it's easy to see how two different lunar projects might choose it for a name. In fact, there's ...


5

The scenario is presented by the 2019 Planetary Defense Conference.


5

That is a model of the SLS. ASA engineers and contractors tested four different payload configurations during the liftoff transition testing of a 67.5-inch model of the SLS at NASA Langley Research Center’s 14-by-22-foot subsonic wind tunnel in Hampton, Va.


5

Seems Like It Absurd hypotheticals aside, the Intergovernmental Agreement (IGA) specifies in Article V: [E]ach Partner shall retain jurisdiction and control over the elements it registers...and over personnel in or on the Space Station who are its nationals. This ESA resource summarizes: The Intergovernmental Agreement allows the Space Station ...


4

I think they did (page 120): The reference is a bit indirect, but the water storage was right next to the 'exercise ring' (storage lockers):


4

Tentatively, No It would appear the answer is no (to the absolute best of my googling ability). Only three astronauts have quit during training: Brian O'Leary in April 1968, John Llewellyn in September 1968, and Robb Kulin in August of 2018. O'Leary thought he would probably never fly, and Llewellyn had some issues with the required (at the time) jet ...


4

Because NASA Administrator Dan Goldin didn't like it. After hearing complaints from employees across the nation, new NASA Administrator Daniel S. Goldin announced unexpectedly on Friday that he was changing the agency's logo. Goldin killed the despised "worm," which spelled out "NASA" in high-tech red lettering, and restored the insignia ...


4

In his memoir "Liftoff", Michael Collins (Command Module pilot on Apollo 11) called it the sky. It is a quiet interval and we get a chance to examine our surroundings, this strange region called cislunar space. Is it daylight? Yes, the sun is definitely shining on us. Is it dark? Yes, if we shielded our eyes from the sun, the sky is flat black ...


4

Will NASA put astronauts into a polar lunar obit? Yes, but it's a bit complicated. If so, how? The current plan is not for an Apollo-like launch from Earth orbit to Lunar orbit, culminating in a landing descent from that orbit. Instead, the plan is to launch a crew from Earth on the Space Launch System to the Lunar Gateway, a mini-space station of ...


3

The Mercury missions really did have the potential to land anywhere around the globe. There was some automation, including an automated retrofire system to initiate re-entry, but it was not yet tested. Glenn and Carpenter had problems with the automatic system and each switched to manual control. Schirra's re-entry was entirely automatic, but he was ...


3

The paper Astrobee:Developing a Free-flyingRobot for the International Space Station explains the propulsion system rougly in two sentence: Astrobee’s propulsion system consists of a propulsion module on each of two sides of the free flyer (Figure3). Each module includes a centrifugal fan that pressurizes the module, and nozzles on the x, y, and z axes to ...


2

Alexey Leonov's crew was primary for doomed Soyuz-11. Two days before launch the crewman Valeri Kubasov had a heath issue, so the reserve crew was assigned. All three crewmembers died because of depressurisation just before atmospheric reentry.


2

I can't say for sure, I but would guess that it's due to maneuvers. There are other satellites in Libration Point Orbits that maneuver on the 2-3 week time frame. (They do so no matter what, it's not on an as-needed basis) Also there are a couple of factors associated with maneuvers that can preclude the ability to 'do science' on the spacecraft: The ...


1

Supplementary answer: the political role that Albert Thomas played in the site selection was not mentioned in the accepted answer. That includes the reason the Johnson Space Center, originally known as the Manned Spacecraft Center—was put in Houston in the first place. The year that Kennedy proposed traveling to the moon, 1961, it happened that U.S. ...


1

According to NASA: A green run is the first time the engines are assembled into a single configuration with the core stage and fired at nearly full-power. This will test the compatibility and functionality of the system to ensure a safe and viable design. NASASpaceFlight provides a bit more detail: [The SLS Green Run test] will essentially fly the ...


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