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70

Your picture is not of a Saturn V, it's of a Saturn IB. The purpose of the elevated platform (known as the "milkstool") is to lift the rocket up so that it can be launched from Pad 39B using the same connections to the launch tower that the much taller Saturn V used. The early Saturn IB launches used the shorter Pad 34 and Pad 37, but by 1973, those launch ...


65

Background I believe the astronomy.com article is essentially accurate. The story of the Skylab 4 "mutiny" or "strike" has been greatly exaggerated. The crew took a scheduled rest day instead of working through it as they'd done with previous scheduled rest days (and in fact they actually continued to work, albeit at a relaxed pace). This isn't a new ...


41

Seats were installed in the lower equipment bay, instead of some of the usual storage lockers. A Skylab rescue mission would take a few days at most, so the usual luxuries for a 2-week Apollo mission (like being able to go to the lower equipment bay for a little personal-hygiene privacy) could be foregone. The extra seats were mounted in the reverse ...


32

Short answer is that there were multiple contributors: bad predictions of how long the orbit would last, schedule delays on the Space Shuttle, and cost/benefit analysis of a last minute rescue mission for an aged space station. Things to keep in mind: Skylab reentered and burned up in July 1979 the last Apollo capsule to fly was the Apollo-Soyuz Test ...


30

Offered as a supplement, since no one has posted a direct size comparison: The height difference in the Saturn V and Saturn 1-B is clear in this image. Edit: SA-1 through -9 are Saturn 1s, SA-201 through -205 are 1-Bs, the last 2 are Vs. The mission payloads, from left to right: SA-1, development flight with dummy second stage and payload SA-4, more ...


28

Skylab's science experiments included Earth surface observations, and the higher inclination orbit allowed more surface to be viewed. Per Living and Working In Space: The NASA History of Skylab: The requirements of the earth-resource experiments caused major changes to mission plans. Primary among these was an increase in orbital inclination to 50º. Skylab ...


16

The Instrument Unit was retained after Skylab reached orbit, and was instrumental (sorry) in configuring the station for orbital operations. From Skylab: A Guidebook: Control of the Saturn V launch vehicle during launch and powered flight will be accomplished by guidance and control systems located in the Instrument Unit. This function will be maintained by ...


14

A little digging into KSC Launch Complex 39's Wikipedia page and I found this. A total of thirteen Saturn Vs were launched for Apollo, and the unmanned launch of the Skylab space station in 1973. The mobile launchers were then modified for the shorter Saturn IB rockets, by adding a "milk-stool" extension platform to the launch pedestal, so that the S-IVB ...


13

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):


13

Things started badly, the astronauts tried to hide Astronaut Pogue’s vomiting. NASA had to figure it out on their own. If there is anything that smacks of mutiny, it’s this because it violates mission rules. NASA never used the word mutiny, but ‘reprimand’ was tossed around. Story from back then: https://www.nytimes.com/1973/11/18/archives/skylab-...


12

There's a detailed reconstruction in NASA Technical Memorandum 78308 Skylab Orbital Lifetime Prediction and Decay Analysis The assumed Skylab breakup scenario was as follows: The OWS SAS array (aerodynamically) off at 62 nmi. The ATM separates from the remaining OWS at 54 nmi. ATM SAS arrays separate from the vehicle between 54 to 50 nmi ATM and OWS ...


11

There's a great writeup on this in the NASA tech paper The Skylab Parasol. Big picture, the parasol was packed into an airtight box that attached to the inner door of one of the scientific airlocks. This airtight box preserved the Skylab's pressure integrity since both airlock doors would have to be opened at the same time. The box/rod system had previously ...


9

The Silverbird calculator says about 107 tons payload plus the 11 ton payload shroud, for a total of 118 tons to 185km x 185km at 28.5 degrees. I've been refining a general rocket launch simulation program over the last few years, modeling it on the work described here by Robert Braeunig. According to my current version of the simulation, it's possible to ...


9

Yes, here it is: Two precise control systems permitted the astronauts to orient the workshop to collect experimental data and to position Skylab so that its solar arrays faced the Sun. That means that the solar panels were fixed, and that the whole station was oriented so they faced the Sun. This kind of rotation is quasi-inertial, as fixed relative to ...


9

Similarly to night vision devices, the light sensitive part is the photocathode, which releases electrons when hit by photons. The electrons at the photocathode are accelerated by the -25 kilovolt bias, which allows them to be focused with good resolution onto a film surface using the magnetic field. "Electrographic cameras for the vacuum ultraviolet&...


6

It appears to have actually been a pole, not a cord. Handrails and handholds, colored blue for quick identification, were located throughout Skylab. A removable, collapsible "fireman's pole" extending from the workshop hatch to the floor of the forward compartment provided a means of rapid movement. However, the astronauts soon found that they ...


5

This New York Times article about Jack Kinzler, the inventor of the Skylab parasol seems to answer that. The parasol was built out of telescoping fishing rods, spring loaded. Which means the structure could be compressed into the airlock, the inner hatch closed, and when the outer hatch was opened, the spring would uncompress. No separate deployment control ...


5

The paint, as can be seen from this article, contains a titanium-oxide semiconductor. The spectral measurements of the paint are similar for J002E3 as they were from measurements taken shortly after launch, showing that the paint still performs well even after over 30 years in orbit, for the Apollo 12 mission. The paint simply serves as a thermal control ...


4

Short answer: No, for several reasons. Longer answer: the apparent gravity from centripetal acceleration was low, and the astronauts likely didn't have enough exposure to get any real benefit. I'm going to have to dig up long unused physics knowledge here. The formula for centripetal acceleration is ac = v2 / r, in other words centripetal acceleration is ...


4

Here is a schematic of the shower system. A description from here. This is an enclosure which uses continuous airflow as a gravity substitute to move the water over the crewman. A 6-pound capacity water bottle is filled from the waste management compartment water heater, pressurized with nitrogen, and attached to the grid ceiling at the shower ...


4

Yes, but the EVAs were to mount and unmount cameras, not to look at it with their own eyes There were 13 experiments during Skylab 4 to observe various characteristics of the comet Kohoutek. There are described in the NASA technical report MSFC Skylab Kohoutek Experiments Mission Evaluation. The mission summary clearly states that EVAs were involved: The ...


4

According to this webpage, under the payload shroud were the airlock, the multiple docking adapter, and the Apollo telescope mount. The latter was folded in front of them but swung to the side on orbit entry. The Saturn Instrumentation Unit (I.U.) was also above the third stage.


3

(After 13 days, no one has answered this question, so I researched it myself.) According to Skylab: A Guidebook, Solar energy is the prime source of electric power on Skylab. Two systems of solar-electric cell arrays, one on the Workshop [OWS] and one on the Apollo Telescope Mount [ATM], will be deployed after the Skylab cluster has reached orbit. The OWS ...


3

The Skylab crew exercised using a bicycle ergometer, not by running around the ring of storage lockers. Image credit - NASA Per the answer to this question Did NASA tell the Skylab astronauts to "Stop running around!"? the crew was directed to not run around the ring of storage lockers any more. They experienced the usual loss of bone minerals. ...


3

Only 39 orbits were Earth-oriented. The overwhelming majority of the station's operating life was Sun-oriented. The final Earth resources experiment package pass for Skylab 3 ended, In all, 39 Earth-oriented passes, six solar inertial passes, two Earth-limb surveys, and two lunar calibration sequences were completed. Skylab: A Chronology, 1973 September 21 ...


1

tl;dr: I get good agreement with @JCRM's estimate! Moments of inertia found in NASA TM X-64746 Skylab Attitude Control and Angular Momentum Desaturation with One Double-Gimbaled Control Moment Gyro also found archived here: Command/Service Module undocked docked Minimum Moment-of-...


1

@RussellBorogove's comment is fairly conclusive. ...I note that Celestrak was established in 1985, at which point Salyut 7 was up, but Skylab was not. The Archived TLE data page says 1980-2004, but there's a link to request earlier data. Skylab reentered the atmosphere before 1980 and Tiangong-1 and Tiangong-2 were both launched after 2004. And, as ...


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