37

The Apollo Guidance Computer used a state vector either centered at the Earth or the Moon. The switchover point is the the lunar sphere of influence, defined in the AGC as 64,373,760 meters (https://www.ibiblio.org/apollo/NARA-SW/R-577-sec5-rev4-5.6-end.pdf PDF page 127). When in the idle program P00 the AGC will periodically check if it needs to update the ...


22

As I answered to another question: Both time and budget pressure forced the program to take risks that they might not have in an ideal situation. Flying live crews on Apollos 7 and 8 was part of that risk. Initially the plan was to fly a CSM and LM together in Earth orbit for Apollo 8. The LM was behind schedule and not ready for a test flight at the ...


21

In addition to the foreshortening illustrated by Organic Marble, the appearance of rocket plumes changes significantly with altitude. At higher altitudes, the pressure of the surrounding air is lower, the plume expands and dissipates faster, and less free oxygen is available for combustion with the fuel rich exhaust (which is the source of the bright yellow ...


18

The serial numbers of the Apollo spacesuits are documented on this NASA webpage. Each astronaut was assigned three suits for a particular mission: a Flight Suit, worn only during the mission; a Back-Up Suit; and a Training Suit. Some suits did double duty, most usually when an astronaut moved from a Back-Up crew to Primary crew for a later mission. The ...


13

As a complete vehicle, it was only the third flight. But the individual components had many previous flights, or weren't involved in the TLI. Let's look at the components from top to bottom. Launch escape tower. Prior to Apollo 8, this system had 2 launch pad abort tests, 4 flight abort tests on the Little Joe II rocket, and 2 abort tests on Saturn I ...


12

Spacecraft tracking in Apollo was done by the Unified S-Band (USB) system. It was called "unified" because it combined voice, tracking, telemetry, and computer commands. There was a completely different communication system (VHF) which did voice and television, but not tracking, and is not related to this question. Apollo 8 was an early manned ...


9

@russell-borogove explains that the plume changes during flight. We don't know the precise height when the two photographs were taken (both are labelled "climbing after lift-off" in the NASA archive). For a better comparison, I combined the two images and adjusted size and contrast to be roughly the same: My impression: There is a slight difference in the ...


5

Looks like Russell's right: Baker Nunn Satellite Tracking Cameras For a satellite photo run with the Baker Nunn camera the following operations occur: The Satellite Tracking Cameras consists of a continuous 35-mm length of film coming from a supply canister. The film is stopped for an exposure at the center of the film bridge and is then stretched ...


4

I believe the photo essentially received that name by acclamation. Before it came to be regarded as the name of the photo, it was the most natural, obvious, and succinct description of the contents of the photo. I recall seeing that photo in books and magazines with captions like "Earthrise as seen from Apollo 8." My sense is the word's evolution from ...


2

There are at least not any others in the onboard and air-to-ground transcripts, as far as I can see https://historycollection.jsc.nasa.gov/JSCHistoryPortal/history/mission_trans/AS08_TEC.PDF https://historycollection.jsc.nasa.gov/JSCHistoryPortal/history/mission_trans/AS08_CM.PDF Honeysuckle communications have been preserved and digitized, available for ...


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