On December 24th, Borman, Anders and Lovell fired the third stage’s engines to align for a lunar flyby and make preparations for translunar injection. Capcom Michael Collins gave approval and declared: ‘All clear for translunar injection!”
Houston trajectory specialists and computer wizards were overjoyed, knowing their calculations had come out correctly for once! What an incredible Christmas miracle!
Mission Planning
NASA was under great pressure in their race to land humans on the Moon. With Soviet launches of their Zond 5 already underway and showing that they might surpass Americans in landing humans there first, Flight Director Deke Slayton decided to hasten up their schedule by sending Apollo 8 for a flyby of the Moon instead of trying for a lunar landing attempt.
However, this alteration to their plan caused havoc with their crew schedules. McDivitt, Scott and Schweickart had been training hard for an Earth orbit mission to test out the Lunar Module; Slayton instead switched them with Borman, Lovell and Anders from Apollo 9 crew – suddenly leaving two to three months less training time than originally planned, with no time set aside for practicing their lunar module descent practice.
The astronauts were exhausted after months of intense training and eager to arrive at their destination of the Moon. To maximize the potential of their spacecraft and make use of any power left for remaining journey, they knew it was essential they remained awake while working as efficiently as possible without wasting precious power reserves that had limited availability for use throughout their trip.
Before setting out on their journey to the Moon, astronauts needed to demonstrate translunar injection, CSM navigation and communications midcourse corrections and passive thermal control as well as consumable assessment – using live data from tracking stations for their tests to be as accurate as possible.
Listen in on Rev 1 between Houston and the astronauts on Rev 1 at 00:52:44 GMT (00:52:44 AEST), recorded by Mike Dinn of Honeysuckle Creek using his tape recorder to monitor PAO audio, Net 1 voice loops and Houston’s downlink transmissions during this part of Rev 1. During this segment Houston played Herb Alpert’s Tijuana Brass.
Launch
Apollo 8 marked an historic event. For one thing, it marked the first time a crewed spacecraft left Earth’s pull and traveled into outer space towards the Moon and back again – breaking numerous records as it went. It also was one of the fastest journeys ever undertaken by humankind towards another world and set multiple speed records during that journey.
Once in space, astronauts broadcasted two live broadcasts to share their view of Earth and Moon with humanity. They also took extensive video footage, such as “Earthrise”, which became a global icon to help inspire global consciousness about protecting our home planet.
But all was not perfect. For instance, the SPS engine that would propel the craft into lunar orbit needed to fire exactly at the right moment or they risked ending up in an elliptical path instead of one close enough to capture gravity from Earth and Mars. Mission Control anxiously watched on.
They were rewarded for their patience: as soon as the precise moment arrived and passed, Apollo 8 signaled in predawn darkness that it had successfully achieved lunar orbit with Frank Borman, Jim Lovell and William Anders.
At that point, Mission Controllers realized something was amiss: SPS telemetry did not correspond with expected burn parameters. Carl Huss, who was working the Mission Control Center’s analysis desk at that moment, was called upon to conduct further investigation.
Orbital Entry
After their long, slow journey into orbit, the crew finally got their first view of the Moon’s crater-scarred surface through their 3 by 6 metre window while Houston broadcast the image over global tracking network TV screens worldwide.
The astronauts were eagerly awed, yet unimpressed with what they saw of the Moon from space. Unfortunately, its proximity allowed for Sun glare to completely obscure any detail on its surface – though their distant vision prompted much conversation and speculation regarding its nature.
Mike Collins announced, at exactly 002:27:21 GMT (146:31:26 AEST), “Apollo 8 – you’re go for TLI!” This marked the point at which after eight years of preparation the spacecraft would finally depart for its journey towards the Moon.
At an altitude of approximately 9,000 metres, the Apollo 11 spacecraft passed over the lunar surface. Borman and Lovell alternated sleeping between Command Module and Lunar Module as a safeguard against its reaching its maximum velocity and an unscheduled separation of both modules from each other.
At 5:04 GMT (20:04 AEST), the LM fired its service propulsion system engine for four minutes in order to reduce their speed and enter an elliptical lunar orbit of 111 by 312 kilometers. This was arguably the most hazardous portion of their flight as any malfunction could leave them with insufficient fuel to complete orbit around the Moon without ever finding rescue, creating one of the most thrilling moments ever witnessed by Honeysuckle Creek and all who live there.
Lunar Orbit
After conducting a comprehensive check of their spacecraft in Earth orbit, Commander Frank Borman, Command Module Pilot Jim Lovell and Lunar Module Pilot William Anders launched their spaceship at 4:03 am on December 24 to enter lunar orbit at 4:03 am on that same day – selecting this time because optimal lighting conditions existed at Apollo Landing Site 1 that they considered potential sites for landing the first manned lunar mission.
As they neared the Moon, Borman and Anders noticed a black, dusty planet appear through a window on Mission Control’s 3 by 6-metre screen – this marked the first planetary occultation seen by any manned spacecraft.
When the Moon came close enough, they fired the S-IVB’s Small Reaction Motor (SRM). Its short burn lasted only 2.4 seconds but successfully decreased their closest approach to lunar surface significantly – this would be its only SRM burn of their mission.
At Goldstone, astronauts used a telemetry system known as Quick Look to monitor the location of their spacecraft on the lunar surface. Additionally, they could view its thermal protection tiles and adapter for docking port on a Fairchild Slow Scan Television monitor located within their command module.
At 5:02:45 GMT (0553:45 AEST), on 24 December 2009, astronauts recorded a 25 minute TV broadcast featuring Jerry Carr speaking as the TV camera panned around their spacecraft. Bernard Scrivener at Honeysuckle transmitted downlink and digitalized tapes at NASA Hq; only Quindar tones had been removed as they had been filtered out at tracking stations to prevent interference with radio communications.
Return
At approximately 12:52:44 GMT on Christmas Day (Dec 27), Apollo 8 command module, or CM, performed its final double-skip maneuver to enter its re-entry trajectory back onto Earth. This maneuver required precise computer computations as one of its engine burns was among the most critical engine burns throughout its mission.
Borman began dozing off, while Lovell and Anders worked on computer and tracking systems. All were veterans of Gemini missions, having survived 14 days inside an airtight spacecraft in their previous mission.
At 06:10 GET, the computer conducted its final corrections to the spacecraft’s trajectory and course. At that same time, a midcourse burn with short tests of both its service propulsion system (SPS) motor used for lunar orbit insertion and return was conducted as well as its SPS motor which would later play an integral role.
This burn took place at an altitude of approximately 80,000 feet and SPS motor was fired for 2.4 seconds to test its performance, ultimately decreasing the spacecraft’s proximity to the Moon by approximately 740 miles.
At 9:51 GMT on December 27th, CM finally disengaged and returned to Earth’s atmosphere, skipping over lower layers into higher ones where its heat shield was hot enough to trigger deployment of its parachute.
It was an unforgettable spectacle as Apollo 11 entered Earth’s atmosphere without disembarking to form separate landing modules, creating a spectacular scene for control room staff at Carnarvon. Here you can hear communications from Apollo 11 through us (Kipp Teague’s Project Apollo Archive). This audio file runs for 5 minutes and 37 seconds.