The story of the UFO that followed Apollo 11...
On July 19, 1969, during the TLC, the Apollo 11 crew spotted a very bright rotating object that seemed to be following them at a distance...Among the most persistent urban legends is the one claiming that an unidentified flying object (UFO or UAP) escorted Apollo 11 on its journey to the Moon. The story, which has fueled decades of UFO speculation, began on July 19, 1969, when the crew noticed a persistent, pulsating reflection that seemed to move parallel to their trajectory, keeping a constant distance and speed. It was not just a bright spot: the object looked solid, with a defined geometry that changed cyclically from a cylindrical shape to a structure resembling an "L". To try to clear up the mystery, the astronauts used the optical telescope of the navigation station in the Command Module, a high-precision instrument normally used to align the spacecraft's "inner ear" (the IMU inertial platform) with the stars. Yet not even optical magnification allowed a definite identification; the object remained an elusive glint, a presence that, in the absolute vacuum of deep space , appeared as real as it was inexplicable. The mood on board grew tense, not so much because of fears of the paranormal as because of the strategic implications of being shadowed. These were the years of the Cold War and the space race was at its peak: the suspicion that crept among Armstrong, Aldrin and Collins was that it might be a Soviet spacecraft, an automated probe or an interceptor sent by the Kremlin to disrupt, sabotage or simply symbolically beat the American mission. In hindsight, these suspicions were not unfounded at all: in those very days, the Russian probe Luna 15 was on its way to the lunar surface in a desperate attempt to
To try to identify it, the crew tried to observe it through the telescope of the onboard navigation station, but all they could see was a slowly rotating object, vaguely "L"-shaped... collect soil samples and bring them back to Earth before the United States. The idea of Russian interference was a real and calculated risk. To get answers, the crew contacted the Mission Control Center (MCC) in Houston, asking with apparent nonchalance how far away the Saturn V third stage (S-IVB) was, hoping that their mysterious traveling companion was simply their "heroic launcher", now inert and drifting. Mission Control's answer, however, dashed those hopes: the S-IVB stage was more than 10,000 kilometers away. It was physically impossible for it to be the object they had in sight! The object followed the docked spacecraft stack, the so-called "Apollo space train", made up of the Command and Service Module (CSM) and the Lunar Module (LM), for hours, then disappeared from view for good... For years this ballistic discrepancy has been the cornerstone of the conspiracy narrative of "alien contact". Scientific reality, however, is much more straightforward and lies in the 
Detail of the S-IVB stage of Apollo 7's Saturn IB, with the SLA adapter opened into 4 petal-shaped panels. On the lunar versions these panels separated and drifted off into space. Photo courtesy of NASA.design details of the mission that conspiracy theorists systematically leave out. After the translunar injection (TLI) burn, the maneuver that sent the astronauts toward the Moon, in order to extract the Lunar Module "Eagle" from the third stage, the four protective panels that made up the SLA (Spacecraft Lunar Module Adapter) were blown off; the SLA was a kind of space garage that protected the LM during launch. These panels, nicknamed "petals" because of the way they opened, were massive structures of shiny aluminum several meters long. Once released by the controlled firing of special pyrotechnic bolts and pushed away by dedicated springs, the petals did not drift away from the third stage evenly: because of the lack of atmosphere and the tiny difference in the thrust they received, one of them kept traveling by inertia on a trajectory almost identical to that of the CSM "Columbia". What the astronauts were watching through the telescope was, in all likelihood, one of these very SLA petals , slowly rotating. The rotation made the metal surface reflect sunlight like a mirror, creating the intermittent glint and the changing geometric shapes that had so intrigued the crew. In deep space, with no reference points and no atmospheric perspective, judging the distance of a reflective object is a hopeless task: an aluminum petal 20 or 30 kilometers away, lit by the Sun without the filter of air, can look indistinguishable from a huge spacecraft hundreds of kilometers away. The "alien escort" theory collapses for good when you look at celestial mechanics: an object released from a spacecraft without significant retrograde or lateral thrust will remain for days inside the same gravitational "bubble" , following its source like a silent companion. The request for clarification sent to Houston was not driven by terror of the unknown, but by the strict professional need to map every piece of nearby debris in order to avoid collisions during attitude maneuvers or during the upcoming braking burn for lunar orbit insertion. The conspiracy fantasies of an extraterrestrial escort are therefore the product of a Hollywood view of physics, which prefers to ignore the "technological junk" produced by human ingenuity and take refuge in UFO folklore. Apollo 11 was not being followed by alien intelligences, but by the remains of the metal shell that had protected it during launch, a fragment of aluminum that, reflecting the Sun, ended its journey crashing somewhere on the surface of the Moon: and perhaps it was not the only one.
