On Gagarin, Software Engineering and Neutron Stars

Today, April 12, is the International Day of Human Space Flight, designated to be so by the UN, in 2011, to mark the 50th anniversary of the first human flight, by Soviet cosmonaut, Yuri Gagarin.  Today it is exactly 60 years since that memorable flight.  It is also exactly 40 years since the very first Space Shuttle flight, on April 12, 1981.

Russians know this day as Cosmonautics Day (День Космона́втики) and still observe it as a big event.

In the west, people with interest in space exploration sometimes hold a party called "Yuri's Night".

https://yurisnight.net/about/ 

Yuri Gagarin was an extraordinary fellow.  His story is worth telling, so I will do that here.

He grew up hungry and in abject poverty in a Russian village, Klushino, occupied by Germans, with his family enduring very rough treatment by the Germans.

On the very first day, Germans burned down his school.  He learned to read from a discarded military manual.  The family was evicted from their house and forced to build a very small mud hut, where they lived for the next 21 months.   Their house was taken over by a Bavarian officer.

During that time, Germans, hunting for saboteurs, found Gagarin's little brother and hanged him from a tree.  Gagarin's mother found the boy at the last second and saved him.  His two older siblings were put on a "children's train" and deported to Germany (occupied Poland, actually) as slave labourers.  (They escaped, came back, and joined others fighting the Nazis.)  One day, there was a fighter plane dog-fight above the village and the Russian plane crash-landed nearby.  The pilot got out of the crashed plane and shortly thereafter was picked up by another plane and flown away.

That inspired Yuri's interest in planes.  He started building model planes.  After the Germans left, his family moved to nearby Gzhatsk, where his math teacher was a retired airman and an inspirational figure.  Gagarin, excelling in math and science, soon found his way into a technical college and then a flight academy.

Eventually, he became a pilot and joined the newly created space program.  The cosmonauts were required to be no taller than 170 cm (5'7").  Gagarin was 157 cm (5'2"), which was good news.  His modest origins also made him an ideal proletariat candidate in Soviet times.

He had great charisma and was well liked.  Almost all of his fellow cosmonauts voted him (anonymously) to be the best candidate for the flight.  He got selected.  However, the flight was extraordinarily dangerous and the odds of survival were estimated at 50%.  There were three variants of an official report prepared: one for success, another for the spacecraft not reaching orbit, and a third one for the cosmonaut getting killed. 

On re-entry, the two modules of the Vostok 1 spacecraft were to separate.  They didn't, and the whole craft started burning.  At that point, Gagarin thought that the mission - and his life - was over.  Eventually, after a while, the umbilical between the modules burned and his re-entry capsule was freed and could be saved.  However, the separation sent it into a violent, 8-g spin and the capsule began a flaming, gyrating tumble back to Earth.

The capsule was not designed for a safe, soft, survivable landing.  In order to survive, Gagarin had to overcome this sickening spin, fight the g-forces, exit the cabin, and independently parachute to earth.  He managed to do that and survived.

A woman and a girl, working in a field, saw him, in an orange space suit, falling from the sky and they were frightened.  "I'm a friend!" he shouted.  "Have you come from outer space?" they asked.  "As a matter of fact, I have!" he replied.

So he survived and became a hero.  His popularity, not only in the East but also in the West, was great and somewhat unexpected, even shocking, for the establishment on both sides.

He travelled the world as an ambassador of Soviet accomplishments and was surprisingly warmly received by both the people and the politicians, even royalty.  When invited to have lunch with Queen Elizabeth II, he was served tea with lemon, not milk as British do, because that's how Russians drink their tea.  After he had his tea, Gagarin took the lemon out and ate it, shocking everyone.  Without skipping a beat, the Queen pulled the lemon out of her tea as well and did the same.  Other guests followed and the awkward moment was resolved.

Later, when the Queen made a photo with him contrary to etiquette, she explained that this was OK, because Gagarin was "not an ordinary man but a man from space".

When Gagarin came back home, authorities did not want him to fly again, afraid that he, a popular hero, could get killed.  However, he insisted and was selected for a flight of Soyuz I.  Eventually, his friend Vladimir Komarov  replaced him, and Gagarin  remained as a backup pilot.   The launch was rushed and went on despite Gagarin's protests about safety.  The re-entry ended badly, and Komarov got killed.

For his safety, Gagarin  was then completely banned from space flights and from flying planes solo, as well.  However, it did not help.  When flying on a routine training mission with an instructor, his  jet crashed and Gagarin was killed.  Before his space flight in 1961, Gagarin wrote a goodbye letter to his wife.  This letter was delivered to her after this crash, in 1968.

The cause of the crash is somewhat shrouded in mystery, but some sources suggest that a nearby Sukhoi Su-15, flying against regulations too low, broke the sound barrier very close to Gagarin's plane, and the resulting turbulence caused his plane to crash.

I personally never liked the figure of Yuri Gagarin, because, for me, he was the emblem of the never-ending Russian and Soviet propaganda, for which I always had a great deal of animosity.  However, objectively speaking, he was a remarkable man, worthy of his status of a hero.

Gagarin was known not only for his charming smile and an easy-going personality, but also his somewhat famous informal exclamation  Поехали!  (Poekhali! Here we go!)  at the moment of the launch.

Gagarin's flight had far-reaching consequences.  The very next day, many US congressmen pledged to put up money for the US to catch up.   By the end of the following month, the US committed itself to put a man on the Moon before the end of the decade.  That spurred an enormous level of innovation and propelled the US to technological heights far above others. 

4% of the budget was pumped into NASA (today it's about 0.5%).  In the years that followed, 400,000 people worked day and night on exceedingly difficult engineering and scientific problems and solved them.  The interest and enrollment in physics, computer science and science in general substantially increased.

The efforts of the Apollo mission to the Moon resulted in many positive outcomes.   Some of the innovations in computer design can be felt to this day.  The navigational computer that was designed and built for the mission was a marvel of engineering, compact and powerful well beyond the norms of the day.

The software for it, written by a team of several hundred software engineers, lead by Margaret Hamilton, was designed exceptionally well with an exceptional level of safety mechanisms.  That came handy when, three minutes before touch-down on the Moon, a plethora of alarms suddenly erupted, bombarding the astronauts with many "never supposed to happen" priority alarm displays.  That would normally have meant to abort the landing or worse.

However, Hamilton had already prepared for such unexpected situations in the years of design, planning and coding before the flight.  Her automatic software response worked and allowed the astronauts  to continue the flight and save the landing.   A crucial component in those events and their resolution was also the fantastic asynchronous executive, designed by J. Halcombe Laning,  which was a remarkable piece of engineering, even by today's standards.

Note: various versions and details of the story also include the description of an unexpected sequence of repeated "infamous" 1201/1202 errors.  Neil Armstrong's heart rate rose from 120 to 150 during this period.

Another consequence of the space flight was a sudden, urgent worry about the on-going arms race possibly extending into space.  That was not a thought entirely without merit.  The American A119  program planned to do exactly that, and the Soviets had their own plans.  Eventually, the US, the Soviet Union and the others, too, signed a treaty that prohibited placing or testing nuclear weapons in space (as well as atmospheric and other tests, except for underground tests). 
 

In the effort to monitor and enforce that treaty, the US developed a system of Vela satellites that were designed to detect bursts of gamma radiation associated with nuclear explosions.  No such bursts were ever detected (except for the so-called Vela Incident, between South Africa and Antarctica, which remains inconclusive and not fully explained, but was probably not caused by a nuclear explosion).

However, the satellites did detect gamma bursts from space: these were mysteriously coming out of nowhere.  Eventually, their origins were found to be far away galaxies, so distant, that they were not visible even with the largest telescopes.  These bursts are the most energetic events in the Universe, capable of inflicting great damage on objects many light years away.  After many subsequent observations, much modelling, followed by building and deploying additional, dedicated satellites, only now, 50 years later, we are beginning to understand their nature.

 

It seems that many of the bursts are coming from the far reaches of the Universe, some originating from as far as 12 billion light years away.  They are likely produced by a merger of two neutron stars or a neutron star and a black hole.  Our newfound ability to search for them and observe them in greater detail is offering us a new look at the universe.