Tag Archives: spaceflight

668. Century Ships

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Joachim Boaz at Science Fiction and Other Suspect Ruminations has been running a series of reviews on century ship stories. He does a good job, even providing links so you can read the story itself before or after reading his review. I’ve read two of them, both story and review, picked out because they were by Brunner and Ballard.

Century ship stories are an extreme version of slow starship stories, that is, stories about exploration in ships which do not travel faster than light. Century ship stories assume that the people who start the journey will not live to complete it. It will be completed by their descendants who, when they arrive, will never have lived anywhere but on the ship.

That sounds like a recipe for disaster, and it typically is. A reversion to barbarism along with a superstitious belief that nothing outside the ship actually exists is a common trope. The original Star Trek used it in For the World is Hollow, and I Have Touched the Sky.

I first encountered century ships before I reached high school in The Forgotten Star, a top notch juvenile which has, ironically, been forgotten. It takes place in our solar system, before star flight; the young heroes discover that Ceres isn’t really an asteroid, but a century ship from elsewhere.

The first time I read a century ship story told from the occupants’ viewpoint was Heinlein’s Orphans of the Sky. It was such a dreary presentation of the “we forgot this is a starship” trope that I never returned to it, and it pretty much put me off century ship stories for a long time.

On the other hand, slow — but not that slow — starship stories are my bread and butter. They take relativity more or less seriously, and offer all kinds of complications through the slowing of time at the approach of lightspeed. Heinlein did it well in the juvenile Time for the Stars. Other authors had milked the concept for its considerable potential for weirdness.

At nearly the speed of light a trip to the stars will seem quick, no matter how many years pass back on Earth, but getting up to the speed of light is an issue is two senses.

First, it will require power on the order of what would come from the total annihilation of matter. This generally requires a MUD (magical unexplained dingus). Slipstick Libby invented one, but usually Heinlein got there by torch ship (what a wonderful name!), a MUD he never bothered to explain. When I needed that much power in Cyan, I invoked Lassiter’s Anomaly as an ersatz explanation. This gave my core ships a nice philosophical underpinning, like E. E. Smith’s Bergenholm which cancelled inertia, but core ships are still MUDs.

Given the power, however you get it, relativistic starflight still has the problem of acceleration time. True, time slows down at near lightspeed, but you have to get there first. If you are an honest writer who takes the time to look at Einstein’s simpler equations, you will realize that it takes a long time to approach lightspeed at an acceleration that wouldn’t squash a human flat.

I did the math for Cyan, and it turned out that a one-way trip to Procyon — accelerating at one gee, coasting, then decelerating at one gee — took three years subjective while twelve years passed on Earth and Cyan. That’s a six year round trip for the ten crewmen, which calls for a lot of games of chess and a lot of intimate human interactions. If you’ve read Cyan, you know what I mean.

As a side note for new writers looking for a useful tip, that coasting stage is a near-freebie. A ten light year or a hundred light year trip would take about the same subjective time, but the time differential between the crew and the folks back home would become immense.

Later in the book, sending colonists took a whole different set of calculations. Accelerating to half the speed of light takes a tiny fraction of the fuel needed to accelerate to near lightspeed, so the colony ships were even-slower-starships, though still not nearly as slow as century ships. Call it twenty years, one way.

How do you get tens of thousands of people into a small space and keep them from killing each other over twenty years? Freeze them. Given the technology of 2107, that meant a twenty percent loss of life among those who chose to go.

Cold blooded? (Forgive the pun.) Not when you consider the conditions they were fleeing.

While the colonist were on their way toward Cyan, a group of beltmen (denizens of the asteroid belt) were also planning an escape. They were already used to living in space; many of them were born there. A long slow trip in a small habitat did not deter them, but the eighty year voyage to Sirius had a lot of unintended consequences. Not quite a century ship perhaps, but close enough.

Of course if you have been following this blog during the last six months you realize that I am talking about Dreamsinger, the sequel I am working on now.

Further down the to-write list is a sequel to the sequel to A Fond Farewell to Dying which concerns a hyper-century ship built around memory taping and a few frozen stem cells. That one doesn’t turn out the way its originators planned either.

I guess the trauma of reading Orphans of the Sky at a tender age hasn’t completely put me off century ships after all.

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643. Apollo 12

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Everybody knows about Apollo 11, especially since its fiftieth anniversary last July. And then there’s Apollo 13 which was crewed by Tom Hanks, Bill Paxton, and Kevin Bacon, with Gary Sinise working hard in the simulator. Or so America remembers it.

Quiz: match the actual Apollo 13 astronauts with the actors who played them.

Answers: Jim Lovell (commander), Fred Haise (lunar module pilot), and Jack Sweigert (command module pilot). Ken Matingly was the astronaut who got bumped for a disease he didn’t have.

That’s it. The average American knows one flight, one movie, and may vaguely remember something about the Bible being read from the moon. It was lunar orbit, actually, on Apollo 8.

There were six moon landings; five of them are essentially forgotten. Apollo 12 was the second landing, and today it has reached its fiftieth anniversary with none of the mega-hype we saw in July. If Apollo 11 had aborted at some point, and Apollo 12 has succeeded exactly as it did, all the hype would be today, and no one would remember Neil Armstrong.

Query: who was the next person to fly the Atlantic solo non-stop after Lindbergh. Answer: I have no idea, either.

For the record, the crew of Apollo 12 consisted of Pete Conrad (commander), Alan Bean (lunar module pilot), and Dick Gordon (command module pilot).

The countdown for Apollo 12 started at midnight Nov. 9th, 98 hours before scheduled launch. Zero and liftoff, was reached after several holds, some planned, some not, at 16:22 GMT (22 minutes after noon, local time) fifty years ago today.

36 seconds into the fight, Apollo 12 was struck by lightning. 52 seconds into the flight, it was struck again.

Every light on the boards went on at once. No one had seen such a display of dismay on any flight or in any simulation. Conrad said, “I don’t know what happened here; we had everything in the world drop out.”

NASA had made the launch despite a thunderstorm, for reasons no one seems to be able to nail down. The surge of power from the two strikes caused most of the electrical system to shut down, rather like a home surge protector shutting down power to save a computer. The crew rode out the emergency until they reached a stable orbit, then got to work reestablishing their connection to the fuel cells.

As if that weren’t enough, the automated navigation system was no longer working. They had to use a sextant (a high tech one, of course) to establish their position by shooting a pair of stars.

Two hours and fifty three minutes after liftoff, the final stage of the Saturn V fired again and put them on a trajectory for the moon.

*          *          *

The moon landing was routine — which is to say, very much like Apollo 11 — which is to say, scary as hell.

They did not have a computer data overload like the one in Apollo 11 that made it look like they were going to crash. They had already had their electrical overload on liftoff.

They came down precisely where they were supposed to. What made it a scary-same-as was that the immediate area where they had planned to land was covered with small craters and boulders, and they had to search around for an area that wasn’t. Conrad flew the LEM while Bean kept his eyes on the instruments. As he swung them around toward his left, the LEM tilted crazily. Then Conrad found a clear spot and came down to land.

Landing on the moon throws up a storm of dust and small particles that obscure the ground and can damage the spacecraft. In the low gravity, it all takes a while to settle. One of the probes on the four feet of the lander touched the moon, a light came up on Bean’s board and he relayed the message. Conrad cut the rocket and the LEM fell, slowly due to the low gravity, to the moon’s surface.

As planned, not counting having to search for an alternate landing site.

Here’s a side note on what it is like to want to know things. I have been aware since the sixties that the LEM balances on the thrust of its rocket engine, and moves sideways to find a place to land. But how did it move sideways? Were there side thrusters like the ones which move big ships away from the dock? Was the main engine gimbaled? No, it turns out, the whole craft is tilted, so the main engine can move them sideways, operating like a helicopter.

So how do they tilt the LEM? Do they use the same attitude thrusters that change its orientation in space? That seems likely, but I’m not sure. Learning one thing just makes me curious to learn another.

Once they were down, there was work to do. In addition to the exploring and sample collecting like Apollo 11, they also set up the ALSEP (Apollo Lunar Surface Experiments Package) which would continue gathering and relaying information long after their moon walks were over. Conrad and Bean did two moon walks, and on the second one walked to the nearby Surveyor III spacecraft, the unmanned soft landing vehicle which had surveyed their landing site two years earlier. They removed a few parts for analysis back on Earth.

Once their time on the lunar surface was over and the LEM upper stage had rejoined the CSM, the LEM descent stage was given a controlled burn by remote control, then allowed to crash back to the lunar surface. This gave a test “seismic” event to calibrate the ALSEP. So if anyone mentions those six LEM descent stages still sitting on the moon, you can tell them no, there are five.

Apollo 12 splashed down late on November 24th. By the time it was launched, politicians were already dismantling Apollo, and America was yawning. We set out to beat the Russkies and we did it, so why were we still going to the moon?

Politics and public opinion work that way; science doesn’t. No one ever did one experiment and said he had the answer to any problem. No geologist ever looked at one tiny patch of ground and said he understood the whole Earth. Fifty missions would not have been too many to settle scientific questions about the moon, especially since each mission would have likely generated new and deeper questions.

Nevertheless, after November of 1969, only four more missions would land on the moon. Apollo 13 would fail to land, and Apollos 18, 19, and 20 would be cancelled.

Pete Conrad went on to command the first manned mission to Skylab. He died in 1999. (For information on Skylab, see posts 297, 298, and 299.)

Dick Gordon was backup Commander to Apollo 15 and was scheduled to finally land on the moon as Commander of Apollo 18, until it was cancelled. He died in 2017.

Alan Bean Commanded the second manned mission to Skylab and was backup Commander for the Apollo-Soyuz mission. He died in 2018.

After leaving NASA, Bean studied art and became a painter of lunar subjects. He said, “I’m the only man who can paint the moon, because I’m the only one who knows whether that’s right or not.”

There are about a million books on Apollos 11 and 13, but locally I could only find one book on Apollo 12. Fortunately, that one was full of Bean’s own recollections and paintings. See Apollo: an eyewitness account.

634. A Tribute to Alexi Leonov

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This is a substitute post. The one I had planned about my two latest animal neighbors will have to be pushed forward to sometime in late November, probably just before Thanksgiving.

The reason for the change is that Alexi Leonov died in Moscow on October 11, and I just became aware of it tonight (Oct. 15). You’ve probably never heard of Leonov, and that is a shame. He was the first person to walk in space, in a flight filled with incredible dangers. I wrote a post about the flight for its 51st anniversary, called Spacecraft Threatened by Bears. I will present it again below, changed only by the addition of a few links to other related posts.

Spacecraft Threatened by Bears

Yes, I agree; it’s a snarky title. It’s also accurate, believe it or not.

I had the great good fortune of living through the early days of manned space flight. I was nine years old when the Russians orbited the first satellite, and the early manned flights came when I was in high school. I watched every American launch with fascination and envy, but the Russian launches were shrouded in secrecy. I knew only the bare minimum that all Americans knew. I’m not sure the president knew much more.

During those early days, nothing was routine. Every mission was dangerous. They still are, of course, but not so much as then. American failures were there for all the world to see, while the Soviets kept their’s secret. After the breakup of the Soviet Union, information about the early Russian space program became generally available, but by then few people cared. I did, and I sought out the stories.

Today is the fifty-first anniversary of the first space walk — by the USSR. I would have brought it to you on the fiftieth anniversary, but I wasn’t blogging yet. Voskhod 2 was a triumph, and also a flight which went spectacularly awry.

Voskhod 2

March 18-19, 1965

The first six manned Soviet spaceflights were aboard Vostok craft. Gagarin became the first man in space on Vostok 1, Tereshkova became the first woman in space on Vostok 6. I plan to talk about them on their anniversaries, in April and June.  [For those posts, see 131. First Into Space, 132. Chasing Cosmonauts, and 168. A Woman in Space.]

Vostok astronauts wore space suits throughout their flights and landed by personal parachute separate from the descent module. Before the second generation Soyuz spacecraft came on line, the Soviets launched two additional manned missions on modified Vostoks called Voskhod.

On Voskhod, a backup solid fuel retrorocket was added to the spherical descent module, another additional rocket softened the landing so that the cosmonauts could remain within the descent module, and the ejection seat was no longer used. This allowed Voskhod 1 to carry three astronauts where Vostok had carried only one.

Voskhod 1 cosmonauts flew without space suits, as did early Soyuz missions. Voskhod 2 cosmonauts Belyayev and Leonov wore space suits because they were scheduled for the first space walk. Their craft also carried an inflatable airlock.

American space walks first took place during the Gemini program (see post 87). That craft had two hatches but no airlock; both astronauts were in vacuum during the entire spacewalk.

On Voskhod 2, Leonov crawled into the airlock, sealed the inner door and opened the outer one. Belyayev remained in the pressurized descent module.

For ten minutes, Leonov remained within the airlock but exposed to the vacuum of space, then he slipped free and floated on a tether for another ten minutes. He was called back in to terminate his space walk, and his difficulties began.

(Or perhaps they had already begun. Some sources state that he “experienced a disorienting euphoria” during the space walk and other sources state that he suffered bends-like symptoms after the space walk was over; I haven’t been able to confirm these statements.)

It is certain that he had extreme difficulty reentering the airlock. His space suit had over inflated; the boots and gloves had slipped beyond his toes and fingertips, and his suit had increased in girth. He had to vent part of his rapidly depleting oxygen in order to bring his suit down in size, and even then had to enter the airlock head first, instead of feet first as planned. Once inside the airlock, he had extreme difficulty contorting his body to close the outer door. All the time, his body was heating up dangerously. Since he was surrounded by vacuum, there was nothing to carry away the heat his body was generating.

Once air pressure had been restored in the airlock, Belyayev opened the inner door and Leonov was safe. For the moment. As he said in an article for Smithsonian’s Air and Space magazine in 2005, “the difficulties I experienced reentering the spacecraft were just the start of a series of dire emergencies that almost cost us our lives.”

The mission had achieved it’s goal and it was time to return, but just before the scheduled time for firing retro rockets the cosmonauts discovered that their automatic guidance system was malfunctioning. It took time to prepare for manual entry, so they had to wait one orbit, which would make them miss their return point by a thousand miles. Most of that orbit they were out of radio communications. When communications were restored, ground control asked them where they had landed, not knowing of their difficulties.

Their orbit was set, but the time they would fire their retro rockets would determine where on that orbit they would land. They chose a target just past the Urals. Using the clumsy and difficult manual backup equipment, they achieved the correct attitude and fired the retro rockets in the conical rear portion of the craft called the orbital module. The orbital and landing modules were supposed to separate ten seconds after retrofire. They didn’t.

The two cosmonauts knew immediately that something was terribly wrong. Instead of the steady press of force against their backs as they decelerated, they found themselves whipped about by confused forces that exceeded ten gravities. A communication cable between the two modules had failed to release, and now both modules were spinning about each other, tethered by the cable.

Finally, about 60 miles up, the cable burned through and the cosmonauts were freed. The drogue chute deployed, and then the main chute. All was peaceful and in order – briefly. Then it became dark as they dropped below cloud cover, the final rocket fired to slow them to landing speed, and they landed in 6 feet of snow.

They were 1200 miles beyond their intended landing point.

They blew the explosive bolts to release the hatch. It didn’t open. They had landed in the middle of a forest and the hatch was held shut by a tree. By yanking violently they dislodged it and it fell away, lost in the snow.

They made their way out of the spacecraft and waded through snow to a small clearing. Bikonur had not heard their landing signal, but a passing cargo plane had. It circled, and was soon joined by other planes and helicopters, but none of them could land in the rough taiga. Pilots threw a bottle of cognac; it broke. They threw warm clothing which got caught in the trees, but at least two pairs of wolfskin boots made it to the ground.

The light was failing. The cosmonauts returned to their landing module for shelter. Leonov was walking in calf deep sweat still trapped in his space suit from his space walk. Both cosmonauts stripped, removed the liners from their space suits and wring them as dry as possible, then put the on again along with the wolf skin boots and abandoned the useless space suits. The crawled into the landing module for the night, well aware that the taiga was filled with bears and wolves, and that this was mating season, when they were most aggressive.

The hatch was out of reach. The lights failed, but the circulation fan ran all night. The temperature dropped to 22 below zero.

A rescue party arrived on skis the next morning; they chopped trees to build a small log cabin and a big fire. The cosmonauts spent a second night, then skied out to where a second, larger party had chopped down enough trees for a helicopter to land.

I guess they made ‘em tough in those days. I suspect they still do.

625. Gateway Drug

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Science fiction is a gateway drug. I don’t mean a gateway into general reading; that would probably be Dr. Seuss. I mean a gateway drug into a life of exploration.

Harlan Ellison told this story on himself. He was on a tour of some space installation, probably Houston but I can’t be sure. It’s been years since I read the story. One of the pocket protector crowd came up and told Harlan that his stories had been inspirational to his career. In Harlan’s version of the story, he was unimpressed, but he had a carefully crafted curmudgeon persona, so who knows really. He later found out that he had been talking to an astronaut.

Space exploration is taken for granted today. The moon landing happened during my early twenties, but just a dozen years earlier, in the late fifties when I first became fascinated with science fiction, few people believed man would ever leave the earth.

Science fiction people — writers and readers — believed.

Science fiction has been a gateway drug for a very long time. In 1898, 16 year old Robert Goddard, already fascinated by science, turned his attention to space when he read H. G. Wells War of the Worlds.

With little outside help and while enduring the disdain of his colleagues, Goddard invented the liquid fuel rocket, then went on to invent the multi-stage rocket. He received patents for both in 1914 and had actually built and successfully launched a liquid fuel rocket by 1926. He went on to pioneer the use of gyroscopic control of steerable thrust rockets.

Goddard was launched by science fiction, and in turn he launched a whole flotilla of boy scientists building rockets in their basements and flying off to explore space in the science fiction of the twenties and thirties.

NASA’s Goddard Space Flight Center is named after him.

In 1905, in Transylvania (now in Romania) eleven year old Hermann Oberth became fascinated with the works of Jules Verne, particularly From the Earth to the Moon.

Oberth took training in medicine, but spent his spare time conducting experiments in rocketry. He studied physics from 1919, but his dissertation on rocket science was rejected as utopian. He chose to expand his work and publish it privately, saying he would become a great scientist even without a diploma. He was right.

His book, The Rocket into Planetary Space, became a classic. Its publication led to the formation of the VIR (Verein für Raumschiffahrt — Society for Space Travel) a German group which built and launched rockets in the years between the World Wars. Wernher Von Braun became a member. Oberth later became a mentor to Von Braun.

Von Braun’s work led to the V-2, and the V-2 led to every subsequent rocket built by the Americans or the Russians, including the Saturn V. Oberth was in the crowd watching its launch when it carried Apollo 11 to the moon.

Today Nova on PBS is probably the gateway drug for a life of fascination with space, and science fiction as literature has been largely co-opted by the movies. But there is a lot more content in a science fiction novel than Nova or Star Wars can present, and kids are still reading.

The first time a kid comes upon a science fiction idea, no matter what the quality of the work it appears in, that story is the one which counts. It doesn’t matter how many times the idea has been presented in the past, the story you read when you are twelve or thirteen is the one that stirs your juices and sets your neurons into a new pattern.

Maybe someday, some kid will be inspired by one of my books. The odds are against it so late in the history of science fiction, but it’s a comfort to know that it could happen.

611. Living Through History

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I never worked for NASA. I have no actual connection with the space program, but I love it. These days, everybody is talking about the moon landing, but I’m not going to post about it directly. There is no need. I’m no expert, but every real expert left alive will be on your TV.

My connection is personal, and I first wrote about it when this website was new, in October of 2015. I don’t normally like to repeat old posts, but I can’t say it any better.

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It was pledge week at PBS. They ran the biography of Neil Armstrong for the upteenth time. My wife and I watched it for about the third time, and when it was over, she said, “That was my childhood.”

I knew exactly what she meant. She and I were soul mates long before we met. Pardon the corn, but it’s true. She grew up in Michigan and I grew up in Oklahoma; we met in college. But when we were children, we were both science nuts long before Sputnik. We both repeatedly checked out Vinson Brown’s How to Make a Home Nature Museum and followed the instructions. We both checked out books on how to grind the lens on your own reflecting telescope, but neither of us made one because we didn’t have the money to buy the glass blanks.

On October 4, 1957, Russia orbited their first satellite. I was in fifth grade when the teacher went up to the front of the room and wrote Sputnik on the board. She said it meant Earth-moon in Russian. It didn’t, but we knew almost nothing about the Russians then. A few days later, she wheeled a cart into the room. It had beakers beneath, a tiny sink, and a hand pump. Oklahoma schools had instituted science as a middle school and elementary subject for the first time.

I kept track of every satellite we launched and every rocket that blew up on the pad. There were a lot of them. When the Russians launched Muttnik (the nickname was American) I was fascinated to see a living creature in space. All my schoolmates said only the stinking Russians would send a dog up there to die.

I watched the Mercury astronauts first press conference and quickly got to know them all. I was thrilled when Yuri Gagarin orbited the Earth. Everybody wrung their hands because a Russians got there first, but I didn’t care. We were in space — and we meant people, not Americans.

I watched Shepard’s and Grissom’s launches, and cheered when Grissom didn’t go down with his capsule. In Michigan, my future wife was collecting every magazine that covered the Mercury program.

I was at school while John Glenn was in orbit, so I missed something monumental in our family history. My father, who thought the space program was a waste of money, got off his tractor and came in to watch the televised coverage. He later said, “I just couldn’t work until we got that old boy back safe.”

The rest of Mercury, Gemini, the beginnings of Apollo — I followed every mission.

I had discovered ecology, at a time when nobody knew what the word meant. I spent my junior year building an Ecosystem Operable in Weightlessness for the regional science fair. It was complicated, cutting edge, and more than I could actually complete by fair day. I won’t bore you with the details, but it helped get me a Fleming Fellowship the following summer. That gave me a chance to work with real scientists and to see some of the world beyond my tiny town. Those were the people who suggested I should apply to Michigan State.

At MSU the Biology department cared nothing about ecology. I was a few years too early; if you didn’t need an electron microscope to see something, it wasn’t interesting — to them. The closest thing to behavioral biology was Anthropology, and that is where I ended up. And where I found my wife.

We married in 1969 and took off for a long drive around the US, visiting relatives and national parks. We got back to to East Lansing in mid-July, following Apollo 11 on the car radio. On July 20 went went in to the student lounge of her old dorm and sat with dozens of college students watching a grainy black and white TV as Neil Armstrong set his foot on the moon.

You should have been there.

595. Apollo 10

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Apollo 10 CSM, viewed from the LEM in lunar orbit.

Apollo 10 is a mission that, from the outside, looks unnecessary. It was anything but that. To appreciate it, you have to project yourself back into the state of ignorance that represented best knowledge in 1969.

I was also guilty of underrating it when I taught middle school science. I called it the most frustrating flight in the history of space flight, which was half true and half exaggeration. I also called the Command Module Pilots NASA’s soccer moms because they got to go to the game, but never got to play.

You have to know your audience, and middle school kids are looking for excitement, not “slow and steady wins the race”. And certainly not “they also serve who only stand and wait.”

In actual fact, without Apollo 10, the would have been no moon landings. There were two basic reasons for this. The LEM had only been tested in low earth orbit, not falling into a gravity well and then clawing its way out again. And we had an entirely inadequate understanding of the conditions on the ground at the proposed landing site. We especially needed to fine tune our understanding of lunar gravity for navigation purposes.

As the NASA history website puts it, “a test of the landing radar, visual observation of lunar lighting, stereoscopic strip photography, and execution of the phasing maneuver using the descent engine” were all performed on Apollo 10’s pass over the proposed landing site. If you want more data, check also here.

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On May 18, 1969 Apollo 10 lifted off from Cape Canaveral on its way to the moon. Thomas Stafford was Commander, John Young was Command Module Pilot, and Gene Cernan was LEM Pilot. They entered orbit of the moon three days later. Stafford and Cernan undocked the LEM and began their descent fifty years ago today.

John Young was left alone in the Command Module, the first of seven men who would fly around the moon solo while their companions dropped toward the moon’s surface.

Stafford and Cernan fired the descent stage engine to slow the LEM. There followed a long unpowered descent, a rapid flyby of the proposed landing site, and a rise back up to the level of the CSM.

The reports at the time called it a dress rehearsal for Apollo 11, but it wasn’t that simple.

For comparison let’s look at a mission designed to land. At point A on the figure given here, the descent stage engine would fire briefly, changing from the black orbital path to the green one. At point B, a carefully calculated spot nearly half way around the moon, the descent engine would fire again. The descent from 60 miles to about 8 miles would have been in a flat curve, followed now by a very steep curve. The descent engine would continue to fire until the vehicle landed at point C. This is basically the exact reverse of a launch, as shown Monday.

Later, the ascent stage engine would fire, leaving the descent stage on the moon’s surface, and proceed along the second half of the green curve back up to the 60 mile level.

Apollo 10 (red orbit), on the other hand, passed over the prospective landing site and continued on.

This has always been called a dress rehearsal, so one would assume that the ascent stage would separate somewhere near the surface, fire its engines, and continue back up toward rendezvous separately from the descent stage. That’s what I thought for fifty years.

I was wrong. Imagine that. I probably learn more researching these posts than anyone does who reads them.

In fact, on Apollo 10 the descent stage fired again at point D (the red orbit represents Apollo 10), but it was merely a course correction, and the entire LEM continued up to the 60 mile level.

Apollo 11 would leave from the moon’s surface, starting at zero speed. Apollo 10 at its lowest point was at an altitude of 8 miles and a speed of 3554 miles per hour. Dress rehearsal was a considerable exaggeration. It wasn’t that reports were inaccurate; things were just more complicated than the summaries suggested.

It’s a little like science fiction novels. A two line blurb on the back of a 180 page paperback may not actually lie, but it can certainly give a false impression.

At point A on the trip back up for both missions another burn was necessary to get back onto the black curve. However, the CSM had gone its own way; it wasn’t waiting there for the LEM. The final rendezvous for the LEM and the CSM, which were at different places on roughly the same orbit, would be up to the pilot of the ascent stage, and would take an additional three hours.

At this point on all the moon landing missions, the ascent stage would be by itself. For Apollo 10, the ascent stage still needed to separate from the descent stage before performing the orbital insertion burn using its own engine.

That was the plan, but things didn’t entirely go well. Just before the separation, the LEM began acting up, corrected itself, then seconds later started a rapid roll. It was later determined that this was due to erroneous computer input. Stafford and Cernan quickly separated and regained control, but it was another of those close calls which could easily have led to a deadly outcome.

The crew rendezvoused and docked with the CSM, then returned to Earth. The ascent stage engine was fired again and went into solar orbit. The necessary data had been obtained for the moon landing in July.

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At present, I plan for this to be my last full Apollo mission post. Everybody will cover the anniversary of Apollo 11. Everybody has already watched the movie Apollo 13, and I covered the other landings in 187. The Rest of the Landings. Of course, I reserve the right to change my mind.

594. Into Orbit

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Fifty years ago last Saturday, Apollo 10 left for the moon. As you read this, depending when you click in, they are/were part way there. The mission’s big events will have their anniversary Wednesday, and that is when the main post will come.

Meanwhile . . .

From the fifties onward, there were dozens of books by people like Arthur C. Clarke and Wily Ley that explained in great detail how  we would go to space. I read most of them — at least every one I could get my hands on. There were a lot of people like me then. A lot of them spent the last decades working for NASA.

Now our knowledge of the universe is vastly greater, and most kids today know more than the best informed knew then. Still, some basic things get missed, because “everybody already knows them”.

Actually, they don’t. Here is an example, which I need to get out of the way before I talk about Apollo 10 on Wednesday.

Imagine, a rocket leaves Cape Canaveral with rocket engines flaming. The engines only burn for a  fairly short time, for reasons of efficiency; then the rocket coasts upward into orbit.

Right. And wrong. There is one more important thing that happens, but rarely get mentioned any more. A second critical burn has to happen at the high point of the initial orbit (apogee).

A rocket heading for orbit leaves the pad vertically, but it immediately begins to roll over. It needs to gain altitude to get above the atmosphere, but it also needs to gain velocity horizontally, so its upward path is a precisely programmed curve that begins vertically and ends horizontally (i.e. tangent to the surface of the Earth). This tangent is reached long after the rockets have ceased firing, at apogee, roughly half way around the Earth.

Caveat: everything in orbital mechanics is more complicated that the explanation you will get from someone like me. Nevertheless, this should be close enough for our purposes.

Let’s assume that the orbital insertion burn did not happen at apogee. Our craft would have achieved enough speed to reach its orbital altitude, but not enough speed to remain there. It would immediately begin to descend.

Think of a high fly ball to center field — up, then down again. Same Earth, same gravity, same result.

Such a rocket leaving Earth would burn up on reentry. If it were launched from an airless body like the moon, it would end up in an elliptical orbit with its low point very near the surface.

Instead, if all went well and the secondary burn took place when the rocket had reached its orbital altitude, it would change from a sharply elliptical orbit to a more nearly circular one. This is the normal way things get done.

You’ll need to have this in mind when we look at Apollo 10’s “dress rehearsal” on Wednesday.

586. Slogging Toward Space

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One of the things I have to offer is a viewpoint that reaches back half way through the twentieth century. That can be a problem, actually. I don’t want to talk about the good old days. Fortunately, I never thought the good old days were all that good. They were, however, both exciting and hard.

It has become almost cliché to point out how little computing power the Apollo 11 computer had, but there are a thousand other instruments which we take for granted now, which were also not available during the early space program. I used a few of them myself, early on.

Some of these instruments became fossilized into early science fiction, as in Slip-stick Libby, one of Heinlein’s regular characters. Slip-stick was a slang term for a slide rule, an instrument of sliding scales which was used in computation. It was only good for estimating to about three significant figures. I learned to use one in high school in 1966. Early Texas Instrument portable calculators made them obsolete a few years later, although you will still see them in use at Mission Control when things began to go bad in the movie Apollo 13.

Another nearly obsolete instrument from the Apollo era is the theodolite. I learned to use one in the same class. We took it out to the back lot of the school for some practical examples of the uses of trigonometry. We didn’t call it a theodolite, however. We called it a transit, which is somewhat less accurate. Real surveyors called it a gun.

A transit measures elevations and angles. You level the instrument on its tripod and align it to true north, then you look through a telescopic sight, with crosshairs, at a distant target, usually a rod with red and white inch markings.

(We’re talking sixties here — everything in America was in inches, feet, and miles.)

This instrument was used in surveying everything from house foundations to radar installations before lasers replaced them. It gave you direction. It didn’t give you distance. For that you walked, dragging a measuring device called a chain.

The dictionary will tell you that a chain is a unit of length equal to 66 feet, subdivided into 100 links. It may not tell you that a chain (of length) was represented by a heavy, physical, steel chain that the rod man dragged behind him — for thousands of miles during a career.

Today, laser radar does it all.

An alidade or plane table worked like a transit except that it was attached to a narrow steel plate which moved freely on a plywood table. It was used for mapping. You would slide the alidade around on the table, over a sheet of paper, take your sightings, and use the edge of its base as a ruler. It allowed you to  draw a map as you went. I used one of them two years after high school at an archaeological site in Bay City, Michigan.

To fully understand what a tremendous undertaking the space program was, you should remember that a line of radio/radar stations was built all around the world to track spacecraft in orbit. At the same time, the same Russian missiles which scared American into the space race had to be watched for. A line of radar installations (the DEW — distant early warning — line) was built across Canada for that purpose.

The building of these two sets of installations was an immense undertaking. Even before the first foundation was laid, the positioning of these instruments had to be determined to the highest possible tolerances. This was done by survey engineers working with transits and doing their calculations by hand, with rod men dragging chains. A slide rule might provide estimates, but after that it was paper, pencil, and mathematical tables — which had themselves been calculated by hand.

The word calculator first meant a person who calculated such tables. By hand.

These engineers didn’t all come from Harvard, or other prestige colleges. There were thousands of them, possibly tens of thousands, and they came from every college in America. Bear that in mind as we contemplate the present college entry cheating scandals.

Speaking of which — prestige colleges my &#^$%!  Math is math, whether you learn it at USC or Palomar Junior College.

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I want to introduce you to a survey engineer you have never heard of. He is a distant in-law, a fine man I only met once. I ran across a decades old newspaper clipping of his obituary the other day, and it triggered this post.

I’m appending a copy of that clipping, minus family matters, to give you an idea of how the space race, and the missile defense of America, looked from the mud below. The gentleman’s name was William Mussetter.

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Mr. Mussetter graduated from Willmington College in 1917 and also attended Haverford College in Haverford, Pa. He retired after working 40 years in government service as an astronomical geodetic engineer. He served with the US Coast and Geodetic Survey, Army Map Services, InterAmerican Geodetic Survey United States Department of Foreign Services where he worked in many different countries.

Mr. Mussetter was a veteran of World War I, serving as a second lieutenant. In World War II he served as a captain and taught artillery.

At the end of the World War II, Mussetter received a call from Washington, D. C. He was assigned to head a survey group to be based in Panama and to work in south America, principally on the west coast of Chile, Peru, Ecuador, Columbia to Venezuela. This project lasted four years.

The Mussetters came home to Wilmington and he worked with the Ohio State University doing contract research for the U.S. Air Force. There was a need to connect the continents of the world, locating them with respect to each other, then to lay out guided missile courses from Cape Canaveral to the Bahamas. [This means during the early testing of IRBMs and ICBMs, before they began to be used to launch space vehicles. The same tracks were used through Mercury, Gemini, and Apollo. See 578. That Odd Spiral.]

In 1953, he transferred to the U.S. Army Corps of Engineers to define the Earth’s parameters, its diameters, flatness at the Poles and other data. [We are talking about building the DEW line here.]

He worked with a survey team measuring the arc of the Meridian at 30 degrees East Longitude from the Mediterranean Sea at Egypt to South Africa, down through Egypt, the Sudan, Uganda, Belgian Congo, Tanganyika, and into North Rhodesia; 4800 miles. [Many of these names no longer exist.] He also did some survey work for the Aswan Dam on the Nile River.

In 1964 he was sent to Antarctica, to Byrd Station, and the South Pole.

He had retired in 1964, but during the last four months of 1964, he worked in Peru, S. A. on a contract for a hydro-electric project; and in 1966 he was sent back to Afghanistan for three months, to inspect the work that was begun in 1961, and complete the Tri-lateration of Afghanistan.

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All this without a computer. Imagine that.

578. That Odd Spiral

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This is the track of Sputnik, the first satellite launched from Baikonur Cosmodrome at latitude 46 degrees north. Launches from Cape Canaveral followed paths that were more flattened out because they were launched from 28 degrees north.

The orbital path shown above was to be found in thousands of publications at the dawn of the space age. Everyone carried the image in their heads, but today I had a hard time finding it on the web. My how times change.

Every space geek in 1960 would have known everything in this post, but then Star Trek came along. Kirk and Spock, and especially Uhura, went at warp speed and walked around on the floor like it was a sound stage in Hollywood. No weightlessness there. Then Star Wars came along and all veracity went out the viewplate.

There were a lot of very basic principles of physics that governed the space program, which Hollywood had to ignore.

Let’s begin on the ground. The Earth rotates eastward at a certain number of miles per hour. (We are channeling 1960 here. None of the published reports on space used the metric system back then.) Any geek with a pencil could figure out rotational speed by dividing equatorial circumference (25,000 miles to any 1960’s space fan, forget the decimals.) by the length of the day. !042 miles per hour eastward at the equator.

A spacecraft in low Earth orbit flies at 17,500 miles per hour. Actually that varies, but that was the figure in all the space enthusiasts books at the time. If you launched a rocket eastward, you started with about 1000 mph of free speed. If you launched westward, it would cost you 2000 mph of extra speed. You wouldn’t gain the natural advantage, and the rocket would be going 1000 mph the wrong way as it sat on the ground.

Everyone launched eastward.

There was actually another reasonable option, launch north or south. We’ll look at that choice at the bottom of the post.

Actually you don’t get all of that speed advantage. The circumference of the Earth is less as you move northward, lowering the eastward speed. If a United World wanted to choose the most advantageous place for a spaceport, it would be at high altitude somewhere on the equator. That happened frequently in science fiction.

Neither America nor Russia had a far southern point suitable for a space port. America’s best choices were Texas and Florida — the same two states Jules Verne pointed out in From the Earth to the Moon. Florida had the added advantage of having the Atlantic ocean to eastward, which provided a place to drop first stages and failed rockets, without landing on anybody’s house.

Russia built in the desert at the same latitude as Portland, Oregon, but they always chose secrecy over other factors.

Launching eastward is an exaggeration, of course. Straight east from either site won’t work; launches had to be aimed south of east to bring the center of the orbit into line with the center of the Earth’s gravity.

You might think that a launch from Canaveral would return to Canaveral after one orbit, but that isn’t true. The Earth is rotating eastward, so a spacecraft launched from Canaveral will pass over a spot about a thousand miles west of Canaveral on its first return. And so forth. Which is why the cosmonauts were a thousand miles off target after one extra orbit in yesterday’s post.

All this gives us that odd spiral at the top of the post.

In fact, you could launch a spacecraft into orbit from any point on Earth as long as its orbital path circled around the Earth’s center of gravity. Further south is simply more efficient.

You could even launch satellites due north, and we do, from Vandenberg Air Force Base on the west coast of California. Such satellites also spiral around the Earth, but they cover every part of the Earth eventually. Weather and spy satellites use this orbit.

Southeastward launches from Canaveral and Baikonur don’t cross over the far north or the far south.

What about a satellite exactly circling the equator? In low Earth orbit, it would circle the Earth about every 90 minutes. The moon, a quarter of a million miles further out, circles the Earth in 29 1/2 days. Clearly, even for math challenged enthusiasts, the further out the satellite, the slower it travels in orbit. At some distance from the center of the Earth, it would take a satellite one day to circle the Earth. Seen from Earth, it would appear to hang in one spot above the equator.

Everybody should know that, because that is how communication satellites work. The first person to recognize the fact and calculate the distance was Arthur C. Clarke, known even to non-SF readers from 2001, a Space Odyssey. The connection between science and science fiction has always been close.

577. The First Space Walk (2)

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The space suit worn by Alexei Leonov on the first human space walk. On display at the Smithsonian National Air and Space Museum. Author: Nijuuf

This is the rest of Tuesday’s post. If you haven’t read it yet, take the time to do so, or this won’t make much sense.

Alexey Leonov had extreme difficulty reentering the airlock. His space suit had over inflated; the boots and gloves had slipped beyond his toes and fingertips, and his suit had increased in girth. He had to vent part of his rapidly depleting oxygen in order to bring his suit down in size, and even then he entered the airlock head first, instead of feet first as planned. Once inside the airlock, he had extreme difficulty contorting his body to close the outer door. All this time, his body was heating up dangerously; surrounded by vacuum, there was nothing to carry away the heat his body was generating.

Once air pressure had been restored in the airlock, Belyayev opened the inner door and Leonov was safe. For the moment. As he said in an article for Smithsonian’s Air and Space magazine in 2005, “the difficulties I experienced reentering the spacecraft were just the start of a series of dire emergencies that almost cost us our lives.”

The mission had achieved it’s goal and it was time to return, but just before the scheduled time for firing retro rockets the cosmonauts discovered that their automatic guidance system was malfunctioning. It took time to prepare for manual entry, so they had to wait one orbit, which would make them miss their return point by a thousand miles. (To find out why it would be a thousand miles, see the post coming on March 25.) Most of that orbit they were out of radio communications. (The Americans had built a string of radio relay stations around the world to maintain constant communication with their astronauts, but the Soviets had not.)

When communications were restored, ground control asked them where they had landed.

Their orbital path was set; the moment of firing their retro rockets would determine where on that orbit they would land. They chose a target just past the Urals. Using the clumsy and difficult manual backup equipment, they achieved the correct attitude and fired the retro rockets in the conical rear portion of the craft called the orbital module. The orbital and landing modules were supposed to separate ten seconds after retrofire. They didn’t.

The two cosmonauts knew immediately that something was terribly wrong. Instead of the steady press of force against their backs as they decelerated, they found themselves whipped about by confused forces that exceeded ten gravities. A communication cable between the two modules had failed to release, and now both modules were whipping about each other, tethered by the cable.

Finally, about 60 miles up, the cable burned through and the cosmonauts were freed. The drogue chute deployed, and then the main. All was peaceful and in order – briefly. Then it became dark as they dropped below cloud cover, the final rocket fired to slow them to landing speed, and they touched down in six feet of snow.

They were 1200 miles beyond their intended landing point.

They blew the explosive bolts to release the hatch. It didn’t open. They had landed in the middle of a forest and the hatch was held shut by a tree. By yanking violently they dislodged it and it fell away, lost in the snow.

They made their way out of the spacecraft and waded through snow to a small clearing. Those back at headquarters had not heard their landing signal, but a passing cargo plane had. It circled, and was soon joined by other planes and helicopters, but none of them could land in the rough taiga. Pilots threw a bottle of cognac; it broke. They threw warm clothing which got caught in the trees, but at least two pairs of wolfskin boots made it to the ground.

The light was failing. The cosmonauts returned to their craft for shelter. Leonov was walking in calf deep sweat still trapped in his space suit from his space walk. Both cosmonauts stripped, removed the liners from their space suits and wrung them dry, then put the on again along with the wolf skin boots. They abandoned the useless space suits and crawled into the landing module for the night, well aware that the taiga was filled with bears and wolves, and that this was mating season, when they were most aggressive.

The hatch was out of reach. The lights failed, but the circulation fan ran all night, adding to their misery. The temperature dropped to 22 below zero.

A rescue party arrived on skis the next morning; they chopped trees to build a small log cabin and a big fire. The cosmonauts spent a second night, then skied out to where a second, larger party had chopped down enough trees for a helicopter to land.

I guess they made ‘em tough in those days. I suspect they still do.