Tag Archives: americana

570. Lunar Excursion Module

This is the Apollo 9 LEM, photographed after it separated from its CSM. Photographs of either CSMs or LEMs in space are typically nose on, since each could only be photographed from the other (there wasn’t anyone else around to do it), and they only separated in lunar orbit at the outset of a landing maneuver or at rendezvous. Apollo 9 separated in low earth orbit and performed various maneuvers there, making this side-on view, right above the Earth, a rare treat.

Apollo 9 launched fifty years ago March third. That’s a Sunday, and I don’t post on Sunday, but there will be plenty on that mission the following week.

Virtually all of the missions returning from space have returned by atmospheric braking and parachute, or atmospheric braking followed by a winged landing. In the early days of science fiction movies, landings were always tail first but that was not possible on Earth until Elon Musk and SpaceX finally managed it in 2015.

On the moon, there was no choice but to land tail first, slowed by rockets, and the LEM was built around that fact. Learning how to land tail first was also a major issue; see 185. The Flying Bedstead.

The LEM was a two stage rocket. The descent stage, dot-shaded gray in this NASA drawing, made up about two thirds of the mass of the LEM. It contained a frame, tanks with fuel and oxidizer, a rocket engine, and the landing gear. It also contained storage space, accessed from the outside, for the equipment that would be used once the astronauts were on the moon.

The landing gear served multiple functions. The pads at the end of each leg were designed to keep the LEM from sinking into the lunar soil. Their size was both a compromise and a guess. No one knew either how deep the lunar dust was, nor how much structural integrity it had. Worst case scenarios had the LEM sinking hopelessly into many feet of lunar dust, the accumulation of millions of years of micrometeorites pulverizing the lunar surface. In fact, the pads only sank slightly.

The number of unknowns that faced the engineers and mission planners was immense. It it hard for people born since the seventies to imagine the depth of our ignorance before Apollo 11 landed.

The struts were designed to absorb energy, because the LEM could not fire its engines all the way to the ground. The upwash of lunar dust and rocks would have blinded the pilot and possibly knocked holes in the LEM, so the engine was designed to be cut off at a certain height above the lunar surface, letting the LEM fall the last small distance. But how high? That was another calculated estimation (guess). And how much spring would the struts need? Too little and the LEM would crash to the ground. Too much, and it would rebound with possibly disastrous results. And if one leg landed on a boulder or in a hole, the whole LEM might tip over and be unable to return to orbit.

The ascent stage contained crew space, controls, computer, radar, guidance systems, oxygen for human use, and the crew in their space suits. It also contained fuel and oxidizer and its own rocket engine, all smaller than for the descent stage since the LEM ascent stage was one third the size and mass of the complete LEM. The descent stage formed a launching platform for the ascent stage.

When Apollo 17 launched from the moon, a camera was mounted on the rover which was left behind. You can see all 36 seconds of the last ascent stage liftoff from the moon at https://www.youtube.com/watch?v=9HQfauGJaTs.

Apollo 11 proved that all this would work. Apollo 10 was a dress rehearsal of everything but the final landing. But until Apollo 9, fifty years ago this weekend, no one knew if the LEM would work at all.

More next week.

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569. Apollo: Profile of a Mission

This is the Apollo 9 LEM, photographed after it separated from its CSM. NASA photograph.

This was originally intended as a detailed picture of the Lunar Excursion Module, but it became clear while writing that before I could talk about the vehicle, I had to lay out it’s place in the scheme of things. This post then became a generic mission profile, and details of how the LEM worked will come in the next post.

If you Google lunar lander, you will find the LEM, but you will also find a lot of forgotten craft. Both the United States and the Russians had unmanned lunar landers and lunar crashers. That’s not a joke. Before soft landing was perfected, we learned a lot about the moon from probes which photographed all the way down to a crash landing. Those piles of rubble that dot the moon were the ancestors of Spirit and Opportunity.

That’s not good enough for a craft that was to be, in the vernacular of the day, man rated.

The LEM, or LM as it is often called today, was unlike any manned craft before or since. It has been called a “true” spacecraft, but in fact it only got half way toward that ideal. A “true” spacecraft, built in space and powered by a low force, long acting engine, would never have to endure the vicissitudes of atmospheric friction or high gravity.

The LEM did have to withstand multiple gravities during its launch from Earth, and again on landing and taking off from the moon. However, it never had to come in contact with atmospheric friction because it spent the launch hidden behind a streamlined clamshell shroud. It didn’t itself have to be streamlined, and its skin could be flimsy. The astronauts joked about being afraid of accidentally putting a boot through the side of the vessel. At least I think it was a joke.

The Saturn 5 is called a three stage rocket. It could as easily and accurately be called a six stage rocket. The first and second stages were designed to burn all their fuel and fall away. The third stage carried the rest of the vehicle into orbit and then shut down; at that point, it’s fuel was not exhausted.

If the mission was to lunar orbit or landing, the Apollo craft stayed in low earth orbit long enough to establish that all was well, then the third stage fired again to send the craft toward the moon.

On Apollo 8, there was no LEM, so in December I only described the Saturn and the CSM. Apollo 9, whose fiftieth anniversary comes in about ten days, had a LEM but never left near Earth orbit. Apollos 10 through 17 were lunar missions. They had similar flight plans and used all “six” stages.

When the Saturn third stage fired a second time, it put the entire remaining craft into a orbit toward the moon. The third stage would have gone right along with the rest to the craft, if it had been allowed to do so.

What happened next on each mission was well presented in the movie Apollo 13, but only if you already knew the what, the when, and the why. It was drama, not documentary, but with excellent animation. If you have a DVD of Apollo 13, take a look.

The LEM, and the CSM (command and service modules, treated as one) had initially been stacked vertically above the third stage, with the LEM protected by a shroud. The attached NASA drawing also shows the abort rocket above the command module, but that had already been discarded by the time the craft was actually on its way to the moon. All three astronauts were in the CM. The CSM, the LEM, the shroud, and the third stage are all still in one piece.

Now the CSM was released; it moved forward on maneuvering thrusters and turned a one-eighty. The LEM was still attached to the third stage. Now the clamshell opened up and the CSM moved carefully forward and docked with the LEM, front of CSM to top of LEM. The LEM was released from the third stage and towed away by the CSM. This position allowed the hatches on the CSM and LEM to mate so the astronauts could move freely between the two craft. The legs of the LEM, previously tucked under to fit within the shroud, now extended into lunar landing positions.

From this moment until lunar orbit was achieved and it was time for the LEM to move away from the CSM and land (or nearly land in the case of Apollo 10), the LEM/CSM were essentially one space craft. The Saturn third stage now made one last burn, changing to an orbit that would carry it out of the way.

For about two and one half days, the LEM/CSM drifted toward the moon. Upon leaving low Earth orbit, the craft had been traveling at close to 25,000 miles per hour. It should have reached the moon in ten hours, but the Earth’s gravity was pulling at it and slowing it down. Approximately six sevenths of the way to the moon, the craft was traveling at it’s slowest speed. At this point the Earth’s gravity and the moon’s gravity were in equipoise; thereafter the moon’s gravity accelerated the craft again.

At a point on the back side of the moon, the SM engine fired, slowing the combined craft enough to keep it from whipping around the moon and returning to Earth. It entered orbit of the moon. This burn, and the later one which put the CSM on its homeward trajectory, make the CSM essentially the fourth stage of the Apollo/Saturn mission.

Now it was time for the LEM to earn its keep.

What’s that you ask? Stages five and six? Where were they? The LEM itself was a two stage rocket. We’ll get details on that next post.

568. Presidents Day

I agonized over this post more than any in memory. I am not completely cynical, and the presidents I address, even the worst of them, also did things worthy of the office. I came back to this post a dozen times after I wrote it to ask myself, “Do I really want to say these things?” The answer is, “No.” But I will say them anyway, because the truth is the truth.

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Presidents Day. Humm.

We used to celebrate Lincoln’s birthday and Washington’s birthday, and ignored the rest of them. That wasn’t such a bad system. It allowed us to avoid linking Andrew Jackson with his betters.

How about our recent Presidents? Should we celebrate them?

John Kennedy. I have a friend who grew up in Boston and would punch out anyone who spoke against JFK, but let’s tally up what he really did. He lost the Bay of Pigs by abandoning the Cuban insurgents he had encouraged. He faced Khruschchev over the Cuban Missile crisis so let’s give credit for that, but he also sent Americans to Vietnam. Kennedy supporters claim he would have pulled out, if he had lived, but who knows. The jury will always be out of what might have happened.

Lyndon Johnson. He has massive accomplishments pushing through Kennedy’s programs and his own War on Poverty, but he also lied to the American people, lied to Congress, and conducted a secret war including massive bombings outside Vietnam. He, and Nixon after him, are responsible for over three million unnecessary  deaths. There is no responsible way to avoid calling him a war criminal.

Richard Nixon. Watergate, of course; it hardly needs repeating. He also opened up China and got us out of Vietnam by declaring that our defeat was a victory, and then running like hell. I really don’t know what else anyone could have done by that time, but why did he wait all those years and waste all those lives before telling the Big Lie? Maybe to win a second term.

Gerald Ford. They say his pardon saved the country from division and heartache. I say it only gave later Presidents bad ideas that should have been squelched fifty years ago by trying Nixon for his crimes.

Jimmy Carter. An attack on an embassy is an attack on American soil, but Carter sat impotent in the White House through the Iran hostage crisis.

Ronald Reagan. Tax cuts for the wealthy. Trickle down economics that never trickled down. Also the Iran-Contra affair in which Regan himself avoided punishment but fourteen members of his administration were indicted.

George H. W. Bush. “Read my lips.” Actually, going back on his promise regarding taxes was an act of courage that probably cost him a second term. That honorable act was sullied when he pardoned those convicted in Iran-Contra.

Bill Clinton. Plenty of good ideas, but we just remember him as the man who couldn’t keep his hands to himself.

George W. Bush. “Brownie, you’re doing a heck of a job”, and other stumble-statements too numerous to list and too painful to remember.

Barack Obama. I like the man, but I spend eight years cussing under my breath at some of the foolish things he did.

Donald Trump. I once said I didn’t consider Trump evil, just foolish. Subsequent events suggest that I was probably wrong. His fake declaration of emergency pretty much clinches matters.

Were these the best men in America?

Let’s celebrate President’s Day by taking a hard look at what’s coming our way in 2020. They don’t all look good. Let’s vow to make better choices for the future.

Lincoln and Washington, where are you?

565. Great (?) Men

This post was begun December 5, 2018, before the shutdown, right after watching President Bush’s funeral. Most of the posts from that time until now were already written to make time for some non-writing activities, so I watched the Federal shut-down from the sidelines. I will summarize my take in one sentence.

Another damn-fool stunt by the Damn-Fool-in-Chief.

Now back to December fifth.

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As I watched President Bush’s funeral this morning, I was once again struck by an understanding of how Trump became president. I am not going to offer similarities between the two men; I would be hard pressed to find any. I will suggest instead that the nation’s response to Bush One’s death tells us uncomfortable things about hero worship, individual liberty and responsibility, and America’s closet love affair with The Great Man.

America threw off a king in 1776, and has been in the habit of electing would-be kings to the presidency ever since.  They even asked George Washington to become king. He refused. If there has been a president since who didn’t want the powers of a king, I apologize for lumping him in with the rest. I don’t think I will have to apologize to many. Maybe none.

I get that. I also get that without a combination of arrogance and obstinance, and a massive need for power, no candidate would ever get through a campaign. Obama strikes me as a nice guy, someone I would like to know personally, but he had the need. Bush II was touted as the candidate you would most like to have a beer with — and I would, even though I never considered him competent. Vote for Bush II, hell no; share a laugh with him, of course. Bush II had the need. Bush I had the need. They all had the need for power.

You can be pretty sure that any humility shown by any president is feigned. Was Lincoln humble? He appeared humble, but I seriously doubt that he was. Overwhelmed and saddened by what fate had saddled him with, certainly, but a truly humble man would have withdrawn in favor of someone more qualified.

But Presidents don’t believe anyone else could be more qualified; if they did, they would never make it to the White House.

I understand the motivation of Great (?) Men; I don’t really understand why Americans, who otherwise cling to their liberties, continue electing them. Perhaps they are convinced that the alternative to the Great (?) Man is the wimp. Or maybe it’s just the John Wayne syndrome gone wrong.

Here’s what happens. There is trouble in the town. Every man knows what needs to be done. But only one man has the fastest gun and the toughest fists. So (the Lone Ranger) (John Wayne) (Chuck Norris) (millennials, fill in your own selection, I’m out of touch with current heroes) takes care of business because he is The Great Man.

That’s adequate for TV, but not for governing America. Presidential power has been growing at Congressional expense for several decades. Why? Maybe at the core it is because the President is one man and Congress is many. Is it just part of the American myth that the individual stands up to the mob?

Maybe.

I get it — but I don’t buy it.

560. We All Learn

Race has a persistent and powerful influence on America for something that really doesn’t exist.

Take the whitest non-albino in America and stand him on the western border of Kansas. Take the blackest black in America and stand him on the eastern border of Kansas. Now line up all the rest of us in a single line, whitest to blackest, in between those two. There would be no break in the continuum.

That should be no surprise to anyone. We have had black slaves (and their descendants) and white immigrants in America rubbing up against one another for four hundred years.

For four hundred years, white DNA patterns have been entering black America through force and black DNA patterns have been entering white America by passing. Lately, that DNA has been going both directions for kinder, gentler reasons.

It’s all been a giant blender — powered at first by hatred and eventually by love —- mixing up the vanilla with the chocolate. There is no use pretending that we are two races any more.

Right!

Try telling that to a white guy. Or try telling it to a black guy.

Clearly, there’s more to the story.

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When I was growing up in rural Oklahoma in the fifties, the idea of two separate races seemed real and normal, but theoretical.

In my small town and the countryside around there were no black folks. Also no Jews. Nor Mexicans. No Italians either, come to think of it. There was one Catholic family who lived there briefly, but they didn’t last.

It was white, white, white, and Protestant, for as far as the eye could see, with one exception, —— Eddie. I’ll leave it to you to guess what word went into the blank; hint, it began with “N”.

The gentleman didn’t live in my community, but we saw him driving by in his pickup from time to time. He lived somewhere north; I never knew where. I never met him. I only knew him as a blurred, black face in a passing vehicle.

All the adults knew him and spoke well of him. He minded his own business; he took care of his family; he was a good farmer (wherever his farm was); he was quiet and he went his own way.

Now, if I weren’t talking about race, that would sound like a description of The Quiet Man. The archetype. The lone cowboy who rides into town, minds his own business and bothers no one. But don’t cross him because he takes no guff from anybody.

Nope, that’s not it at all. Not even close. But take away the last sentence — the one about “don’t cross him” — and change it to “gives no offense to anyone but quietly backs away”. Now you are closer to the truth. You have just defined the difference between The Quiet Man and Uncle Tom.

The Quiet Man knows his worth; Uncle Tom knows his place. Even growing up in whiteland, with no blacks around, I knew the difference.

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In my childhood, the only black folks I saw other than a blur on the highway, were on television. They were marching in Selma and across the South. And yes, now we are getting to why this post is coming on Martin Luther King Day.

My father called them troublemakers. He liked the phrase “outside agitators”, as well. I disagreed. I looked at the black people being washed down southern streets by fire hoses and said, “They’re right. We’re wrong.”

I didn’t say it out loud. I didn’t say much of anything out loud in those days except, “Yes, sir.” But a few years later when I escaped to college, I had decided for myself that black folks were as good as I was.

Now that may seem a rather obvious decision to you, but a lot of people from my generation and the one that followed never got the message. You see a lot of them now at rallies for a certain orange faced politician.

Martin Luther King and the tens of thousands he represented showed me an alternative to my father’s thinking. I thank them for giving me another option.

555. Calf Quilt

So what, you may ask, is a quilt doing in a writing post?

No writer just writes. My wife and I both discovered quilting in the mid-eighties. For me, it was an art form in which I could satisfy myself. My painting always lacked something, to my eye, but quilts are colorful geometric things with utility. I could make a quilt and not feel artistically inadequate.

For about a decade we have been deeply involved in putting together a quilt show for my wife’s guild every other year. In 2017 I took some time off from this blog, and I may have to do so again this year.

All this is simply to point out that if posts get scarce this month, nothing is wrong. I am just busy with a different piece of my life.

552. Links to Christmas

Tomorrow is the big day, when nobody should be on the internet, so I’ll have my say today. This is the fourth Christmas season since I began this website, and every year I say the same thing. I love Christmas.

I stand with Dickens, who called Christmas “a good time; a kind and forgiving, charitable, pleasant time; the only time I know of, in the long calendar of the year, when men and women seem by one consent to open their shut-up hearts freely.”

Over the years, I have posted many Christmas or Midwinter posts. If you are new to this site, here’s your chance to check some of them out.

My first year I posted a list of Christmas books, covering pretty much every aspect of the holiday. That same year, I talked about Dickens’s five Christmas novellas. Everybody knows A Christmas Carol; here is your chance to check out the rest.

When the ghost of Christmas Past appeared, Scrooge asked, “Long past?” and was told that she meant his past. My own early Christmases on the farm wouldn’t make a Christmas card, but I told about them in Twas the Season, posts 1 and also 2. I also talked about the Nostalgia for those days that never were .

Everyone talks about Mary and Jesus, but what about Jesus and Joseph?

Christmas itself has a history beyond the biblical story. It has always fascinated me, and I summarized what I have learned in three posts from 2016, Old European Christmas, Colonial Christmas, and Here Comes Santa Claus.

In 2016 and 2017, Christmas was overshadowed for my Latin friends by a grinch with an orange face and wild yellow hair. I wrote about Christmas for Lupe two years ago and about Jose, Maria, y Jesus in Trumpland last year. I didn’t have the heart to tackle the current occupant one more time this year. Maybe by next year I won’t need to.

Anyway, whether you check out any of these links or not, Merry Christmas.