Saturday, July 16, 2016

Perspective


My heart goes out to the many people who have been injured or lost loved ones in terrorist actions around the world, most recently the horrific Bastille Day truck attack in Nice, France. These actions are unconscionable and the people who perpetrate or support such acts must be brought to justice.  Terrorism is obviously intended to terrorize, and these attacks are certainly scary, with the scariness amplified by instant and repetitive news coverage that makes Nice or Paris seem as close as Orlando or Boston (and for my friends in France, recent attacks have been all too close). It is a small world thanks to global communication and the internet, and we know that terrorism, like other types of crime, can happen anywhere, so we shouldn’t be complacent. But we shouldn’t panic either.

Terrorism is a real problem, but it is not the end of the world, which is currently home to some 7.2 billion humans and countless other species. For perspective, note that in the US, something like 100 people die in car accidents each day. Worldwide, over a million people die annually in car accidents, and there are over half a million “intentional homicides” each year. So many lives tragically cut short every day, yet we hear nothing about most of these millions of deaths. Commercial plane crashes are rare, and when one does occur, many people may die, so it’s big news. The same with terrorist attacks, which have become more common worldwide, though nations like Iraq, Afghanistan, and Nigeria continue to bear the brunt of those attacks, even though attacks in Western countries get much more news coverage.  

You can Google for statistics as well as I can and find that you are more likely to be killed by falling furniture than by terrorism. My wife has recently told me she’s getting more concerned about my business travel, especially to Europe. But I am far safer on a business trip to anywhere in Europe, Japan, or Korea than I am driving my car to work. I’m not saying we shouldn’t be concerned about terrorism. It’s an awful thing if this is the “new normal,” and we shouldn’t simply accept that. We can and should come together worldwide to make progress against this threat, though it is certainly not the greatest threat to civilization that we face (that would be climate change).

Steven Pinker and others have pointed to extensive data to show that even as terrorism and crime fill the headlines, the world is not falling apart, and on an overall basis, violence in the world has greatly decreased, and not only because there are fewer wars.  Other forms of violence and cruelty are also greatly in decline, though they have not reached zero and probably never will. I’m optimistic that we can still build a better world for my grandchildren -- and for everyone else. We should not be complacent about terrorism, but we shouldn’t freak out, change our way of life, or start another war over it. 

The image above has nothing to do with it except that this is the planet we all happen to share (a screen shot from the free Orbiter space flight simulator, and one of my most popular pictures on Flickr). 

Wednesday, May 11, 2016

Sunspots


I love to write, though you might never guess this from my recent blog activity. While this is my first blog post of 2016, I used to blog a lot more -- some 1500 entries since I started this blog in 2005. Most of my writing these days is in a journal I keep on my iPhone and iPad using an app called Day One. I like keeping a journal, but recently I started to think about getting out of my comfort zone and doing something a little different with writing. Looking around, I found a wonderful organization called the Seven Bridges Writers' Collaborative in Lancaster, Massachusetts, just 20 minutes from me. There was an opening in one of their weekly creative writing groups, and I joined the spring session in late March. It's a small, informal group led by Winona Winkler Wendth, an experienced, insightful, and supportive writing teacher. I've enjoyed the writing exercises and the lively discussions each week with the group. And it has successfully gotten me out of my comfort zone, writing things I would never have thought to write, sometimes well, sometimes not so well.

Here is a new one that is very different for me. The prompt was simple -- write 300-500 words starting with "I counted. There were 27." It gave me some trouble for a day or so until I started thinking about the recent transit of Mercury, and about sunspots.

Sunspots

I counted. There were 27. Shining the sun on a paper plate with your telescope works great. I’ve never seen the sun like that. Is 27 a lot of sunspots?

Not really. Sometimes it can be over a hundred. It goes in cycles over something like eleven years. Twenty-seven is actually a pretty low number.

What do they mean?

What do you mean, what do they mean?

Sunspots. If you can’t see them without a special trick like this, why are they even there?

Well, they don’t mean anything. They’re just something that happens because of the way the sun works. Astronomers have figured out that sunspots are cooler areas on the sun, though they are still hotter than anything on Earth, and often they are as big as Earth. They only look small because the sun is so far away.

But how can they not mean anything? Isn’t there a reason for them?

There’s a difference between a reason and a meaning. Scientists can study the sun and figure out why events like sunspots and eclipses happen from information they can see and measure. In the past, people didn’t know as much about how the world works. They might see sunspots or eclipses as special signs, warnings about something bad. Some people still think this way, figuring that anything so strange and different from normal must mean something.

But isn’t that right? Grandma says everything happens for a reason.

Let’s think about what she means. Is she talking about science when she says that?

I don’t think so. She usually says it when someone gets sick or dies or something and people are sad.

Right. If everything were random and unpredictable, that could be pretty scary. But some things in the world happen pretty regularly, like day and night, right?

Sure.

And other things are not quite so regular, but we know something about them. We have weather forecasts, and we expect it to rain sometimes, and we know most summer days will be warmer than most winter days. If it rains and your baseball game is canceled, you might not be happy, but you don’t think it rained because someone didn’t want you to play your game, do you?

Of course not.

Rain happens for reasons you can study and learn about. But those reasons don’t have anything to do with what people want. And the rain doesn’t mean anything by itself, though you can find meaning in it. To some people rain means joy because it helps their flowers grow. Some may write poems and songs about the meanings they find in the world. Other people may be scientists and find joy and meaning in understanding the reasons for rain or sunspots or brain cells. People are the most complicated part of this complicated universe. Everyone studies people, but psychologists, writers, and some others do it in special ways.

Can we get ice cream now, Dad?

Yup.

Friday, December 18, 2015

My Theoretical Interests


I was going through my daily Google spam notification email, thinking about all the theoretical interests I have that now mostly show up as marketing emails. Democratic Party appeals, astronomy magazines, Optical Society information, TAXI songwriting promo offers, musical instrument sale offers, AOPA private pilot news, Japanese and French language study information, and much more. Most of these represent past or perhaps intermittently current interests, now mostly theoretical interests in that I do nothing with them 90% of the time.

Even the 146 apps on my iPad show this. So many astronomy, language study, music making, photography, and game apps that I hardly have time to even look at. But they don't take up any physical room, and you never know when some interest will strike again (hope springs eternal that 24 hours a day is only a temporary constraint). Books are like this too. An ever-growing backlog and I will probably never read 75% of them. I should at least clear out the many shelves of paper books that I am less likely than ever to read now that I'm totally hooked on the convenience of ebooks. But there I have the 10% problem -- I'm sure I will never need 90% of the paper books in my house. But I can't get rid of them until I identify the 10% I might need, and that is not a weekend project.

First world problems, I know, right? Such an abundance of riches. One that still grabs me is The Great Courses (this was the part of my daily spam that triggered this particular rant). College level lecture courses in every subject by some of the greatest professors in the world. I have a number of them as DVD and a couple as audio, and have watched or listened to a few lectures from some of them, but never completed one course. Yet I look every time for more, especially when there's a "big sale" (as there usually is). These days I rarely order any new courses because I know about my theoretical side. Like the way I'm a theoretical pilot and singer-songwriter ("flying singer," get it?).

[begin-rationalization] In fairness to myself, these theoretical interests really do still interest me, even if I don't have time to actively pursue everything. I like to "keep in touch" with private pilot, songwriting, and astronomy magazines and I follow some related organizations and people on Facebook (a source of serendipity as well as a few laughs every day). Every time I go to Japan, I brush up on my reading and conversation and learn a few new things (or buy a new app). On two trips to Korea this year, I taught myself enough Hangul phonetic script to decipher many signs. And I do read a lot of books on all sorts of subjects. Donald Trump has already scared me enough to start giving money to the Dems again (spam and fear are a winning combination, Democrat marketers). And every December (triggered by my company's year-end shutdown), I magically turn back into a singer-songwriter for a week or two, writing and recording some new songs with my producer and friend Roger Lavallee. Plus I have a job that still uses the optics I studied back in the 70s. So I guess I'm not a complete deadbeat. [/end-rationalization].
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Monday, November 09, 2015

No Explanation Needed


One definition of a tautology is the needless repetition of an idea, statement, or word. It strikes me that some of the "big questions" that are often discussed about the universe and life are little more than tautologies. They may be interesting to discuss, and if you believe in God or another cosmic consciousness or creator, they might even seem to have meaning. But based on what is actually observable, there is a big and complex physical universe that has been chugging along for billions of years, much longer than there have been human brains to do things like wonder why. And for a few thousand years, there have been human brains, some with enough security and free time to do the wondering. That's it!

The "anthropic principle" is the one that bugs me the most. This is the idea that since physical constants and conditions are suitable for stable matter, life, and intelligence, and since we can conceive of these things having been otherwise, someone or something must have set them that way so matter, life and intelligence can exist. But this is a tautology, since we wouldn't even be around if this were not true. If the conditions were wrong, or if there are multiple universes and some don't have these conditions, there would be no "we" around to wonder about this. It clearly assumes some purpose for the universe or a god or creator that could make decisions about this. And if that is the case, who or what created that creator, and in what universe, with what physical constants, defined by whom or what? It's an infinite regress.

Why not stick with what's observable? As far as I'm concerned, the universe simply is. That doesn't mean I can't be awed by its beauty or impressed with its intricacy, or that I can't be curious about its many parts and try to understand how some of them work (that's why I majored in physics). It just means I accept the universe as the natural state of things and that I don't believe it was created for the benefit of humans. We are simply one of the complex manifestations of its properties. Life with a cherry on top (more like cherry Jello).

There's a related question that is often asked about the universe: Why is there something rather than nothing? Again it's a tautology -- if there were nothing, nothing would exist to even think about this. There is no why there.

Sometimes people talk about "the will to live." I have often marveled myself at the enormous efforts that animals (including humans) will make to survive or even just carry on their normal life cycles. Things like certain migrating birds that fly thousands of miles twice a year to feed and reproduce. But the will to live is "baked into" life itself because natural selection eliminates those without it. So it's one of those things that is both amazing and commonplace, even inevitable. Of course it has some side-effects that we and some of our fellow creatures may perceive as happiness or contentment. When my dog and I are well-rested and well-fed and are enjoying the sights and smells of a walk on a sunny fall morning, that feeling came from evolution too. It's still pretty awesome.

And what about "are we alone in the universe?" This is a different kind of question, not a tautology. It's worth thinking about, and even doing some research, although it is not as exact question as some people may believe it to be. Clearly there is insufficient data now to evaluate this, though this may not always be so. Humans are certainly expending some effort to find information related to this question through space exploration and other means, and as we have identified thousands of exoplanets, we know at least that there are other places where life similar to ours could exist.

Many years ago, astronomer Frank Drake defined an equation that aims to estimate the number of intelligent civilizations in the universe. It identified some of the relevant parameters of this question, and defined them as probabilities, although some of them are not well enough defined to plausibly consider as a probability. Things like "the probability that an intelligent life form will develop a technological civilization." This is almost like asking "what is the probability that my karma is purple?" How to you define "karma?" Do karmas come in colors? How to you even define "intelligent life?" Does that mean "capable of developing technology?" Isn't that a tautology?

I just read an article describing a similar equation that considers the probability of detectable life. The "Seager Equation" is geared to our current knowledge of (many) exoplanets and how likely it is we could detect some planetary biosignatures. It is a bit more physical than Drake's equation, and does not consider intelligence or technology. A planet hosting only blue-green algae might have an oxygen-rich atmosphere detectable by spectroscopic methods if conditions like distance, star type, exoplanets in the habitable zone of the star, and others are right. The answer to this question? Her best estimate is 2. Not 42. Not millions. But not zero or .0005. That suggests it is worth looking.

I hope we are not alone in the universe. I hope there is simple life and intelligent life in abundance and that someday we can find it. But if we are alone, that's OK too. We will keep busy and maybe even survive to a ripe old age. We aren't here for any particular reason, but it's a great party, and I'm glad we crashed it.

-----

Nick Bostrom has a book on anthropic bias that apparently goes much more deeply into this subject. I haven't read it, but his web site has a lot of helpful information.

The picture here is by Slovak graphic designer Martin Vargic. It's a chart showing his artist's impressions of 500 of the some 2000 confirmed exoplanets arranged by mean temperature (x) vs. density (y). Although these planets have not been directly observed, the depictions are not completely  fictional, as they are based on temperature, density, metal content, and other factors (the rings are purely for looks -- they are pretty common in our solar system, but only prominent on Saturn).

Tuesday, October 27, 2015

Insane Convictions


For the first time this year, Donald Trump is starting to fall behind in polls of likely Republican primary voters, especially in Iowa but also in one major national poll (New York Times today). This would be good news were it not for the fact that it is Dr. Ben Carson who is catching up with The Donald. Trump's conviction is that he is simply the greatest. He's self-serving and egomaniacal and willing to say or do anything to get attention. He is also extremely rich and quite smart in his obnoxious way. Sometimes I think he is playing all of us, that this is all a big game of some sort, although he probably really does think he could be a good president.

Carson, on the other hand, may be certifiably insane. Here's a guy who had to have been brilliant at one time to achieve what he did as an innovative pediatric neurosurgeon. But he's also a Seventh-day Adventist who seems to be completely dominated by his religious beliefs. It's almost funny that he has talked about his fear of a Muslim president who might try to institute sharia law in the United States. This from a guy who clearly wants to impose his own Christian beliefs on our entire country, starting with no abortions for any reason, although in a recent interview, he seemed unable to connect this with the obvious GOP agenda step of reversing Roe vs. Wade. It seemed like he didn't really know what that was. He has strong, insane convictions, but very large gaps in his knowledge of how our country works. And of reality in general. He looks and sounds like he's on Thorazine or some other antipsychotic drug.

It's a testament to the power of religion to make you believe in strange things that he does not believe in evolution. Here's a man trained as a neurosurgeon who helped develop a surgical procedure to separate conjoined twins joined at the brain. I have to believe that some of the procedures that were developed for this and other surgical innovations were tested and practiced on animals such as dogs, monkeys, and maybe even chimps because of their anatomical similarities to humans. He must have noticed those resemblances and is perhaps even familiar with how bacteria become resistant to antibiotics (through evolution). And that all life on Earth uses the same DNA system that we do, and that the genomes of great apes are nearly identical to ours. I suppose Ben believes that God created all of the similarities just because he felt like it, even though humans were somehow independently created from all the other animals.

Ben also believes that homosexuality is a choice (and not unlike bestiality), that Obamacare is like Hitler, that abortion is like slavery, that people who are shot by mass killers simply failed to defend themselves, and on and on. This Salon article is a nice review of seven of his most insane statements:
  1. Gayness must be a choice, because prisoners who are raped come out gay.
  2. Obamacare is worse than slavery. We live in a Gestapo age.
  3. The Big Bang is a "fairy tale" and the notion of evolution was encouraged by the devil.
  4. There's no war on women; there may be a war on women's insides. [ WTF? -Ed. ]
  5. Nope, I don't see any global warming.
  6. Nope, I don't see any racism.
  7. Planned Parenthood is a plot to kill black babies.
Considering that Carson claims to have been a Democrat in 1992, it's tempting to believe that his current conservative views have been cherry-picked to appeal to right wing Republican voters, although he might truly believe in some or all of them. In this Yahoo Politics article, he even describes how he only learned in 2013 the right way for a Republican to talk about guns. It seems he actually believes that assault weapons should be restricted in urban areas, but of course a Republican can't say anything like this, you always have to start with "the Second Amendment is sacred, no restrictions on guns!"

So what is this dude's appeal? He's personally non-threatening, soft-spoken, ultra religious, and occasionally articulate-sounding. I can see how this sells among evangelicals in a place like Iowa if you don't look too closely at his ideas and beliefs. But I would hope that once the details of his views become better known, that mainstream Republican voters will quickly recognize what an insane and dangerous thing we have here in Ben Carson. We should not be considering handing the keys to the US nuclear arsenal to such an inexperienced and loopy guy, let alone a man who believes that the "End of Times" may soon be upon us.


Tuesday, September 15, 2015

Infinite Jest


Infinite Jest is a 1,079 page novel by the late David Foster Wallace (DFW). I haven't read it, but as I was updating some iPad apps and playing briefly with a synthesizer app called Magellan, the phrase popped into my head. The 1996 book is somewhat in the news because of a new movie "The End of the Tour," based on an interview with DFW by a Rolling Stone reporter played by Jesse Eisenberg. It sounds pretty dull but I guess it all depends. According to an article on how to fake having read Infinite Jest (because come on, who reads a 1000 page book?):
The Title: “Infinite jest” has three meanings in the context of the novel. It’s a Hamlet quote, the name of a fictional movie that’s impossible to stop watching, and a reference to our own culture of constant entertainment. [emphasis added]
I guess that's why "infinite jest" popped into my head. I was realizing that Magellan is possibly the most amazing musical instrument ever, and if I had had this one thing before the era of i-devices and the Internet, I might have spent weeks or months exploring and creating music with it. The sounds are beautiful and the flexibility is mind boggling.

But I've had this app for probably 2 years, and except for brief periods like this when I launch and play with it a while due to an app update, I hardly notice it. I have 143 apps on this iPad including at least 20 synthesizers (probably more since GarageBand has several synths built in). Every one of those synths is similarly worthy of hours or weeks of exploration and music creation. Yet I hardly notice them and have not written or recorded even a song fragment in months.

I can't blame my lack of creative output on "too many choices" but this does play a part. My journal does too. I'm not dying but sometimes it feels like I'm amusing myself to death with apps, Facebook, Flickr, Amazon Instant Video, Apple Music, and all the other trivial stuff vying for my attention.

In my personal hierarchy of worthy pursuits (outside of family and work), creating something is #1, especially if it's a completed song or recording (journal or blog writing gets partial credit). Learning something, usually by reading a book, is probably #2, and I still do spend a lot of my free time on that. But I wish I could figure out how to get past the fractal fragmentation of the culture of infinite jest. Usually a self-defined "special project" like making a new album does the trick, but I've defined several of these projects in the last year, and they too have succumbed to fragmentation. Maybe I need to lock myself in a room with nothing but a guitar. Would I have my iPhone too? It's a slippery slope.

Sunday, August 30, 2015

Gun Madness


I've been thinking about gun violence. It's always in the news because with over 33,000 gun deaths per year in the USA, we're never more than a few days away from a major national gun death story. Just the other day, a disgruntled, fired ex-reporter from a TV station in Virginia killed two of his former colleagues while they were on the air doing a live news interview. He later killed himself. I can't find the number, but there were probably at least two dozen other gun murders in America on August 26. Something like 25 to 30 murders occur daily along with many other gun deaths, suicides and accidents, an average of about 90 gun deaths per day nationwide.

Considering that we are supposed to be an "advanced country," this is obviously appalling, but there doesn't seem to be anything we can do about it because of our history and politics. The paranoid gun lobby opposes even the most minor commonsense restrictions on gun availability. I feel lucky to live in the state with the second lowest number of gun deaths and nearly the lowest rate of gun ownership in the country. Only Hawaii is better than Massachusetts. These statistics are obviously closely related, but that is not obvious to the many people who feel that even the slightest restriction on the right to buy, own, and use guns is a violation of their civil rights. But what about the civil rights of the thousands of people who are killed or injured by these guns?

There are some countries in South America and Africa where there are more per capita deaths due to gun violence then in the USA. But we are the only country in the world with an advanced economy and high levels of education that suffers such high rates of gun violence. The US has 88.8 guns per 100 people, the highest in the world. This must reflect many people owning multiple guns, because the range for household gun ownership goes from 60.6% in Alaska down to 9.7% in Hawaii. Of course gun death rates correlate closely with these statistics. Hawaii has 2.6 gun deaths per 100,000 people (Massachusetts has 3.1, 2013 figures). At the top end, Alaska has 19.8 deaths per 100,000 people (the rest of the top five is Louisiana, Alabama, Mississippi, Wyoming).

The national average for gun deaths in the US is 10.4 per 100,000 people. Compare this to some other advanced and seemingly still free countries: Australia 0.86, Canada 2.22, France 3.01, Germany 1.24, New Zealand 1.45, UK 0.26. Countries with numbers more similar to the US include Argentina 10.05, Uruguay 14.01, South Africa 21.5, Brazil 19.03, Mexico 11.2, Colombia 28.14, and Jamaica 39.7. Venezuela blows everybody away with 50.9 gun deaths per 100,000 people ("mixed years" says Wikipedia -- statistics vary in year and quality). I'm sure the US role as a leading market for illegal drugs helps push up the numbers in drug-source countries like Mexico and Columbia. Another benefit from the War on Drugs!

As I said to my wife last night, this feels something like an uncontrollable natural disaster or plague for us, like a monsoon or an earthquake that hits every few days. Or maybe like living next to an active volcano. Other countries somehow manage to get better at this as they become more educated and more prosperous. But not God-Blessed-America! Here it is tied to the willful ignorance of a big chunk of largely "God-fearing" people, many of whom also deny evolution and climate change and refuse to vaccinate their children. Aided and abetted by certain Republican, corporate, and religious leaders.

I will end this cheerful survey with an observation from Nicholas Kristof of the NY Times who pointed out recently that more Americans have died from domestic gun violence between 1968 and the present than have died in all wars fought by the US, including the Civil War (estimated at 750,000 deaths, though disease probably accounts for more of those than guns). This was fact checked by politifact.com and seems to be true, with about 1.4 million killed in American wars, versus 1.5 million in American streets and homes. There's the case for American exceptionalism right there.

Monday, August 03, 2015

Aurora: Generations Through the Void

Aurora is Kim Stanley Robinson's (KSR) new book, a science-fiction novel set about 400 years in the future. I really enjoyed it. The "Accelerando" (singularity) has occurred, and Earth has sent out a number of generation ships traveling at sub-lightspeed (0.1c) toward nearby stars with planetary systems. The story takes place on the Aurora, which is about 160 years into its journey and is nearing Tau Ceti. They are in their deceleration phase, using a continuous series of small hydrogen bomb explosions to slow them down so they can enter orbit around an Earth-like moon orbiting a "small Neptune" planet in the star's habitable zone. The ship has two large, rotating rings which each contain a set of twelve, 4 km long "biomes" that simulate specific environments on the earth, complete with weather, plants, animals, and human towns. There are around 2,100 6th-generation humans on board, and they apparently have their share of technical and social problems.

The story is largely narrated by Ship, a quantum computer-powered AI that operates all the systems on the Aurora. The lead engineer is a woman named Devi, and her adolescent daughter Freya is the main protagonist in the early part of the book. They are sixth and seventh generation descendents of the humans who boarded the ship 160 years earlier. At this time, Freya is going off on her coming-of-age "Wanderjahr" which provides a nice device for visiting and describing various parts of this huge ship. As usual in KSR space societies (and life), there are conflicts and rebels and troublemakers -- it is certainly no Utopia. But it makes for a lot of good storytelling.

Aurora is incrediby detailed, but thought provoking and engaging as KSR's books tend to be for me. It connects in some ways to his 2312 world, where there were human settlements on Mercury, Mars, the moons of Saturn, and in hollowed-out asteroids, but in many ways it's an anti-space, pro-environment book, which is consistent with some of the things I read in a recent interview with KSR. Human beings are animals which have co-evolved with all the other life forms within Earth's environment. It's quite a trick to build a spaceship or a space settlement where humans can live for a while, and an even cooler trick to build one that can function as a closed environment for 170+ years. But in the end, this environment and the environment of some "earthlike" planet are just poor imitations of where humans are meant to be, the Earth.

I say "meant to be" not in some philosophical destiny sense, but purely in an evolutionary and environmental sense, as KSR depicts in this book. Aurora is huge for a spaceship, and equipped with multiple "biomes" modeled on various Earth environments. Everything the designers could think of is there to form a closed life-support system, but they couldn't think of everything -- for example, they did not fully account for variable rates of evolution between large mammals and bacteria. They experience some of problems of island evolution with small populations. The cleverness and persistence of people like Devi and of the ship's AI allow them to overcome many of the problems for many years, all the way to Tau Ceti, where they encounter other problems.

MINOR SPOILER: Not all of the inhabitants of Aurora decide to settle in the Tau Ceti system. The trip back to Earth for a subset of the settlers (the "backers") turns into a struggle and a nightmare for these descendants of the original crew. Those people wanted to go, to be the pioneers, or at least the ancestors of the true pioneers. But they didn't fully realize what they would be inflicting on their children and great-great-grandchildren on the long voyage. Perhaps that is true whenever humans migrate from one place to a new place, but at least all such moves to date have taken place here on Earth where the environment is largely compatible with our bodies.

Although I'm more optimistic than KSR that we can eventually solve many of these problems, I still think that evolution and other things could make such small-population multi-generation ships very inhospitable, at least for some of the people. Unless there turn out to be things like wormholes or other shortcuts through deep space time, I think it's unlikely that humans will ever be taking interstellar voyages, at least not in our original biological bodies. If there are to be centuries-long voyages, I suspect they will be made by post-human beings in non-biological or perhaps hybrid bodies.