Leap Years and How Scientists Tell Time

I couldn't let Feb. 29th go by without commenting on leap years, especially since I have no expectation that this blog will still be around four years from now. Leap years originate in astronomy -- the length of the year (the time it takes the Earth to go around the sun), is not an even number of days (the time it takes the earth to rotate on its axis). The length of the year is roughly 365.2422 days. Lucky for us, the fractional part of the year (0.2422) is almost equal to 0.25 (or 1/4), so we can fix things by adding 1/4 of a day every year, or one day every four years. This "fix" was introduced by the ancient Romans, and it works pretty well, but it's still not perfect. The Gregorian calendar fixes the fix by taking away leap days every 100 years (so, for instance 1800 and 1900 were not leap years) and then adding them back in every 400 years, so 2000 was a leap year. Our leap year in 2000 is something we won't see again until 2400! This gives us a length of the year equal to 365 + 1/4 - 1/100 + 1/400 = 365.2425 days, which means the calendar will be off by one day every 3333 years -- not too shabby!

Calendar reform had a symbiotic relationship with the infant science of astronomy. It's really just a weird coincidence that a simple leap year works so well, but not well enough that it didn't need to be fixed later on. Would science have developed any differently if the year were more exactly a simple fraction of the number of days, so that the Gregorian reform had not been necessary? And what if the opposite had been true? What if the year weren't anywhere close to a simple fraction of the number of days? Would that have led to much greater calendrical confusion over the centuries?

Given all of this confusion, what unit of time do scientists use in their own work?  Days? Years? Hours? Minutes? The answer is none of the above.

The Flat Universe Society

In my peregrinations around the Internet, I have discovered not one, but two websites devoted to the Flat Earth Society:

www.theflatearthsociety.org
and
www.tfes.org

I think one is a splinter group from the other. I bet they hate each other.

But why limit ourselves to a binary choice? Why does the alternative to a round Earth have to be a flat Earth? Let's be creative and think of other possibilities.

Maybe the Earth is actually shaped like a torus (a gigantic donut):

This is even better than a sphere -- now there are two different ways to go around the world! You can sail around the outside of the donut, or you can circle the world through the donut hole.

Or maybe the surface of the Earth has negative curvature, like a saddle or a Pringles potato chip:

Of course, this isn't what the Earth looks like. But it's what the entire universe might look like.

Gravitational Radiation and the Search for Extraterrestrial Intelligence

With the first direct detection of gravitational radiation by LIGO, we've entered a new era in science. Gravitational wave astronomy promises to be the most exciting field in the physical sciences for the next decade. So should we start looking for signals from ET in this data?

First Detection of Gravitational Radiation?

It's totally irresponsible for scientists to spread rumors on the Internet, so I will wait until after the break to do so.

Dell Award for Undergraduate Science Fiction Writing

This past fall marked the third time that Professor Jay Clayton and I taught our Vanderbilt seminar on science and science fiction. As a final exercise, the students usually choose to write their own short stories. (They also have the option of writing a "popular science" article or a critical essay, but only one student has chosen this in the entire history of the class!) We've always entered the best of the students' stories in the competition for the Dell Award for undergraduate science fiction writing. This year, our students took first place and third place in the competition!

Thought for the Day: Snow Edition

Nashville received a backhand blow from the storm that knocked out the East Coast: we got 8 inches of snow (the heaviest snowfall since I've lived here), which completely paralyzed the city. Nashville's method of snow removal is called "solar power." We lost electricity for several hours on Saturday morning and watched helplessly as the temperature inside the house dropped about a degree every hour. Power was restored before it got too uncomfortable, but this led me to the following thought experiment. Suppose that all of our technological infrastructure (electricity, gas, cable TV) collapsed for a month in the middle of the winter. Which one of these people would you want at your side to help you survive?

The Kardashev Scale for Extraterrestrial Civilizations

Back in the 1960s, the Soviet scientist Nikolai Kardashev proposed a scale to measure the technological level of extraterrestrial civilizations. I was reminded of his work by this paper, which appeared today. Here is an explanation of the Kardashev scale, with some minor additions of my own:

The Historical Memory of Children

I'm too young to remember the day that John F. Kennedy was assassinated, but I remember the assassination of Martin Luther King with crystal clarity. I was 9 years old at the time, attending a small Catholic school in St. Louis. The morning after King was assassinated, all of the nuns at my school were deeply upset, which puzzled me, because I was under the impression that Martin Luther had been assassinated. A little historical knowledge is a dangerous thing, and we forget what it was like to be young and have such a distorted understanding of history.

Happy 50th Anniversary, Batman!

Yesterday was the 50th anniversary of the premier of Batman, the television show. It's difficult today, within our fractured popular culture, to appreciate what an overwhelming phenomenon this show was at the time, but I can give one example from personal experience.

When Young People Watch Old Movies

In preparation for taking my children to the latest Star Wars movie, we pulled our copies of the original Star Wars trilogy out of storage for the kids to watch. And what did my kids think of them? One main comment: the special effects weren't very good.

Now when I was a kid, special effects were downright awful, and yet I somehow managed to look past them to enjoy all of the classic SF movies of the 50s and 60s. I know this sounds like the typical complaints of a grumpy middle-aged man about how when I was a kid ... a line of argument that goes back, I believe, to the ancient Sumerians.

How to Raise a Scientist in the Xbox Age

I had another op-ed in the Wall Street Journal a few weeks ago, entitled "How to Raise a Scientist in the Xbox Age."  You can't read it unless you are a subscriber -- the Wall Street Journal is behind a paywall that makes the Berlin Wall look like a speed bump -- but the article basically details my experiences growing up as proto-scientist in the 1960s and 70s.

Puzzling Expressions from Science

Many expressions from science have entered our everyday vocabulary, but sometimes in ways that are puzzling. Here are a few that I have wondered about -- perhaps some of you can explain them:

1.  Guinea pig. This is now a colloquial expression for any experimental subject. But biomedical research is performed mostly with rats and mice. So instead of saying, "Can you be my guinea pig for this recipe?" why don't we say, "Can you be my rat for this recipe?" Were guinea pigs much more important in research fifty or a hundred years ago? If so, it certainly wasn't for ease of breeding. We used to own a guinea pig, and they do not "breed like rabbits" -- more like pandas. I should note that the term "lab rat" seems to be entering the popular vocabulary, so maybe it will eventually displace "guinea pig."

Star Wars (INCLUDES SPOILERS)

So I finally got to see Star Wars VII. (Why is it that only Star Wars movies and Super Bowls rate Roman numerals?) Of course, Star Wars isn't really science fiction -- it's a fantasy set it space -- but I really enjoyed the first three Star Wars movies (or as my children would say, the second three movies).  I would rank the newest Star Wars offering well below the first three (i.e., the second three), but much better than the second three movies (i.e., the first three). At first I enjoyed the constant references to the first (fourth) movie, but after a while it became apparent that the entire film was just that -- a remix of the original Star Wars, which made it all too predictable. And why did the bad guy come across as an unpleasant Star Wars fan-boy who looked and sounded like he had just stepped out of a Jane Austen film?

MAJOR SPOILER AFTER THE BREAK

New Names Announced for Exoplanets and Stars

The International Astronomical Union (IAU) has just announced the official new names for a large number of exoplanets (i.e., planets orbiting other stars). You can read the full list here. (Thanks to my colleague Susan Stewart of the US Naval Observatory for pointing this out). The IAU is the organization that has the authority to confer official names on extraterrestrial objects. That place you paid to name a star after your girlfriend does not have this authority. The IAU had some sort of competition involving nominations from the public, which you can read about on their website.

This list will be of particular interest to science fiction writers out there -- it gives a whole bunch of new names for nearby planets. (For fictional planet names, you really can't beat Larry Niven's Known Space series.  His planets include We Made It, Jinx, Plateau, Home, and Down). But I do have one problem with the IAU list -- they also renamed a bunch of stars! For some stars, it's a clear improvement.  HD 149026 has been named "Ogma" (much easier to remember), while PSR 1257+12 (not an easy name to remember) is now called "Lich." But they renamed some fairly well-known stars as well. The prime example is epsilon Eridani, which is now supposed to be called "Ran." But epsilon Eridani is a famous star, visible to the naked eye. Maybe I'm just annoyed because I used it in a story that I sent off a few weeks ago. But I'm sure it's been used in countless other SF stories as well. And frankly, Ran just doesn't sound as good.

Class Blog for Science/Science Fiction Seminar

Yesterday was the last day of classes at Vanderbilt, and so the last day of our seminar on science and science fiction. We had a great group of students this year, and the class was a joy to teach. As part of their class assignments, the students were required to write blog posts periodically. The result was an eclectic mix of reflections on the readings for the course, discussion of general issues in science fiction, and original science fiction from the students. I encourage you to take a look at it; the URL is vusf.wordpress.com.