Archive for December, 2014

Cosmic Calendar: The Big Bang



Thirteen billion seven hundred ninety-eight million years ago (give or take thirty-seven million years), an unimaginably small, massive, timeless point erupted. Time and space sprang into being.

What came before that is a question that may or may not make sense (as time itself is said to have been tied up in that initial singularity). At any rate, for now it is a question for philosophers as much as for scientists. Whether there was a “before”, either temporally or causally, we pick the first moment of the singularity’s expansion as our starting point for this calendar.

The earliest moments of January first on the Cosmic Calendar are taken up with a fury of growth and change. There was a period of exponential expansion. Speculation is that some (still mysterious) process generated a slight excess of matter over antimatter (one part in 30 million), leading to a present universe with matter dominant over antimatter.

About ten nanoseconds in, the universe cooled to the energies we can produce in particle physics experiments today. Around a microsecond, we started getting protons and neutrons out of the particle/energy soup. In the first few minutes, we started getting deuterium and helium nuclei forming.

That’s actual nanoseconds and microseconds and minutes. On the one-year scale of the Cosmic Calendar, all of this is happening unimaginably quicker. Why not watch a (safe and responsible) fireworks display. If a firework happens to go off right at the stroke of midnight, then the chemical reactions driving that explosion could be thought of as an extremely slow-motion recreation of an event that is materially, energetically, and temporally completely unlike the big bang. (But it makes a nice symbol, no?)

Following the initial explosion, it was all about energy. Most of what there was in the universe was just energy. After several thousand years, matter (protons, neutrons, electrons, etc) began to dominate the picture. Exactly when did this happen? I am unable to pin down a clear answer. This scantily-referenced paragraph on Wikipedia says 70 thousand years, which would point to a calendar time two minutes and forty seconds after midnight. This university teaching page says 50 thousand, which is one minute 54 seconds into the year. At any rate, if your energy levels to drop in the first three minutes of the year, I suggest consuming some form of matter – nachos perhaps, or vegetables. Aside from hydrogen, the most common element (bare nuclei, not stable atoms at this point) was helium. But I am very definitely not recommending that you use helium balloons to alter your voice. It might be appropriately reverent, but we are past peak helium, so it would also be irresponsible.

Between 377 000 and 487 000 years after the bang (that’s 00:14:22 to 00:18:33 on New Year’s Day), recombination and decoupling occurred. Recombination is when the first complex atomic nuclei, such as deuterium and helium, formed. Decoupling meant that photons started being able to fly free, rather than always slamming into bits of matter. This meant something new – something that we can observe today. You see, some of those photons are still zipping along. We can detect them now as the Cosmic Microwave Background Radiation. If you like, you could celebrate this by spending those four minutes watching snow on an old analogue television set. Or you could listen to John Cramer’s audio reproduction (available in 20-second, 50-second, 100-second, 200-second, and 500-second versions).

Now we’re well into the New Year – on our way to the universe as we know it. I don’t have any more milestones for this first day, so perhaps we should all get some sleep.

What is your favorite part of this opening fiesta of generation and diversification? Can you spot any interesting events or transitions that I’ve left out of this description?

Scientific References:

National Research Council of Canada article on age of universe
NASA WMAP report
ESA Planck report

Further reading:

Wikipedia: Timeline of the Big Bang
Wikipedia: Recombination
Wikipedia: Decoupling
Wikipedia: Cosmic Microwave Background Radiation
Audio version of the CMBR

Fireworks image: “Fireworks white red“, by Tuan Hung Nguyen, Public Domain


Back into the Cosmic Calendar


In the past, I have talked about the Cosmic Calendar. It is a grand idea, first introduced (to my knowledge) by Carl Sagan in his Cosmos series. Since then, though, I’ve sort of let it fall off the radar. I still think about the Cosmic Calendar, particularly in the last half of December with the Evolutionary Advent – interesting events virtually every day, and several on the last day of the year.

Anyway, I am currently working to build a more complete tour through the year. This renewed interest is inspired partly by my own children’s blossoming curiosity about everything, and partly by the new Cosmos series, hosted by Neil De Grasse Tyson (available, among other places, on Netflix in Canada). He recapitulates the Cosmic Calendar in the first episode.

Next year, I plan to post along with the cosmic calendar, going into a little more detail on each event: what happened, how it fits into the great epic of cosmic history, and some thoughts on how science-minded folks might celebrate it.

The basic idea is not my own: as far as I know, that credit goes to Carl Sagan and his collaborators on the original Cosmos series. What I will present is my own riff on it, expanding the basic idea to a full, year-long cycle of celebration and education. I will include figures that are as accurate as my layman’s research can get. I will offer suggestions about how humanists and other science fans might celebrate each cosmic event throughout the year

I will try to keep the technical language light, but not at the expense of glossing over important or fun details.

If you want to plan your own celebrations for any of the events, do check out my Cosmic Calendar page, where I list all of the events I have been able to identify and verify (already over fifty), with links to my own posts on them individually. I have also linked to other sites and individuals who, like me, want to evangelize this awesome idea to anyone interested.

I still maintain the Google Calendar with all of these events, which is open for anyone to link to or copy.

While I would love to just jump in now, as the events start to come more quickly, I have decided instead to start fresh on January 1st – the Big Bang. I am already composing and lining up the posts. I will carry on through the full year. I currently have 50+ events lined up, and I’m looking for more. Depending on the interest and feedback I receive, I may continue this in subsequent years. (In particular, things shift a little in a leap year, because the cosmos-to-days scale is adjusted by one day.)

If you have any Cosmic events that you would like me to cover, please feel free to leave a comment on this post and I will look into it. If, during the course of the year, you notice any scientific blunders on my part, let me know and I will verify and fix them.