All Your Light Are Belong to Us

Here’s an interesting thing to ponder as you’re out watching the reflected light from the planets gleam at you over the next few nights:  almost all the photos of light (and this includes everything from ultraviolet to far infrared) ever emitted by all the galaxies that ever existed in the history of the universe is still traveling through the universe.

Light contains information about the universe in all its phases throughout history. If we could carefully measure the number and energy (the wavelength) of all the photons of light throughout history, we’d know some pretty cosmic things. In a very cosmic sense. We might find out how galaxies of long ago differed from those of today, for example.  This “extragalactic background light” is tremendously difficult to measure, though. We’re inside a very bright galaxy, and that drowns out this bath of ancient and young photons.  So, astronomers are looking for other ways to measure this bath of light from across time and space.  They found one, by measuring this background light by looking at the absorption of very high-energy gamma rays from distant blazars. Those are supermassive black holes in the centers of galaxies that are pointing their jets right at us across space.  Not all the gamma rays reach us — so scientists figured out how much gamma radiation is missing by studying the gamma rays that DO reach us.

This technique yielded a HUGE result. Astronomers have been able for the first time to measure the evolution (changes in) the extragalactic background light over the past five billion years — essentially since about the time the Sun and planets began to form. And, they found out that the kinds of galaxies we observe today are responsible for all the EBL over all time. There are more distant, earlier galaxies emitting gamma rays, but they are beyond what’s called the Cosmic Gamma Ray Horizon, and that poses more challenges to astronomers wanting to measure light from even earlier times.

Still, it’s an interesting way to study the universe. And, on a late spring night, when you’re out looking at the planets in the west after sunset, it’s interesting to ponder what else there lies out there to be discovered.

Want to know more about this study?  Check out the University of California’s High-Performance Astrocomputer Center’s announcement about this discovery.

My Life with the Firehose of Cosmic Information

I have a new book coming out!  It’s called Astronomy 101: From the Sun and Moon to Wormholes and Warp Drive, Key Theories, Discoveries, and Facts about the Universe, due out in a few weeks from Adams Media. I’ve been working with them behind the scenes on distribution and publicity, and so fairly soon they’ll turn on the switch and Astronomy 101 will step out into the spotlight. Stay tuned and I’ll let you know when it’s available. Or, you can go to the Astronomy 101 page on Amazon and put in a pre-order. Currently it says July 18th, but I think it may come out sooner.

I’ve been writing about astronomy for a long time. It began when I was in college as an undergraduate, and just grew from there. Of course, I’ve always been interested in the stars and space travel. That’s a natural outgrowth of growing up when we were still sending people to space and expecting to go to Mars any time in the near future. I’ve written before about how my parents got me interested in the stars. My dad, in particular, would take me outside at night and show me the sky, and occasionally would wake us up to see comets and meteor showers. So, I guess you could say that astronomy is in my DNA. Which is true of all of us, in a very real sense. We ARE star stuff because all the atoms in our bodies came either from the Big Bang (in the case of hydrogen) or from stars (in the case of the iron in our blood, the calcium in our bones, the oxygen we breathe, and so on).

Over the years, I’ve written or co-written a number of books, articles, and scripts about astronomy. My first book was called “Jupiter!” and it featured the space art of Don Davis (an old and dear friend). My next books were about Hubble Space Telescope, and called Hubble Vision, and written with John Brandt. We had a blast bringing the science of HST to the world. We also did a general astronomy book together, too, called Visions of the Cosmos.  A few years later, I teamed up with other editors from Sky & Telescope to work on The New Solar System and Deep-Sky Wonders as an editor.

Outnumbering my books are my videos. You can see every planetarium fulldome show I’ve ever written by simply visiting Loch Ness Productions’ Web site and clicking on the shows link. I’m still writing these shows, and enjoy creating for both fulldome and flatscreen theaters. The most recent one I did was for the International Dark-Sky Association, called Losing the Dark.  It has been translated to seven languages, with ten more on the way.  In recent years, I’ve also taken on doing a Web-based stargazing show called Our Night Sky and an occasional astronomy special called The Astronomer’s Universe for Astrocast.TV, an Web-based video news site focused on astronomy and space science.

So, back to my new book.  As you can see, I’ve been writing for just about any medium I can lay hands on. But, it’s been a while since I’ve done a book. In fact, for awhile after my last book, I thought I probably wouldn’t do another one, given the advent of electronic media and the fact that I’ve been busy writing and producing videos and podcasts.

But, a few months ago, a print publisher got in touch with me and asked if I’d like to do a popular-level book on astronomy which would be available in BOTH print AND eBook formats.  I gave it some thought and decided to give it a whack. Creating for both print and eBooks imposes some distinct requirements on a writer and publisher that we didn’t face back when books were only tree-based. For example, illustrations have to be very clean and easy to reproduce in eBook format.  We still have color images in the book, which is great.

Now, the idea of a very general book on astronomy is nothing new. The publishers wanted to do something a little different: they wanted to have a book you could pick up, flip through, choose a topic, and read a thousand or so words on that topic and get a good bite-sized idea of it.  No math, no equations, just some storytelling and a few interesting facts to pique your interest. And, that’s the book they asked me to do.

This is where the firehose idea comes in. Astronomy is HUGE. There are thousands of topics that you could write about. Literally.  But, I had to pick about 55 or 60, and write about those. So, I did. On a tremendously tight deadline (welcome to the NEW world of publishing, folks!). The result is, I hope, a handy little book that you could read. Or, if you’re already knowledgeable about astronomy, a book you might give to someone else who is smart and wants to know more about a topic they’ve always been interested in but hadn’t had much time to study. I wrote this book with busy folks in mind—teachers, police officers, politicians (maybe?), cab drivers, lawyers, doctors, librarians, musicians—pretty much anybody who wants to know more about astronomy, but didn’t really study it in school.

Now, while my name shows up on the front of the book, I couldn’t have done it without my group of background readers, mostly astronomers, who read drafts and gave me tremendously good feedback. I had only a couple of months to write the book, and so their honest opinions, error-checking, and moral support were incredibly helpful. Their names are listed in the front of the book as my “posse”, and I couldn’t have done it without them!

Check out the link at Amazon, give Astronomy 101 a pre-order and tell your friends that there’s a new astronomy book coming out they might want to check out! And, once you get it and have given it a read, let me know what you think. While one or two of my other books are about to go (or have gone) to eBook editions from their older print editions, this one is the first book I’ve done specifically for this hot new environment of electronic publishing, so I am anxious to see how it turns out.