Musings on optics, physics, astronomy, technology and life

Archive for July, 2012

My latest news articles for OPN

I write news briefs for the Optics & Photonics News website roughly every other week, with some slight schedule variations due to holidays and such. Here’s your invitation to read the last three articles while they’re still online.

Read this article first, because it’s been up there the longest: The folks at JILA (the place that used to be called the Joint Institute for Laboratory Astrophysics) have developed a tabletop-sized device that is a source of coherent X-rays. Coherence, of course, means that the light waves are “marching in step.” The beams that come from the medical X-ray device in your doctor’s or dentist’s office are no more coherent than the light from an incandescent bulb. (I hadn’t realized that before I did this article, but there you have it.)

Also, before this JILA invention, if you wanted an X-ray laser beam, you had to go to a particle accelerator facility. There aren’t too many sufficiently powerful particle accelerators out there, and you can’t exactly fit them into a doctor’s office.

Now, coherent X-ray beams aren’t going to be used in emergency rooms anytime soon. However, they could be extremely useful in studying the ultrafast details of chemical and biological processes, so it might be handy to have one in those kinds of laboratories. You can read more about this device and the scientists who built it in Nature, on and on JILA’s own website.

In the second newsbrief, I wrote about a new type of solar cell made from carbon nanotubes, developed at MIT. These tubes are just tiny bits of rolled-up graphene, which in turn is a two-dimensional lattice of carbon atoms. Both graphene and carbon nanotubes are extremely hot research topics right now, and I have been interested in solar technology for many years, so I enjoyed writing this one. You can see the actual solar-cell material in the photo accompanying this MIT press release, though I think the image looks like not-very-impressive orange mush.

My most recent article took me back to the “world’s fastest camera” that I wrote about three years ago, while I was still a staff writer at OPN. The UCLA team that invented that camera answered the question “What is it good for?” by demonstrating that it can scan blood samples for rogue cancer cells that break off a primary tumor and move through the bloodstream to metastasize elsewhere in the body. Of course, many, many clinical trials will be needed before it can be used on actual cancer patients, but any potential new tool in the battle against cancer makes me hopeful for the future.


A graphic demonstration

A couple of entries ago, I alluded to the powerful storm that knocked out electrical power to more than 1 million customers in the mid-Atlantic region. A NASA imaging satellite has captured before-and-after pictures of the region at night — and the results reveal something about light pollution, too.

NASA’s Suomi National Polar-orbiting Partnership spacecraft, a project based right here in my current community of Greenbelt, Maryland, imaged the region just before and after the storm last Friday night. Be sure to click on the “View Image Comparison” button — it takes you to a layered image with a “slider” so you can “blink” between the two photographs.

Granted, after the storm the Philadelphia, Delaware and Eastern Shore (Maryland) regions were covered with clouds. But you can definitely see the widespread outages all over the area west of the Chesapeake Bay. Not everyone lost power — you can see where the cities are, but they looked “dimmer” from outer space.

Of course, we use electrical power for lots of things besides lighting. However, we Americans tend not to be models of prudence when it comes to outdoor lighting, and we end up sending an awful lot of lumens up into the sky, especially when we live close to each other. I wonder how many people looked up at the night sky after the storm (maybe very late Friday night/early Saturday morning, or Saturday evening) and noticed a difference. Was there indeed a difference? I’m curious whether anyone made reasonably quantitative measurements. (Sorry, I didn’t.)

Courtesy of my Google Alert, here are a few more news article on The City Dark from, the International Business Times, the Pittsburgh Post-Gazette and the Chicago Sun-Times. Also, Discovery News offers tips on how to view the Milky Way — that is, if you can get far away from the murk of the cities to detect it at all.

A “point of view” you absolutely must see

As if someone at PBS headquarters was reading Optics & Photonics News (I wish!), PBS has scheduled the wonderful documentary The City Dark for its “POV” summer documentary series.

I saw The City Dark earliest this year at an environmental film in Washington, D.C. Why, yes, I just happened to be working on my OPN article at the time, but I would have appreciated the movie even if I had no plans to write about light pollution. It’s just more lyrical and expressive than I can manage. (I used to think I was pretty eloquent, but that was back in the day when electric typewriters still set the standard for individual written communication.) And it had Neil deGrasse Tyson. I’ve seen Neil deGrasse Tyson in person a couple of times, most recently (well, a couple of  years ago) at a retirement “roast” for longtime American Astronomical Society press officer Steve Maran. When it comes to communicating astronomy to the public, Neil deGrasse Tyson rocks my world.

Anyhow, you can watch the trailer for The City Dark on the PBS website and check the local listings for the film, because PBS stations often do their own thing. Supposedly, “POV” is a Thursday night feature, but here in the Washington area, WETA is airing the documentary on Saturday, July 7, at 11:15 p.m. Also check out for information where you can see it possibly on a larger screen than you have at home and/or with a bunch of like-minded people besides your own family.

Welcome again!

If you’re coming to this blog from my feature article on light pollution in the July/August issue of OPN, welcome!

I mentioned my blog at the end of the article for the simple reason that I found out way, way more information about light pollution than I could ever cram into a magazine article of a manageable length. And news is always coming out about the subject, even as I sit here and type this. So I thought I’d experiment by blogging updates to my article, at least for a month (or two, since OPN combines its July and August issues into one).

First off, if you are on Facebook and don’t already “Like” my science-writing page, please do so! On some days, it’s just easier to forward an interesting link that someone else posted than to do the writeup myself. Of course, on my Facebook page as well as on this blog, not all the posts are concerned with light pollution. However, I try to keep them reasonably focused on science topics that I find interesting or novel.

Second, the world’s premier organization fighting light pollution, the International Dark-Sky Association, also has a Facebook page. I follow it closely.

Although I wish I could write more tonight, I hate to spend too much time on a single entry right now. Thanks to this weekend’s derecho, electrical power in my region is tenuous. I had one outage from Friday night through yesterday evening, and a second blackout for about two and a half hours tonight. I’m not entirely convinced I won’t get a third before things get back to normal.