All posts for the month February, 2005

A while back I wrote about this huge video project we’ve undertaken at the company my husband and I run. Basically it all stems from the planetarium world changing from a realm of starballs and slide projectors to a realm where digital video also paints the dome. The change represents a huge leap from making slides and figuring out how to move them around the dome (using mirrors to reflect images, etc.) to learning video production tools and being worried about resolution and rendering times. All this before you put a single image on the dome or a single word down on tape for the soundtrack. (Tape? What’s tape? These days it’s all digital audio!).

Zeiss projector, courtesy the Exhibit Museum of the University of Michigan, Ann Arbor

Zeiss projector (Carl Zeiss)

Most of us grew up going to see a planetarium instrument that looked something like the ones below.

Lots of memories around those lovely projectors! I first learned to work one at Fiske Planetarium in Boulder, Colorado. There is NOTHING like taking the controls of a star instrument and literally making the universe do what you want it to!

Now, mind you, those instruments aren’t going away, even in this new realm of fulldome video. Some theaters are replacing their opto-mechanical systems with video, but some are opting to have BOTH types of projection systems under one dome.

So, next time you walk into your local planetarium, you might see one of those instruments above, but there might also be something that looks like a box with a huge lens on top of it, all controlled by a computer (maybe even a laptop).

How does this affect us? Well, now we get to be video production types, taking the shows we used to do with slides and mirrors, and applying all the latest techniques to fulldome video production. It’s a huge paradigm shift, to be sure. But it’s also challenging and fun and stimulating.

I’ve been running Seti@Home on my computer for a few years now and have managed to crank out a few thousand work units for the cause. Its seems like an easy-enough contribution to science: donate unused computer cycles to some giant distributed-computing project. I like the screensaver—it’s spiffy-looking and gives me some idea of the progress my machine is making as it crunches data from stellar signals.

So, why not try it? If you’re interested, you can sign up and get started over at

If searching for signals from ET isn’t your cup of tea, maybe you’d like to help out with some astrophysical researchers trying to detect gravitational waves. These are ripples in the fabric of space and time, emanating from such violent events in the cosmos as black hole collisions and supernovae, the action around rapidly rotating compact stars, and between active members of binary systems. These ripples travel through space, carrying information both about their source and about the nature of gravity itself. And there are two groups of astrophysicists trying to detect them: the LIGO and the GEO-600 collaboration. Their measurements are producing data that needs crunching, and why not use the world’s desktops as a powerful tool, just as the Seti@Home folks do with their distributed computing? If you’re interested in that project, you can visit the Einstein@Home project.

These are two of many other distributing computer projects that make solid contributions to science every day. I think it’s pretty cool that people and their home computers can be a part of Big Science!

Still from aurora movie

Still from aurora movie

Ever since the Pioneer and Voyager missions to the outer planets in the late 70s and early 80s, planetary scientists have known about Saturn’s aurorae. Hubble Space Telescope scientists have tracked the eerie glows over the past decade and a half using ultraviolet filters and instruments to study the characteristics of these emissions-related events. Recent studies using the Hubble Space Telescope and Cassini spacecraft show that the dancing light of the auroras on Saturn behaves in ways different from how scientists have thought possible for the last 25 years.

To get the image above, astronomers combined HST and Cassini ultraviolet images of Saturn’s southern polar region with visible-light images of the planet and its rings to make this picture. The auroral display appears blue because of the glow of ultraviolet light. In reality, the aurora would appear red to an observer at Saturn because of the presence of glowing hydrogen in the atmosphere. On Earth, charged particles from the Sun collide with nitrogen and oxygen in the upper atmosphere, creating auroral displays colored mostly green and blue.

If you click on the link above, you’ll see a “movie” of the Saturnian aurorae,dancing around the auroral “oval” at one of the planets’ poles. For more pictures and videos, visit the European Space Agency’s Hubble releases page.