Bill Blair's

Education and Outreach Page

"How Much is a Billion?"

Perspective is important, not only in astronomy, but anywhere very large numbers are involved.

Here is a little presentation I put together in an attempt to make the concept of a "billion" people understandable (at some level!). It ends with a twist to put the expected increase in world population into context. Hope you like it! Available in Powerpoint (<1 Mb) or PDF (<18 Mb) formats.

Size and Scale of the Universe

The immensity of the Universe is at best difficult to fathom. Huge distances and sizes, expressed in millions of miles or light years, just become "big" numbers to our ears; they really have no meaning. In giving numerous presentations to various school groups or in making public presentations, I have developed some simple demonstrations that have been effective in communicating a sense of the size and scale of the solar system, the galaxy, and the Universe. If this sounds interesting to you, the following two write-ups may be of some interest:

Middle School Exercise: Calculating the Distance to the Cygnus Loop supernova remnant

This is a web-based, self-contained exercise for middle school level that can be printed out and used or just appreciated on-line. Uses real Hubble and ground-based data with simple arithmetic and an eensy-weensy bit of trigonometry to calculate the distance to the Cygnus Loop supernova remnant, just like a real astronomer would do it!

Learning from Light

It is truly amazing that we can learn so much about objects in the distant Universe just by analyzing the light that they send us across the endless void of space. Everyone is familiar with the astonishing and beautiful astronomical images obtained by large ground-based and space-based telescopes such as those at Mount Palomar, Kitt Peak, and of course, the Hubble Space Telescope and more recently the James Webb Space Telescope (which observes infrared light). But much of our information about the Universe comes out of a technique called astronomical spectroscopy, where the light from an object is dispersed into into a spectrum for analysis. The Hubble, for instance, carries both cameras and spectrographs, and yet what does the public ever hear about the results from the spectrographs, which is where the real quantitative information is primarily obtained? Nothing!

As my own attempt to deal with this issue, I have developed a Web site that attempts to describe the "Basics of Light" and "Astronomical Spectroscopy" at a level understandable at the junior high to high school level. I have no pretenses that you will ever see an astronomical spectrum in your local newspaper, but hopefully a few interested souls will find their way here and realize that there is more to astronomy than taking pretty pictures! If you are one of the few, CLICK HERE to begin the adventure!

A Brief Summary of the Astro Space Shuttle Missions

Bill first came to JHU in 1984 to work on the Hopkins Ultraviolet Telescope project, an ultrviolet sensitive telescope that flew twice on the space shuttle in the 1990s as part of the Astro space shuttle missions. Bill was involved with the preparations for both missions and worked the real time operations at NASA's Marshall Space Flight Center in Huntsville, AL. This description, written like a popular-level magazine article, provides an insider's view into the Astro space shuttle missions, and contains links related information as well. Click here to access this article.

If you find these materials helpful, or if you have suggestions for improvements, I would enjoy hearing from you!

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Last updated: June 2026.

Bill Blair ([email protected])