My first planetarium software was an old black and white program that ran on a Macintosh Classic computer. I have tried to find a reference for it, but can’t remember its name. As a physics teacher at Juab High School in the small farming town of Nephi, Utah in the early 1990s I had access to a 10” reflecting telescope on a broken down equatorial mount with a burnt out motor. I set up a few evening star parties for students and used the old software to find the locations of the planets and interesting stars and nebulas. We had to move the scope by hand, but it worked all right.
While working through a unit on astrophysics, I came up with a wild idea: to have students create a model of the nearby stars out to about 15 light years. I of course had heard of Alpha Centauri (I grew up watching the original Lost in Space) and had read enough science fiction to know that Tau Ceti and Epsilon Eridani were also nearby stars, but that was about the extent of my knowledge. It became a research quest of mine: to find a table of the nearby stars. I scoured my old college astronomy textbook and it had a table of the brightest stars, but not the closest, although it did list some of them such as Sirius. I looked in university libraries and began to piece a list together. Now this was 1993, and the Internet as we know it now was only beginning. In fact, Tim Berners-Lee developed the World Wide Web system with hypertext about that time, so research had to be done the old way, using the Dewey Decimal System and library index cards.
I finally put together a moderately complete list and developed my own lesson plan activity. Our first attempt used a large styrofoam ball in the center and the stars were beads glued on wooden skewers poked into the ball. Measuring the right ascension and declination was difficult, and the final model was not very accurate or complete. The next year my lesson improved – we hung the stars from the ceiling with black bulletin board paper around and strips of tape for the Vernal Equinox and Celestial Equator, using a primitive sextant to get the angles and proportional spacing correct. We got the stars mostly hung before I realized we had them backwards, so we tore it down and started over. Right Ascension had to be measured to the left, it turned out. It was a great improvement, but the stars were various sized styrofoam balls and didn’t hold up well with repeated use.
Over several decades of teaching and through different schools, I revived the nearby star model every time I taught astronomy. Finding a place to hang it was a challenge. I decided that it would be better to create a hanging platform that could be attached to eyebolts in the ceiling using painted wooden balls on black string and black fabric hung around the model. Much better! I wrote up my lesson plan and submitted it for publication to The Science Teacher, and it was accepted with considerable editing and appeared in the Summer 2014 edition. I even taught this lesson plan at the Jet Propulsion Laboratory through my role as the Educator Facilitator for the NASA Explorer Schools program. The original activity expanded into a complete unit on the nearby stars.
Meanwhile, this full-scale hanging platform model was too big to take on the road, so I designed and built my own tabletop model using foamcore as the hanging platform (now actually the lid of a box) and trigonometry to measure the lengths of the strings for the stars to make the final model more accurate. I took this model to several conferences and presented it, but over the years the tape yellowed and lost its adhesion and there were new stars (brown dwarfs) discovered. The positions of all the stars were more accurately measured by the Hipparcos and Gaia space probes, so that my model was falling apart and needed to be upgraded.
This past summer of 2020, my astrobiology class spent a week building a new tabletop model. We used the Wikipedia article on the nearby starts (so much easier than the first time) and teams created a spreadsheet to calculate the scale distances to hang the stars in the model using trig functions. They drew in scales on the model calculated where to poke the holes in the top foamcore. Other teams measured the strings, or created the labels, or painted the wooden beads. Then teams of three students each came up and hung one star system at a time in the model, starting with Sol and moving outward. We used a scale of one light year equals 2.5 cm. Now I have the model stored in my room and use it for every astronomy class. This summer my astronomy students built scale 3D models of various constellations, which is an easier activity as I only have them hang the most prominent 6-8 stars.
This quest to find out the names and positions of the nearby stars has served me well, as it has led to many opportunities to teach other teachers and students about the night sky. At the time I started this in 1993 no one was really talking about the nearby stars; then the first exoplanets were discovered such as Beta Pictoris b and the 55 Cancri system. Now it has become a hot topic. I have published other lesson plans for how to measure the distances to stars using parallax or my constellation in a box activity previously on this site.
This third edition of Ad Astra will feature articles on the nearby stars and exoplanets, including basic information about the more interesting nearby stars. My astrobiology students last year wrote most of the articles that are included here. Where articles were not completed or the particular star system was not chosen by a student, I will fill in the gaps.
When, as teachers, we get the unavoidable question “Why do we have to learn this stuff?” my answer is always the same: the stars are out there, every night. Students might not be able to see them very well because of light pollution, but I grew up in a dark sky area a long way from any city in the west desert of Utah, and the stars are my friends and I longed to visit them. It would be a shame to go through life without any knowledge of them or how they have influenced humanity from our fundamental mythologies to our current technologies. Ignorance is not bliss. Ignorance is weakness; those that don’t know things can be easily controlled by those that do. I can’t imagine going through life ignorant of the universe around me. One may say that having a knowledge of the stars detracts from their romance and mystery. On the contrary, the more I learn about the stars, the more fascinating they become. I can look at a star and say that I know exoplanets are orbiting it, some in the habitable zone. There could be life up there. I can say that we can’t even see most of the stars (and they don’t show up in planetarium software) because they are too small and dim to be seen by our unaided eyes. I know the tales of the constellations, the ancient myths behind history. I am at home among the stars. “Though my soul may set in darkness, it will rise in perfect light; I have loved the stars too truly to be fearful of the night” (Sarah Williams, 1936, The Old Astronomer to His Pupil).
As a member of a choir at my university, I learned the music to Robert Frost’s poem “Choose Something Like a Star.” The narrator of the poem expresses frustration at how taciturn the star is; it says nothing about what elements it blends, or at what temperature it burns. But Frost was wrong; as much as I like the poem, stars do tell us all about themselves. From their color and spectrum we can tell what elements they blend, what temperature they “burn” (technically fusion), how fast they move, even if they have invisible planets orbiting around them. We have learned to tease a great deal of information out of the light they emit. In the end, the poem comes to peace with the knowledge that the stars are steadfast friends, reliable and ever present, something we can count on. In this world of uncertainty, that means a great deal.
O Star (the fairest one in sight),
We grant your loftiness the right
To some obscurity of cloud—
It will not do to say of night,
Since dark is what brings out your light.
Some mystery becomes the proud.
But to be wholly taciturn
In your reserve is not allowed.
Say something to us we can learn
By heart and when alone repeat.
Say something! And it says, ‘I burn.’
But say with what degree of heat.
Talk Fahrenheit, talk Centigrade.
Use language we can comprehend.
Tell us what elements you blend.
It gives us strangely little aid,
But does tell something in the end.
And steadfast as Keats’ Eremite,
Not even stooping from its sphere,
It asks a little of us here.
It asks of us a certain height,
So when at times the mob is swayed
To carry praise or blame too far,
We may choose something like a star
To stay our minds on and be staid.
Robert Frost, 1916
Here is the completed 3rd edition of our Ad Astra per Educare magazine. I hope you enjoy it and share it. This post has been my editorial article taken from the magazine. Future blog posts will include the articles by my students and the longer feature article on the nearby stars. Things have certainly come a long way from that initial newsletter I had my digital media students create using Quark XPress way back in 2000. We’ve found out so much more about the nearby stars since then including whole new stars and 13 or so exoplanets within 13 light years of Earth. More will be discovered. It is nice to see this topic of the nearby stars finally coming into its own.