D ates of heliacally-rising stars -- even if the sighting alignments are similar -- don't remain the same at different places. Because of the earth's axial inclination (shown here) the plane of the ecliptic appears to wander through the fixed stars, making a kind of sine curve throughout the year, as we saw in considering the Lakota sacred star-circle. where over relatively short time periods as things go with the earth and stars, rising and setting times are constant for the fixed stars at each date. But because of the gravitational precession of the earth's polar axis of rotation, the north pole in the celestial globe wanders in a great circle, over some 26,000 years -- and over time periods measured in centuries, this does change what stars can be seen dawn-rising, where, and when.

I n the December, 1977, issue of Technology Review, Eddy wrote "Relying upon the data [which he shows in a graph] I went out on a limb and announced that the astronomical alignments indicated that Moose Mountain Wheel was about 2,000 years old. I don't think that Tom or Alice Kehoe believed me. Nor was I very sure myself.

"T hen, last January [of 1977], I got an excited telephone call from Tom Kehoe. In the summer of 1976, the Kehoes had made further studies at the site. Specifically, they had excavated a part of the central cairn, cutting out a wedge so as not to destroy the structure. At the very bottom of the cairn they had found a flat stone floor; they felt sure they were down to the original construction. Under that, they found charcoal, apparently the ground had been burned off before construction started. There was enough to permit radiocarbon dating. The result, Tom reported, was that this fire had burned 2600 years ago, plus or minus 250 years! This seems close enough to support the astronomical dating of the site, and proves that sometimes we astronomers are lucky."

I t proves something else, too. Judging from the locations of the wheels, and the fact that the oldest ones are in Alberta, it appears that Native astronomy got going in the north more than 2,000 years ago, and spread south to othr tribes from there. At just a few hundred years old, the Bighorn wheel is only a youngster. This isn't saying that all Natives were scientists 2 millenia ago. It seems most likely that the many decades and centuries of makint careful night observations and learning the changing patterns was the work of just a few -- maybe about proportionally the same to the Native population then as astronomers are proportional now to the world's population (a very tiny fraction of people).

S omething almost as exciting happened in 1979. Eddy found no astronomical correlation for Cairn D, either at Medicine Mountain or Moose Mountain, other than to suppose perhaps these south-lying cairns marked a north-south axis on their wheels, which didn't seem necessary. (Polaris gives the best north-south orientation.) In 1979 Florida amateur astronomer Jack H. Robinson made calculations which show that the southerly bright star Fomalhaut -- the mouth of the constellation Pisces (fish) Australianus (south-lying, not the zodiacal "Pisces" of astrology) -- rose heliacally and could be sighted from cairn F, the star-sight at both wheels, through cairns D at both sites. At the Bighorn wheel, this occurred around 1050 to 1450 AD, consistent with Dr. Eddy's dating and a finding by Calgary Archaeologist Michael Wilson that the cairns were probably built considerably earlier than the spokes and rim.

T his dawn-rising of the star Fomalhaut occurred at the Bighorn Wheel from 35 to 33 days before the solstice, when the snow on the way up there would have been pretty deep, but ceremonial watchers probably could have made it up there with snowshoes. The wheel shoulder would be windswept and clear. At Moose Mountain , Fomalhaut's dawn-rising alignment occurred from 600 - 900 AD, several centuries later than Dr. Eddy's date based on the other 3 stars, but just 7 or 8 days before the solstice.

F omalhaut's dawn-rising may actually have occurred exactly in the 2-millenia-old period Dr. Eddy found for the other stars. If you look again at the Moose Mountain diagram, you'll notice that spoke OD is markedly curved along its length. The spoke looks as if it originally may have extended to a cairn more westerly (to the left), perhaps the original sighting cairn for Fomalhaut in the earlier period of Aldebaran, Rigel and Sirius dawn-risings there. Fomalhaut lies more than 30° south of the celestial equator, and is more greatly and quickly affected by equinoctial precession, so while the others persisted in lined-up dawn risings over a couple of centuries, Fomalhaut wouldn't.

I f Robinson's calculations represent how they really built it around 2,000 years ago, perhaps they tried to keep a line on Fomalhaut by moving the cairn east and curving its spoke somewhat. Cairn C, which lies a short way outside the inner circle may also have been moved in an attempt to keep pace with Sirius, also a southerly star more quickly affected by the precessional cycle than north-lying Aldebaran, and Rigel which is only a few degrees south of the celestial equator. Robinson's calculations provide an interesting confirmation of Eddy's, and together they suggest that Aboriginal peoples of the northern plains -- probably only a few of them, the students of the night skies -- had solid and sophisticated astronomical knowledge of their night skies.

M any anthros, Indian "experts" of various persuasions have been crtitical in the 20 years since Dr. Eddy -- not a member of their club -- published his amazing discoveries. Others have said it could be coincidental, these ancient stellar sighting alignments. My then- husband, a physicist specializing in ion-molecule reaction studies, remarked cynically (when I excitedly showed him Eddy's original 1974 article in Science "Oh, astronomers are all nuts anyway. That guy can make all sorts of calcs on any old stars, so he's sure to come up with something that lines up."

R emarking rather cattily that his own research had involved (at that point) making calcs virtually at random about atomic and energetic considerations in hopes of hitting on something from which a valid theory could be derived, I ignored it at the time, and went on to write an article published in 1975 about this exciting discovery for Akwesasne Notes.

S ince then, I have come to believe that many non-Indian "Indian experts" would rather not have any kind of proof that pre-contact aborginal peoples had sophisticated sciences, involving long periods of careful observation and measurement, as well as being highly "civilized" in other ways. They'd rather think of pre-contact Natives as total primitives, who ought to be grateful to have received civilization (along with genocide and loss of land).

F or 2 reasons, then, I'm publishing here an observational table that shows what astronomers concerned with dawn-risings have to work with. There ar only 20 stars of First Magnitude -- the brightest, on a 6-magnitude brightness scale gradient visible to the naked eye -- not all visible at northern latitudes, and at the end of the table they are fairly faint, closer to second than first magnitude.

T his is a relatively small number of "skymarks" to memorize and learn, for learning the night sky. It is quite possible for a people with self-trained memories, though lacking writing to memorize sky patterns and observe their changes over the years, teaching this to apprentices. This would have been a tribal person who would be considered a wise man. (The anthros' and New Agers' word "shaman" seems quite inappropriate), probably with a religious function connected to ceremonial time.

I t's also very useful for today's students and others who want to learn to know the starry night skies without instruments, naked eyes-only. You can easily memorize the First magnitude stars and their constellations. They are excellent anchors for exploring the night sky. Only "first magnitude" stars can be seen to rise briefly in the lightening predawn skies in which all other stars but first magnitudes have disappeared (heliacal or sun-risings). There really are not so many of those as to provide calc-happy folks with unlimited possibilities to make everything come out fo fit some theory. In particular, there were really only 2-3 choices for Richardson to make calc tests on for dawn star alignments on the very southerly cairns at Medicine and Moose Mountains.

H ere they are. My table arranges them in order of magnitudes. Smaller numbers mean brighter stars (and Sirius's magnitude, as the very brightest of the fixed stars, is actually negative). I'm using magnitudes recorded in the late 19th century for naked eye observation, by Richard Hinkley Allen, in Star Names: Their Lore and Meaning, Dover reprint, NY 1963 of the original published in 1899.

W e've been looking up for so long, it's time to look down, at and into th earth. There is something very special about Medicine Mountain, aside from the Wheel located there. You can -- or could, before it bcame a crowded trourist attraction -- feel a power in this lonely high place. Probably that is why the Whel was built there; the others are on raised hills, but this one is uinque in its location, far from any place that any tribespeople were accustomed to go.