SCARS ON THE SHIELD: CARLYLE BEALS, PETER MILLMAN, AND THE BEGINNING OF THE CANADIAN METEORITE CRATER PROGRAM, 1950–1960
Bibliographic record
Abstract
ABSTRACT When Peter Millman, an astronomer at the Dominion Observatory in Ottawa, read Ralph Baldwin’s 1949 book The Face of the Moon , he excitedly brought it to the attention of the Observatory’s recently-appointed Director, Carlyle Beals. Baldwin’s book argued that the Moon’s numerous circular features were not of volcanic origin, but were due to meteorite impacts, and that the Earth should similarly have an abundance of meteorite impact scars. Beals and Millman decided to test Baldwin’s arguments, and Beals initiated an innovative program at the Observatory to search for meteorite craters on the Canadian Shield. By the mid-1960s, ten craters had been discovered in Canada. Today, 190 meteorite craters have been confirmed worldwide, with nearly one-sixth of them in Canada. Investigations of the Canadian craters, employing gravity, magnetic, seismic, and diamond drilling studies, became a model for all future crater studies, and brought international attention to Canadian scientists.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.004 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.002 |
| Science and technology studies | 0.019 | 0.008 |
| Scholarly communication | 0.003 | 0.002 |
| Open science | 0.001 | 0.002 |
| Research integrity | 0.002 | 0.004 |
| Insufficient payload (model declined to judge) | 0.006 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".