Modelling the light curve of ‘Oumuamua: evidence for torque and disc-like shape
Why this work is in the frame
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Bibliographic record
Abstract
ABSTRACT We present the first attempt to fit the light curve of the interstellar visitor ‘Oumuamua using a physical model that includes optional torque. We consider both conventional (Lommel–Seeliger triaxial ellipsoid) and alternative (‘black-and-white ball’, ‘solar sail’) brightness models. With all the brightness models, some torque is required to explain the timings of the most conspicuous features – deep minima – of the asteroid’s light curve. Our best-fitting models are a thin disc (aspect ratio 1:6) and a thin cigar (aspect ratio 1:8) that are very close to being axially symmetric. Both models are tumbling and require some torque that has the same amplitude in relation to ‘Oumuamua’s linear non-gravitational acceleration as in Solar system comets whose dynamics is affected by outgassing. Assuming random orientation of the angular momentum vector, we compute probabilities for our best-fitting models. We show that cigar-shaped models suffer from a fine-tuning problem and have only 16 per cent probability to produce light-curve minima as deep as the ones present in ‘Oumuamua’s light curve. Disc-shaped models, on the other hand, are very likely (at 91 per cent) to produce minima of the required depth. From our analysis, the most likely model for ‘Oumuamua is a thin disc (slab) experiencing moderate torque from outgassing.
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Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 it