Spectral reflectance properties of ureilites
Bibliographic record
Abstract
Abstract– The 0.35–2.6 μm reflectance spectra of 18 ureilites have been examined in order to improve our understanding of the spectral reflectance properties of this meteorite class. Across this spectral range, ureilite spectra are characterized by a steep rise in reflectance over the 0.3 to approximately 0.7 μm range, low overall reflectance (<25%) and weak mafic iron silicate absorption bands in the 1 and 2 μm region. The weakness of these bands and the low reflectance are attributed to the presence of dispersed graphite and related carbonaceous phases, metal, and possibly shock. Wavelength positions of the mafic silicate absorption bands span a range of values, but are consistent with the presence of pyroxene and olivine. Ureilite spectra generally exhibit blue slopes across the 0.7–2.6 μm interval and exhibit many overall similarities to some carbonaceous chondrites. The weak features and spectral diversity of ureilites make reflectance spectroscopy‐based identification of a ureilite parent body challenging. As terrestrial alteration of ureilites is prevalent, spectral studies of falls are most useful for determining the spectral properties of likely parent bodies.
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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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".