The Lop-sided Spiral Galaxy NGC 247: Clues to a Possible Interaction with NGC 253
Bibliographic record
Abstract
Abstract Observations that span a broad range of wavelengths are used to examine asymmetries in the disk of the nearby late-type spiral galaxy NGC 247. The northern spiral arm is over-luminous at all wavelengths when compared with other parts of the galaxy at similar galactocentric radii, while the density of very luminous red stars in the void that is immediately south of this arm matches that in other parts of the disk at the same galactocentric radius. Two bubbles with spatial extents of many kiloparsecs are identified in the disk, and many of the young stars in the southern disk of NGC 247 are located in the walls of these structures. Dynamical age estimates of these bubbles coincide with the last large-scale star formation event in the nucleus, suggesting that there was large-scale star formation throughout the disk of NGC 247 a few hundred megayears in the past. Morphological similarities are seen with the classical lop-sided galaxy NGC 4027, and it is concluded that NGC 247 is a significantly lop-sided spiral galaxy. The void in the northern disk is then the area between the main body of the disk and the northern arm viewed in projection. The implications of a lop-sided morphology for NGC 247 in the context of interactions with its nearby starburst galaxy companion NGC 253 are discussed.
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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 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 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".