Upload Kepler transit timing: 295,187 transits, 2,599 KOIs

README.md

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+---
+license: cc-by-4.0
+pretty_name: "Kepler Transit Timing Catalog"
+language:
+  - en
+description: "Holczer et al. (2016) Kepler transit timing catalog — 295,187 individual transit times for 2,599 Kepler Objects of Interest (KOIs), with O-C residuals, durations, and depths."
+task_categories:
+  - tabular-regression
+tags:
+  - space
+  - exoplanets
+  - kepler
+  - transit-timing
+  - ttv
+  - astronomy
+  - open-data
+  - tabular-data
+size_categories:
+  - 100K<n<1M
+configs:
+  - config_name: default
+    data_files:
+      - split: train
+        path: data/kepler_transit_timing.parquet
+    default: true
+---
+
+# Kepler Transit Timing Catalog
+
+*Part of the [Astronomy Datasets](https://huggingface.co/collections/juliensimon/astronomy-datasets-69c24caf2f17e36128946743) collection on Hugging Face.*
+
+Transit timing catalog from Holczer et al. (2016), containing **295,187** individual transit
+mid-times for **2,599** Kepler Objects of Interest (KOIs). Each record includes the
+observed mid-transit time, observed-minus-computed (O-C) residual, transit duration, and
+transit depth with uncertainties.
+
+## Dataset description
+
+Transit timing variations (TTVs) occur when gravitational interactions between planets in a
+multi-planet system cause measurable deviations from a strictly periodic transit schedule.
+Holczer et al. (2016) performed a uniform analysis of all Kepler long-cadence light curves
+to extract individual transit times, producing the most comprehensive Kepler TTV catalog.
+The O-C (observed minus computed) residuals reveal planetary interactions, orbital
+eccentricities, and the presence of additional non-transiting planets.
+
+## Key columns
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `koi` | float64 | Kepler Object of Interest number |
+| `transit_number` | Int32 | Sequential transit number for this KOI |
+| `t_obs_bjd` | float64 | Observed mid-transit time (BJD - 2454833) |
+| `t_obs_err` | float64 | Uncertainty on mid-transit time (days) |
+| `o_c` | float64 | Observed minus computed residual (days) |
+| `o_c_err` | float64 | Uncertainty on O-C residual (days) |
+| `duration_hr` | float64 | Transit duration (hours) |
+| `duration_err` | float64 | Uncertainty on transit duration (hours) |
+| `depth_ppm` | float64 | Transit depth (ppm) |
+| `depth_err` | float64 | Uncertainty on transit depth (ppm) |
+
+## Quick stats
+
+- **295,187** individual transit times
+- **2,599** unique KOIs
+- Median O-C residual: **0.0000** days
+- Median transit depth: **nan** ppm
+- Median transit duration: **nan** hours
+
+## Usage
+
+```python
+from datasets import load_dataset
+
+ds = load_dataset("juliensimon/kepler-transit-timing", split="train")
+df = ds.to_pandas()
+
+# TTVs for a specific KOI
+koi_137 = df[df["koi"] == 137.01].sort_values("transit_number")
+print(f"KOI 137.01: {len(koi_137)} transits")
+
+# Plot O-C diagram
+import matplotlib.pyplot as plt
+plt.errorbar(koi_137["transit_number"], koi_137["o_c"],
+             yerr=koi_137["o_c_err"], fmt=".", ms=3)
+plt.xlabel("Transit number")
+plt.ylabel("O-C (days)")
+plt.title("KOI 137.01 Transit Timing Variations")
+plt.show()
+
+# KOIs with the strongest TTVs (largest O-C scatter)
+ttv_rms = df.groupby("koi")["o_c"].std().sort_values(ascending=False)
+print("Top 10 TTV candidates:")
+print(ttv_rms.head(10))
+```
+
+## Data source
+
+Holczer, T. et al. (2016), "Transit Timing Observations from Kepler. IX. Catalog of
+Transit Timing Measurements of the Long-Cadence Data", ApJS, 225, 9. Accessed via
+[VizieR](https://vizier.cds.unistra.fr/), CDS Strasbourg (J/ApJS/225/9).
+
+## Pipeline
+
+Source code: [juliensimon/space-datasets](https://github.com/juliensimon/space-datasets)
+
+## Citation
+
+```bibtex
+@dataset{kepler_transit_timing,
+  author = {Simon, Julien},
+  title = {Kepler Transit Timing Catalog},
+  year = {2026},
+  publisher = {Hugging Face},
+  url = {https://huggingface.co/datasets/juliensimon/kepler-transit-timing},
+  note = {Based on Holczer et al. (2016) ApJS 225, 9, via VizieR CDS}
+}
+```
+
+## License
+
+[CC-BY-4.0](https://creativecommons.org/licenses/by/4.0/)

data/kepler_transit_timing.parquet

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