Comet atlas
A census of CO₂ released by comets, measured in SPHEREx frames. Each point is one comet at the epoch of its census, with the 16–84% range of the production rate Q.
20 comets · 17 detected · 2 with systematics · 1 marginal · 0 not detected
Read these first
- This is a census by pass, not a real-time monitor: SPHEREx revisits each comet only a few times a year, and public data lag by weeks.
- Q is proportional to the outflow speed. Assuming a speed of 0.50 instead of 0.85 r_h^−0.5 km/s lowers every Q by about 40%: treat this as a systematic on top of the plotted range.
- Beyond 10 au the band flux is too small for a trustworthy Q. Those points are marked and should not be interpreted.
- “With systematics” means a band is present (S/N ≥ 5) but the band model fits poorly (χ²ᵣ ≥ 50): the Q shown is not trusted at its quoted precision.
Q(CO₂) against heliocentric distance
Select a point or a row to see its numbers.
Census table
| Comet | r_h (au) | Δ (au) | Q(CO₂) 16–50–84% (s⁻¹) | S/N det. | σ_F/F | n_core | χ²ᵣ | Status | CO | H₂O |
|---|---|---|---|---|---|---|---|---|---|---|
| 1.02 | 0.17 | 5.44 × 10²³ · 7.61 × 10²³ · 1.03 × 10²⁴ | 4.1 | 0.243 | 1 | 15.8 | Marginal | no data | — | |
| 1.78 | 1.50 | 2.21 × 10²⁵ · 2.73 × 10²⁵ · 3.34 × 10²⁵ | 27.1 | 0.043 | 5 | 2.1 | Detected | upper limit | detection3.60 × 10²⁶ | |
| 2.01 | 1.67 | 3.06 × 10²⁵ · 3.79 × 10²⁵ · 4.65 × 10²⁵ | 24.7 | 0.049 | 4 | 6.9 | Detected | upper limit | no coverage | |
| 2.06 | 1.76 | 4.15 × 10²⁵ · 1.00 × 10²⁶ · 1.70 × 10²⁶ | 14.2 | 0.591 | 0 | 4.1 | Detected | no coverage | upper limit | |
| 2.11 | 1.95 | 1.70 × 10²⁷ · 2.09 × 10²⁷ · 2.55 × 10²⁷ | 50.0 | 0.020 | 1 | 71.6 | With systematics | candidateCO/CO₂ 0.7 | no coverage | |
| 2.13 | 1.87 | 6.23 × 10²⁴ · 8.21 × 10²⁴ · 1.07 × 10²⁵ | 5.7 | 0.182 | 3 | 2.3 | Detected | upper limit | detection1.32 × 10²⁶ | |
| Details | 2.15 | 1.81 | 2.78 × 10²⁷ · 3.42 × 10²⁷ · 4.18 × 10²⁷ | 41.1 | 0.025 | 2 | 185.2 | With systematics | candidateCO/CO₂ 1.5 | no coverage |
| 2.16 | 1.79 | 1.51 × 10²⁶ · 1.86 × 10²⁶ · 2.27 × 10²⁶ | 28.0 | 0.036 | 3 | 19.2 | Detected | upper limit | detection1.29 × 10²⁷ | |
| 2.18 | 1.88 | 1.07 × 10²⁶ · 1.38 × 10²⁶ · 1.78 × 10²⁶ | 11.7 | 0.157 | 0 | 2.0 | Detected | upper limit | no coverage | |
| 2.21 | 1.99 | 2.06 × 10²⁶ · 2.53 × 10²⁶ · 3.09 × 10²⁶ | 42.4 | 0.024 | 10 | 38.7 | Detected | upper limit | upper limit | |
| 2.45 | 2.28 | 2.06 × 10²⁶ · 2.54 × 10²⁶ · 3.11 × 10²⁶ | 22.5 | 0.044 | 1 | 19.4 | Detected | no data | no coverage | |
| 3.45 | 3.35 | 2.52 × 10²⁶ · 3.10 × 10²⁶ · 3.79 × 10²⁶ | 35.2 | 0.031 | 2 | 4.8 | Detected | no data | — | |
| 3.57 | 3.50 | 8.92 × 10²⁶ · 1.10 × 10²⁷ · 1.34 × 10²⁷ | 53.3 | 0.019 | 1 | 4.7 | Detected | upper limit | — | |
| 3.83 | 3.73 | 4.31 × 10²⁶ · 5.30 × 10²⁶ · 6.48 × 10²⁶ | 63.7 | 0.019 | 2 | 1.5 | Detected | upper limit | — | |
| 3.93 | 3.59 | 7.11 × 10²⁶ · 8.75 × 10²⁶ · 1.07 × 10²⁷ | 37.9 | 0.028 | 1 | 2.2 | Detected | no data | — | |
| 4.36 | 4.30 | 3.89 × 10²⁶ · 4.79 × 10²⁶ · 5.87 × 10²⁶ | 30.3 | 0.036 | 3 | 4.4 | Detected | upper limit | — | |
| 4.63 | 4.58 | 9.59 × 10²⁵ · 1.24 × 10²⁶ · 1.58 × 10²⁶ | 7.5 | 0.145 | 2 | 2.7 | Detected | upper limit | — | |
| 5.49 | 4.97 | 4.20 × 10²⁶ · 5.20 × 10²⁶ · 6.40 × 10²⁶ | 30.6 | 0.053 | 1 | 1.8 | Detected | no coverage | — | |
| Details | 6.30 | 6.20 | 8.29 × 10²⁶ · 1.03 × 10²⁷ · 1.27 × 10²⁷ | 20.3 | 0.053 | 3 | 9.0 | Detected | detectionCO/CO₂ 43.8 | — |
| Far: unreliable | 14.97 | 14.91 | 1.35 × 10²⁷ · 1.75 × 10²⁷ · 2.24 × 10²⁷ | 6.9 | 0.145 | 7 | 10.2 | Detected | upper limit | — |
Measured, then checked
Two results are compared with published values. A measurement that falls inside the published range is consistent with it; it is not an independent confirmation.
| Result | This work | Published | Check |
|---|---|---|---|
| 3I/ATLAS · CO₂ · 2025-08 | 1.17 × 10²⁷ s⁻¹ | 9.40 × 10²⁶–1.60 × 10²⁷ | inside the published range |
| statistical ±3.00 × 10²⁵; χ²ᵣ 27.5; 16–84% 8.60 × 10²⁶–1.38 × 10²⁷ 16–84% interval from the research notes, not re-run in this build. Lisse et al. 2025, RNAAS, arXiv:2508.15469 (0.94e27, preliminary); Lisse et al. 2026, ApJL 1000, L52, arXiv:2512.07318 (1.6e27 +/- 0.16e27) | |||
| 29P/Schwassmann-Wachmann · CO · 2025-12 | 4.50 × 10²⁸ s⁻¹ | 2.90 × 10²⁸–5.60 × 10²⁸ | inside the published range |
| χ²ᵣ 127.3; CO/CO₂ 43.8 [36.6–51.9] Bockelee-Morvan et al. 2022 (IRAM, 2.9-5.6e28); quiescent 1.8e28 (Festou et al. 2001) | |||
Pending: 3I/ATLAS H₂O in August 2025 is not shown. no retained CSV or reproducible script output for the August 2025 H2O fit; the guide cites 4.0e26 against 3.2e26 (Lisse et al. 2026) but it is not exported until re-derived
Method in brief
CO₂ ν₃ band model with P and R branches over a sky-subtracted spectrum; Q from a Haser parent model with a Monte Carlo over flux, calibration, g-factor, lifetime and speed. Detection requires S/N ≥ 5 and χ²ᵣ < 50. Percentiles are 16/50/84.
detected: S/N_det >= 5 and chi2_red < 50; with_systematics: S/N_det >= 5 and chi2_red >= 50; marginal: 3 <= S/N_det < 5; not_detected: S/N_det < 3
Data files: 3I_aug2025_bandfits.csv, 3I_aug2025_spectrum.csv, co2_census_physical.csv, co_census_final.csv, h2o_census.csv, q_vs_aperture.csv
Download the atlas data (JSON)