117P
Not currently visible. Last report 699 days ago at mag 20.1. Historic peak was mag 14.0. Typical backyard telescopes will not show it. HST, JWST, or an 8–10 m class telescope might recover it with a good ephemeris.
Right ascension
—
J2000
Declination
—
J2000
Estimated magnitude
20.1
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
407
Arc unknown
Last observation
699d ago
Sat, 07 Dec 2024 21:50:24 GMT · COBS consensus
Perihelion
2030-11-30
3.110 au
Peak window
2022-07-02 → 2030-12-03
COBS peak mag 14.0 on 2022-07-05 · perihelion 2030-11-30. Window is those dates ±3 days — not a light-curve fit.
Historic peak
14.0
COBS / analyzed peak 2022-07-05
Catalog ingest
3m ago
Venator last wrote this row 2026-11-07 03:00:09 UTC
Brightness over time (V mag)
Gold = reported observations. Steel dashed family = ensemble (nominal / outburst / fade / disruption).
Tail length
Converted to degrees from COBS (d / arcmin / arcsec). Empty until analysis has pulled the archive.
Ensemble is a first-pass H0/n photometric model plus observed samples — not a trained ML forecast yet. The background analyzer walks the catalog one object at a time so COBS is not flooded. Disruption track rises after perihelion to stand in for solar-wind stripping.
q
3.110 au
e
0.2480
i
8.63°
Ω
58.70°
ω
225.00°
a
—
MOID
—
H
—
H0 / n
—
NEO score
—
PHA score
—
RMS
—
Elongation
—
COBS comet list
okComet Observation Database magnitudes and perihelion data for the full COBS list (active and inactive).
117P/Helin-Roman-Alu
117P · 2026-09-14 18:27:52 UTC → current
Discoverer · parsed-name · 2026-09-14 18:27:52 UTC → current
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Jose Guilherme de Souza Aguiar
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1–40 of 48
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.