P/2007 H1
Not currently visible. Last report 1821 days ago at mag 19.1. Historic peak was mag 13.2. 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
19.1
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
118
Arc unknown
Last observation
1821d ago
Tue, 21 Sep 2021 20:24:00 GMT · COBS consensus
Perihelion
2021-09-13
2.300 au
Peak window
2021-09-03 → 2021-09-16
COBS peak mag 13.2 on 2021-09-06 · perihelion 2021-09-13. Window is those dates ±3 days — not a light-curve fit.
Historic peak
13.2
COBS / analyzed peak 2021-09-06
Catalog ingest
15m ago
Venator last wrote this row 2026-09-16 22:00:03 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
2.300 au
e
0.3760
i
11.90°
Ω
144.00°
ω
202.00°
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).
P/2007 H1 (McNaught)
Informal: McNaught
P/2007 H1 · 2026-09-13 22:21:22 UTC → current
Discoverer · parsed-name · 2026-09-13 22:21:22 UTC → current
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Jose Guilherme de Souza Aguiar
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Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.