C/1991 R1
Not visible to typical instruments. Current estimate mag 36.0. Historic peak was mag 22.4. Visual and most CCD amateur setups will not see it. Space telescopes or large ground telescopes are the remaining path.
Right ascension
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J2000
Declination
—
J2000
Estimated magnitude
36.0
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
0
Arc unknown
Last observation
Not in feed
COBS consensus does not publish an observer timestamp. Catalog ingested 2d ago.
Perihelion
1990-11-03
7.060 au
Peak window
1990-09-03 → 1990-11-06
COBS peak mag 22.4 on 1990-09-06 · perihelion 1990-11-03. Window is those dates ±3 days — not a light-curve fit.
Historic peak
22.4
COBS / analyzed peak 1990-09-06
Catalog ingest
2d ago
Venator last wrote this row 2026-09-14 20:00:20 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.
No tail measures stored yet for this object.
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
7.060 au
e
0.9990
i
104.00°
Ω
150.00°
ω
149.00°
a
—
MOID
—
H
—
H0 / n
—
NEO score
—
PHA score
—
RMS
—
Elongation
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COBS comet list
okComet Observation Database magnitudes and perihelion data for the full COBS list (active and inactive).
C/1991 R1 (McNaught-Russell)
Informal: McNaught-Russell
C/1991 R1 · 2026-09-14 18:28:00 UTC → current
Discoverer · parsed-name · 2026-09-14 18:28:00 UTC → current
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.