C/2011 L3
Not currently visible. Last report 5462 days ago at mag 35.2. Historic peak was mag 15.5. 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
35.2
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
74
Arc unknown
Last observation
5462d ago
Thu, 24 Nov 2011 16:04:48 GMT · COBS consensus
Perihelion
2011-08-12
1.930 au
Peak window
2011-07-24 → 2011-08-15
COBS peak mag 15.5 on 2011-07-27 · perihelion 2011-08-12. Window is those dates ±3 days — not a light-curve fit.
Historic peak
15.5
COBS / analyzed peak 2011-07-27
Catalog ingest
14h ago
Venator last wrote this row 2026-11-06 14:20:19 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
1.930 au
e
0.9990
i
87.40°
Ω
308.00°
ω
27.70°
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).
C/2011 L3 (McNaught)
Informal: McNaught
C/2011 L3 · 2026-09-14 18:27:55 UTC → current
Discoverer · parsed-name · 2026-09-14 18:27:55 UTC → current
Visual Observer · KOU · 19 reports · last 5515d ago
Visual Observer · CER01 · 15 reports · last 5517d ago
CCD Observer · NOV01 · 11 reports · last 5462d ago
Visual Observer · LEH · 8 reports · last 5514d ago
CCD Observer · SHU · 6 reports · last 5526d ago
Visual Observer · HAE · 4 reports · last 5519d ago
CCD Observer · TSU02 · 4 reports · last 5534d ago
Visual Observer · GON05 · 1 reports · last 5608d ago
CCD Observer · YOS02 · 1 reports · last 5549d ago
Visual Observer · PAR03 · 1 reports · last 5585d ago
Visual Observer · YOS04 · 1 reports · last 5568d ago
Visual Observer · IVA03 · 1 reports · last 5571d ago
CCD Observer · KUT · 1 reports · last 5543d ago
Visual Observer · KUT · 1 reports · last 5599d ago
Visual Observer · HAS02 · 1 reports · last 5525d ago
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.