C/2005 A1
Not currently visible. Last report 7624 days ago at mag 35.3. Historic peak was mag 7.8. 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
35.3
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
187
Arc unknown
Last observation
7624d ago
Tue, 01 Nov 2005 20:52:48 GMT · COBS consensus
Perihelion
2005-03-31
0.934 au
Peak window
2005-03-15 → 2005-04-03
COBS peak mag 7.8 on 2005-03-18 · perihelion 2005-03-31. Window is those dates ±3 days — not a light-curve fit.
Historic peak
7.8
COBS / analyzed peak 2005-03-18
Catalog ingest
2d ago
Venator last wrote this row 2026-09-14 20:00:16 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
0.934 au
e
1.0000
i
74.90°
Ω
356.00°
ω
272.00°
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).
C/2005 A1 (LINEAR)
Informal: LINEAR
C/2005 A1 · 2026-09-14 18:27:54 UTC → current
Discoverer · parsed-name · 2026-09-14 18:27:54 UTC → current
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Visual Observer · PAR03 · 4 reports · last 7687d ago
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CCD Observer · KAL02 · 2 reports · last 7648d ago
Visual Observer · SOU01 · 2 reports · last 7859d ago
Visual Observer · URB01 · 2 reports · last 7733d ago
CCD Observer · NAK01 · 1 reports · last 7908d ago
CCD Observer · KUO · 1 reports · last 7677d ago
Visual Observer · SCH18 · 1 reports · last 7713d ago
Visual Observer · CER01 · 1 reports · last 7645d ago
Visual Observer · HOR02 · 1 reports · last 7680d ago
Visual Observer · YOS02 · 1 reports · last 7909d ago
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CCD Observer · TSU02 · 1 reports · last 7912d ago
Visual Observer · MIY01 · 1 reports · last 7908d ago
1–40 of 41
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.