C/2005 A1
Not currently visible. Last report 7675 days ago at mag 35.4. Historic peak was mag 11.0. 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
35.4
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
187
Arc unknown
Last observation
7675d 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 11.0 on 2005-03-18 · perihelion 2005-03-31. Window is those dates ±3 days — not a light-curve fit.
Historic peak
11.0
COBS / analyzed peak 2005-03-18
Catalog ingest
13h ago
Venator last wrote this row 2026-11-06 14:20:18 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
Visual Observer · PEA · 22 reports · last 7848d ago
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CCD Observer · SRB · 14 reports · last 7680d ago
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Visual Observer · GON05 · 9 reports · last 7740d ago
Visual Observer · SHU · 9 reports · last 7724d ago
Visual Observer · BOU · 8 reports · last 7734d ago
Visual Observer · DIJ · 7 reports · last 7734d ago
Visual Observer · YOS04 · 7 reports · last 7683d ago
Visual Observer · NEV · 7 reports · last 7737d ago
Visual Observer · JON · 6 reports · last 7907d ago
Visual Observer · BAR06 · 6 reports · last 7697d ago
CCD Observer · HOR02 · 6 reports · last 7680d ago
Visual Observer · MAR02 · 5 reports · last 7706d ago
Visual Observer · LEH · 5 reports · last 7730d ago
Visual Observer · KUT · 5 reports · last 7732d ago
Visual Observer · ROB06 · 5 reports · last 7907d ago
Visual Observer · POW01 · 4 reports · last 7732d ago
Visual Observer · MAT08 · 4 reports · last 7848d ago
Visual Observer · PAR03 · 4 reports · last 7738d ago
Visual Observer · GUZ · 4 reports · last 7675d ago
Visual Observer · TOT03 · 4 reports · last 7707d ago
Visual Observer · HAS02 · 3 reports · last 7680d ago
CCD Observer · OHS · 3 reports · last 7763d ago
Visual Observer · LAB02 · 2 reports · last 7734d ago
Visual Observer · SAN04 · 2 reports · last 7706d ago
Visual Observer · COO02 · 2 reports · last 7893d ago
CCD Observer · KAL02 · 2 reports · last 7699d ago
Visual Observer · SOU01 · 2 reports · last 7910d ago
Visual Observer · URB01 · 2 reports · last 7784d ago
CCD Observer · NAK01 · 1 reports · last 7959d ago
CCD Observer · KUO · 1 reports · last 7728d ago
Visual Observer · SCH18 · 1 reports · last 7764d ago
Visual Observer · CER01 · 1 reports · last 7696d ago
Visual Observer · HOR02 · 1 reports · last 7731d ago
Visual Observer · YOS02 · 1 reports · last 7960d ago
Visual Observer · TSU02 · 1 reports · last 7734d ago
CCD Observer · TSU02 · 1 reports · last 7963d ago
Visual Observer · MIY01 · 1 reports · last 7959d ago
1–40 of 41
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.