C/1967 Y1
Not currently visible. Last report 21143 days ago at mag 33.6. Historic peak was mag 8.3. 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
33.6
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
302
Arc unknown
Last observation
21143d ago
Mon, 28 Oct 1968 05:16:47 GMT · COBS consensus
Perihelion
1968-01-29
1.680 au
Peak window
1968-01-26 → 1968-02-01
COBS peak mag 8.3 on 1968-01-29 · perihelion 1968-01-29. Window is those dates ±3 days — not a light-curve fit.
Historic peak
8.3
COBS / analyzed peak 1968-01-29
Catalog ingest
11h ago
Venator last wrote this row 2026-09-16 13:20:17 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
1.680 au
e
0.9990
i
129.00°
Ω
254.00°
ω
70.20°
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/1967 Y1 (Ikeya-Seki)
Informal: Ikeya-Seki
C/1967 Y1 · 2026-09-14 18:27:57 UTC → current
Discoverer · parsed-name · 2026-09-14 18:27:57 UTC → current
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Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.