C/1975 E1
Not currently visible. Last report 18789 days ago at mag 37.2. 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
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J2000
Declination
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J2000
Estimated magnitude
37.2
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
1
Arc unknown
Last observation
18789d ago
Wed, 09 Apr 1975 07:40:48 GMT · COBS consensus
Perihelion
1975-04-27
1.180 au
Peak window
1975-04-24 → 1975-04-30
COBS peak mag 11.0 on 1975-04-27 · perihelion 1975-04-27. Window is those dates ±3 days — not a light-curve fit.
Historic peak
11.0
COBS / analyzed peak 1975-04-27
Catalog ingest
11h ago
Venator last wrote this row 2026-09-16 13:20:18 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.
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
1.180 au
e
1.0000
i
55.10°
Ω
158.00°
ω
264.00°
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/1975 E1 (Bradfield)
Informal: Bradfield
C/1975 E1 · 2026-09-14 18:27:57 UTC → current
Discoverer · parsed-name · 2026-09-14 18:27:57 UTC → current
Visual Observer · JON · 1 reports · last 18789d ago
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.