C/1973 D1
C/1973 D1 (Kohoutek)
Not currently visible. Last report 19464 days ago at mag 40.4. Historic peak was mag 15.1. 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
40.4
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
11
Arc unknown
Last observation
19464d ago
Sun, 03 Jun 1973 02:24:00 GMT · COBS consensus
Perihelion
1973-05-07
1.410 au
Peak window
1973-05-04 → 1973-05-10
COBS peak mag 15.1 on 1973-05-07 · perihelion 1973-05-07. Window is those dates ±3 days — not a light-curve fit.
Historic peak
15.1
COBS / analyzed peak 1973-05-07
Catalog ingest
15h ago
Venator last wrote this row 2026-09-16 13:20:18 UTC
Light curve
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.
Orbital elements
q
1.410 au
e
0.9970
i
122.00°
Ω
165.00°
ω
74.80°
a
—
MOID
—
H
—
H0 / n
—
NEO score
—
PHA score
—
RMS
—
Elongation
—
Reporting sources
COBS comet list
okComet Observation Database magnitudes and perihelion data for the full COBS list (active and inactive).
Name history
C/1973 D1 (Kohoutek)
Informal: Kohoutek
C/1973 D1 · 2026-09-14 18:27:57 UTC → current
Discoverers
Discoverer · parsed-name · 2026-09-14 18:27:57 UTC → current
Contributors
Visual Observer · BOR · 8 reports · last 19464d ago
Visual Observer · KLE01 · 3 reports · last 19492d ago
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.