C/1997 D1
Not currently visible. Last report 10241 days ago at mag 33.1. Historic peak was mag 12.3. 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
33.1
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
179
Arc unknown
Last observation
10241d ago
Wed, 02 Sep 1998 18:43:11 GMT · COBS consensus
Perihelion
1997-09-27
2.280 au
Peak window
1997-09-24 → 1997-12-10
COBS peak mag 12.3 on 1997-12-07 · perihelion 1997-09-27. Window is those dates ±3 days — not a light-curve fit.
Historic peak
12.3
COBS / analyzed peak 1997-12-07
Catalog ingest
11h ago
Venator last wrote this row 2026-09-16 13:20:16 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
2.280 au
e
1.0000
i
142.00°
Ω
279.00°
ω
185.00°
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/1997 D1 (Mueller)
Informal: Mueller
C/1997 D1 · 2026-09-14 18:27:54 UTC → current
Discoverer · parsed-name · 2026-09-14 18:27:54 UTC → current
Visual Observer · SHA02 · 29 reports · last 10471d ago
Visual Observer · HOR02 · 16 reports · last 10457d ago
CCD Observer · NAK01 · 15 reports · last 10241d ago
Visual Observer · ROQ · 15 reports · last 10469d ago
Visual Observer · HAL · 10 reports · last 10489d ago
Visual Observer · LEH · 10 reports · last 10460d ago
Visual Observer · PEA · 9 reports · last 10489d ago
Visual Observer · BOU · 8 reports · last 10536d ago
Visual Observer · MEY · 7 reports · last 10722d ago
Visual Observer · REN · 6 reports · last 10491d ago
Visual Observer · RES · 6 reports · last 10454d ago
Visual Observer · SAR02 · 4 reports · last 10487d ago
Visual Observer · PLS · 4 reports · last 10487d ago
Visual Observer · MAT08 · 4 reports · last 10467d ago
Visual Observer · BIV · 4 reports · last 10490d ago
Visual Observer · KUT · 4 reports · last 10516d ago
Visual Observer · HAS02 · 4 reports · last 10437d ago
CCD Observer · PRA02 · 3 reports · last 10463d ago
Visual Observer · KAR02 · 3 reports · last 10757d ago
Visual Observer · ZNO · 3 reports · last 10436d ago
Visual Observer · MOR03 · 3 reports · last 10497d ago
Visual Observer · BAR06 · 2 reports · last 10540d ago
Visual Observer · SEA · 2 reports · last 10515d ago
Visual Observer · KYS · 2 reports · last 10544d ago
Visual Observer · MAR02 · 2 reports · last 10764d ago
Visual Observer · YOS04 · 2 reports · last 10490d ago
Visual Observer · BAK01 · 1 reports · last 10784d ago
CCD Observer · MIK · 1 reports · last 10783d ago
Visual Observer · SCO01 · 1 reports · last 10569d ago
Visual Observer · SZE02 · 1 reports · last 10785d ago
Visual Observer · TSU02 · 1 reports · last 10494d ago
Visual Observer · MIY01 · 1 reports · last 10490d ago
CCD Observer · ROQ · 1 reports · last 10428d ago
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.