C/1999 E1
Not currently visible. Last report 9361 days ago at mag 28.3. Historic peak was mag 14.8. 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
28.3
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
42
Arc unknown
Last observation
9361d ago
Wed, 21 Mar 2001 18:00:00 GMT · COBS consensus
Perihelion
1999-02-06
3.900 au
Peak window
1999-01-06 → 1999-02-09
COBS peak mag 14.8 on 1999-01-09 · perihelion 1999-02-06. Window is those dates ±3 days — not a light-curve fit.
Historic peak
14.8
COBS / analyzed peak 1999-01-09
Catalog ingest
14h 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
3.900 au
e
0.7610
i
47.00°
Ω
128.00°
ω
330.00°
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/1999 E1 (Li)
Informal: Li
C/1999 E1 · 2026-09-14 18:27:54 UTC → current
Discoverer · parsed-name · 2026-09-14 18:27:54 UTC → current
CCD Observer · NAK01 · 13 reports · last 9658d ago
Seiichi Yoshida and KenIchi Kadota
CCD Observer · YOS05 · 7 reports · last 9780d ago
CCD Observer · YOS04 · 5 reports · last 9780d ago
CCD Observer · FUK02 · 4 reports · last 9716d ago
Visual Observer · LEH · 4 reports · last 10063d ago
CCD Observer · ORI · 4 reports · last 9361d ago
CCD Observer · CHE03 · 3 reports · last 9654d ago
CCD Observer · BRO08 · 2 reports · last 10071d ago
Visual Observer · HOR02 · 2 reports · last 10095d ago
Visual Observer · HAL · 1 reports · last 10073d ago
CCD Observer · HER02 · 1 reports · last 9419d ago
Visual Observer · HAS02 · 1 reports · last 10096d ago
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.