400P
Not currently visible. Last report 2078 days ago at mag 21.5. Historic peak was mag 18.1. 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
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J2000
Declination
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J2000
Estimated magnitude
21.5
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
3
Arc unknown
Last observation
2078d ago
Thu, 07 Jan 2021 18:43:12 GMT · COBS consensus
Perihelion
2027-11-03
2.100 au
Peak window
2027-10-31 → 2027-11-06
COBS peak mag 18.1 on 2027-11-03 · perihelion 2027-11-03. Window is those dates ±3 days — not a light-curve fit.
Historic peak
18.1
COBS / analyzed peak 2027-11-03
Catalog ingest
5m ago
Venator last wrote this row 2026-09-16 23:55:26 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
2.100 au
e
0.4090
i
10.90°
Ω
176.00°
ω
239.00°
a
—
MOID
—
H
—
H0 / n
—
NEO score
—
PHA score
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RMS
—
Elongation
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COBS comet list
okComet Observation Database magnitudes and perihelion data for the full COBS list (active and inactive).
400P/PANSTARRS
400P · 2026-09-14 18:28:00 UTC → current
Discoverer · parsed-name · 2026-09-14 18:28:00 UTC → current
CCD Observer · PAP04 · 1 reports · last 2119d ago
CCD Observer · JAE · 1 reports · last 2078d ago
CCD Observer · CAR06 · 1 reports · last 2125d ago
CCD Observer · CAR09 · 1 reports · last 2125d ago
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.