C/2017 B3
Not currently visible. Last report 2162 days ago at mag 25.0. Historic peak was mag 15.0. 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
—
J2000
Estimated magnitude
25.0
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
84
Arc unknown
Last observation
2162d ago
Sun, 06 Dec 2020 01:55:12 GMT · COBS consensus
Perihelion
2019-01-29
3.930 au
Peak window
2019-01-26 → 2019-07-28
COBS peak mag 15.0 on 2019-07-25 · perihelion 2019-01-29. Window is those dates ±3 days — not a light-curve fit.
Historic peak
15.0
COBS / analyzed peak 2019-07-25
Catalog ingest
13h ago
Venator last wrote this row 2026-11-06 14:20:22 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
3.930 au
e
0.9980
i
54.30°
Ω
2.31°
ω
285.00°
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/2017 B3 (LINEAR)
Informal: LINEAR
C/2017 B3 · 2026-09-14 18:27:58 UTC → current
Discoverer · parsed-name · 2026-09-14 18:27:58 UTC → current
CCD Observer · MAS01 · 64 reports · last 2162d ago
Visual Observer · WYA · 17 reports · last 2216d ago
CCD Observer · LEH02 · 7 reports · last 2190d ago
CCD Observer · HIL04 · 6 reports · last 3477d ago
CCD Observer · FRI02 · 6 reports · last 2176d ago
Visual Observer · SZA · 3 reports · last 2192d ago
CCD Observer · PAP04 · 1 reports · last 2247d ago
CCD Observer · HAD02 · 1 reports · last 2218d ago
CCD Observer · PAU02 · 1 reports · last 2210d ago
CCD Observer · SHU · 1 reports · last 2236d ago
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.