42P
42P/Neujmin
Not currently visible. Last report 7984 days ago at mag 21.5. Historic peak was mag 20.0. 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
—
J2000
Declination
—
J2000
Estimated magnitude
21.5
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
24
Arc unknown
Last observation
7984d ago
Sun, 07 Nov 2004 11:02:24 GMT · COBS consensus
Perihelion
2026-01-14
2.030 au
Peak window
2026-01-10 → 2026-01-17
COBS peak mag 20.0 on 2026-01-13 · perihelion 2026-01-14. Window is those dates ±3 days — not a light-curve fit.
Historic peak
20.0
COBS / analyzed peak 2026-01-13
Catalog ingest
22m ago
Venator last wrote this row 2026-09-17 01:00:04 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
2.030 au
e
0.5840
i
3.99°
Ω
150.00°
ω
147.00°
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
42P/Neujmin
42P · 2026-09-14 18:27:55 UTC → current
Discoverers
Discoverer · parsed-name · 2026-09-14 18:27:55 UTC → current
Contributors
Visual Observer · SCO01 · 18 reports · last 12085d ago
CCD Observer · NAK01 · 4 reports · last 7984d ago
CCD Observer · TSU02 · 2 reports · last 8044d ago
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.