C/2010 F4
Not currently visible. Last report 6005 days ago at mag 36.8. Historic peak was mag 12.0. 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
36.8
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
4
Arc unknown
Last observation
6005d ago
Thu, 08 Apr 2010 19:55:12 GMT · COBS consensus
Perihelion
2010-04-06
0.614 au
Peak window
2010-03-29 → 2010-04-09
COBS peak mag 12.0 on 2010-04-01 · perihelion 2010-04-06. Window is those dates ±3 days — not a light-curve fit.
Historic peak
12.0
COBS / analyzed peak 2010-04-01
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.
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
0.614 au
e
1.0000
i
89.10°
Ω
237.00°
ω
121.00°
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/2010 F4 (Machholz)
Informal: Machholz
C/2010 F4 · 2026-09-14 18:27:53 UTC → current
Discoverer · parsed-name · 2026-09-14 18:27:53 UTC → current
Visual Observer · DIJ · 2 reports · last 6005d ago
Visual Observer · GON05 · 1 reports · last 6018d ago
Visual Observer · YOS02 · 1 reports · last 6018d ago
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.