C/2025 Q3
Not visible to typical instruments. Current estimate mag 19.8. Historic peak was mag 17.4. Visual and most CCD amateur setups will not see it. Space telescopes or large ground telescopes are the remaining path.
Right ascension
—
J2000
Declination
—
J2000
Estimated magnitude
19.8
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
72
Arc unknown
Last observation
179d ago
Sun, 22 Mar 2026 10:33:36 GMT · COBS consensus
Perihelion
2026-02-25
2.110 au
Peak window
2026-02-22 → 2026-02-28
COBS peak mag 17.4 on 2026-02-25 · perihelion 2026-02-25. Window is those dates ±3 days — not a light-curve fit.
Historic peak
17.4
COBS / analyzed peak 2026-02-25
Catalog ingest
2m ago
Venator last wrote this row 2026-09-17 00:00:08 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
2.110 au
e
0.9970
i
90.20°
Ω
233.00°
ω
218.00°
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/2025 Q3 (ATLAS)
Informal: ATLAS
C/2025 Q3 · 2026-09-13 22:21:23 UTC → current
Discoverer · parsed-name · 2026-09-13 22:21:23 UTC → current
CCD Observer · PEA · 26 reports · last 222d ago
CCD Observer · MAT08 · 7 reports · last 179d ago
CCD Observer · KOU · 6 reports · last 238d ago
CCD Observer · DEK01 · 6 reports · last 234d ago
CCD Observer · LEH02 · 5 reports · last 194d ago
CCD Observer · HIL04 · 4 reports · last 245d ago
CCD Observer · MAS01 · 4 reports · last 192d ago
CCD Observer · SRE01 · 4 reports · last 272d ago
CCD Observer · FRI02 · 3 reports · last 269d ago
CCD Observer · CAR06 · 2 reports · last 248d ago
CCD Observer · BRY04 · 1 reports · last 264d ago
CCD Observer · PAP04 · 1 reports · last 203d ago
CCD Observer · SOL02 · 1 reports · last 282d ago
CCD Observer · YOS02 · 1 reports · last 306d ago
CCD Observer · LOM01 · 1 reports · last 338d ago
CCD Observer · OLA · 1 reports · last 203d ago
CCD Observer · YUS · 1 reports · last 270d ago
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.