C/2020 R4
Not visible to typical instruments. Current estimate mag 31.8. Historic peak was mag 13.0. 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
31.8
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
302
Arc unknown
Last observation
56d ago
Fri, 11 Sep 2026 23:45:36 GMT · COBS consensus
Perihelion
2021-03-02
1.020 au
Peak window
2021-02-27 → 2021-04-23
COBS peak mag 13.0 on 2021-04-20 · perihelion 2021-03-02. Window is those dates ±3 days — not a light-curve fit.
Historic peak
13.0
COBS / analyzed peak 2021-04-20
Catalog ingest
13h ago
Venator last wrote this row 2026-11-06 14:20:23 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
1.020 au
e
0.9890
i
164.00°
Ω
323.00°
ω
46.50°
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/2020 R4 (ATLAS)
Informal: ATLAS
C/2020 R4 · 2026-09-14 18:28:00 UTC → current
Discoverer · parsed-name · 2026-09-14 18:28:00 UTC → current
Jose Guilherme de Souza Aguiar
Visual Observer · DES01 · 31 reports · last 2022d ago
CCD Observer · LEH02 · 28 reports · last 1947d ago
Visual Observer · COL02 · 16 reports · last 2000d ago
CCD Observer · DEK01 · 16 reports · last 1985d ago
CCD Observer · FRI02 · 15 reports · last 1985d ago
Visual Observer · GON05 · 14 reports · last 1976d ago
CCD Observer · CAR06 · 14 reports · last 1977d ago
Visual Observer · KWI · 13 reports · last 2000d ago
CCD Observer · YOS02 · 11 reports · last 2012d ago
Visual Observer · WYA · 9 reports · last 1980d ago
Visual Observer · DIJ · 9 reports · last 2002d ago
CCD Observer · HAR10 · 9 reports · last 2025d ago
Visual Observer · HAR11 · 8 reports · last 2002d ago
CCD Observer · PAP04 · 7 reports · last 2000d ago
Visual Observer · WOL01 · 7 reports · last 2024d ago
Visual Observer · FIL04 · 7 reports · last 2000d ago
Visual Observer · SCH04 · 6 reports · last 2009d ago
Visual Observer · LAB02 · 6 reports · last 2005d ago
Visual Observer · GOI · 6 reports · last 2026d ago
CCD Observer · MAS01 · 6 reports · last 2006d ago
Visual Observer · TSU02 · 6 reports · last 2008d ago
Visual Observer · MOR03 · 6 reports · last 2004d ago
Visual Observer · BIV · 5 reports · last 1978d ago
Visual Observer · MIY01 · 5 reports · last 2002d ago
CCD Observer · HIL04 · 4 reports · last 2025d ago
Visual Observer · GET · 4 reports · last 2025d ago
Visual Observer · KAR02 · 4 reports · last 2010d ago
Visual Observer · KUT · 4 reports · last 1985d ago
Visual Observer · AMO01 · 3 reports · last 2042d ago
CCD Observer · NOV01 · 3 reports · last 2007d ago
Visual Observer · HER02 · 3 reports · last 2016d ago
Visual Observer · SHA02 · 3 reports · last 2011d ago
Visual Observer · MAT08 · 3 reports · last 2051d ago
Visual Observer · DEC · 3 reports · last 2033d ago
CCD Observer · PAR03 · 3 reports · last 2005d ago
CCD Observer · SHU · 3 reports · last 56d ago
Visual Observer · HAS02 · 3 reports · last 1984d ago
Visual Observer · NOV01 · 2 reports · last 2012d ago
CCD Observer · BRY04 · 2 reports · last 2009d ago
Visual Observer · BUI01 · 2 reports · last 2009d ago
1–40 of 58
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.