C/2015 G2
Not currently visible. Last report 3915 days ago at mag 32.6. Historic peak was mag 8.8. 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
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J2000
Estimated magnitude
32.6
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
153
Arc unknown
Last observation
3915d ago
Mon, 28 Dec 2015 20:24:00 GMT · COBS consensus
Perihelion
2015-05-21
0.768 au
Peak window
2015-05-17 → 2015-05-24
COBS peak mag 8.8 on 2015-05-20 · perihelion 2015-05-21. Window is those dates ±3 days — not a light-curve fit.
Historic peak
8.8
COBS / analyzed peak 2015-05-20
Catalog ingest
11h ago
Venator last wrote this row 2026-09-16 13:20:17 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
0.768 au
e
1.0000
i
147.00°
Ω
110.00°
ω
257.00°
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/2015 G2 (MASTER)
Informal: MASTER
C/2015 G2 · 2026-09-14 18:27:56 UTC → current
Discoverer · parsed-name · 2026-09-14 18:27:56 UTC → current
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Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.