259P
259P/Garradd
Not currently visible. Last report 1508 days ago at mag 21.3. Historic peak was mag 19.9. 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
20h 29m 22s
J2000
Declination
−45° 03′ 10″
J2000
Estimated magnitude
21.3
Professional survey · COBS consensus
Confidence
33
Class E · priority 60
Observations
1
Arc unknown
Last observation
1508d ago
Wed, 21 Sep 2022 06:30:00 GMT · COBS consensus
Perihelion
2026-08-11
1.810 au
Peak window
2026-08-08 → 2026-08-15
COBS peak mag 19.9 on 2026-08-12 · perihelion 2026-08-11. Window is those dates ±3 days — not a light-curve fit.
Historic peak
19.9
COBS / analyzed peak 2026-08-12
Catalog ingest
20m ago
Venator last wrote this row 2026-11-07 03:30:21 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
1.810 au
e
0.3390
i
15.90°
Ω
51.40°
ω
257.00°
a
2.730 au
MOID
—
H
—
H0 / n
15.5 / 4
NEO score
—
PHA score
—
RMS
—
Elongation
115°
Reporting sources
COBS comet list
okComet Observation Database magnitudes and perihelion data for the full COBS list (active and inactive).
COBS orbits
okOsculating elements and photometric parameters (H0, n) for active comets.
Name history
259P/Garradd
259P · 2026-09-13 22:21:22 UTC → current
Discoverers
Discoverer · parsed-name · 2026-09-13 22:21:22 UTC → current
Contributors
CCD Observer · MAI01 · 1 reports · last 1508d ago
Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.