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Venator

Early warning for newly discovered comets and unconfirmed objects.

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128P

128P/Shoemaker-Holt

CometClass Ecatalogued
Northern hemisphere

Not visible to typical instruments. Current estimate mag 20.9. Visual and most CCD amateur setups will not see it. Space telescopes or large ground telescopes are the remaining path.

Active comet in COBS

JSONCSV

Right ascension

06h 57m 07s

J2000

Declination

+18° 50′ 28″

J2000

Estimated magnitude

20.9

Professional survey · COBS consensus

Confidence

33

Class E · priority 60

Observations

59

80.00 d arc

Last observation

59d ago

Tue, 08 Sep 2026 19:57:21 GMT · COBS consensus

Perihelion

2026-07-17

3.040 au

Peak window

2026-07-14 → 2026-12-22

COBS peak mag 20.7 on 2026-12-19 · perihelion 2026-07-17. Window is those dates ±3 days — not a light-curve fit.

Historic peak

20.7

COBS / analyzed peak 2026-12-19

Catalog ingest

22m ago

Venator last wrote this row 2026-11-07 03:00:09 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.

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

3.040 au

e

0.3220

i

4.37°

Ω

214.00°

ω

211.00°

a

4.480 au

MOID

—

H

—

H0 / n

8.5 / 4

NEO score

—

PHA score

—

RMS

—

Elongation

105°

Reporting sources

  • COBS comet list

    ok

    Comet Observation Database magnitudes and perihelion data for the full COBS list (active and inactive).

  • COBS orbits

    ok

    Osculating elements and photometric parameters (H0, n) for active comets.

Name history

  • 128P/Shoemaker-Holt

    128P · 2026-09-08 02:09:56 UTC → current

Discoverers

  • Shoemaker-Holt

    Discoverer · parsed-name · 2026-09-08 17:27:23 UTC → current

Contributors

Pips are observation weight on this object (log of report count). Hover for catalog-wide weight.