Defining a non-flare target - manual for the Observer of today (OTD)


The "non-flare target" Space Weather service was established under the SCOSTEP program VarSITI (2014-2018) and is maintained by University of Graz and University of Zagreb. The aim is to target and track coronal holes and filaments, in addition to M-class flares and higher (MFW or GFW) which is covered by other services.

i) Coronal holes (CHs): potentially geoeffective high speed solar wind streams emanate from CHs that are big enough and close enough to the central meridian.
The solar wind speed at Earth, as calculated from CH areas very close to the central meridian (+/-7.5 degrees), needs about 4 days to come to Earth.
ii) Filaments: CMEs are highly likely related to eruptions of filaments.

If criteria #1 or/and #2 listed below are met, define a non-flare target

Criterion #1. There is a CH located at within +/-7.5 degrees in longitude exceeding a ratio area of 0.2 (use UNIGRAZ tool).
Criterion #2. There is a filament located at within +/-30 degrees in longitude (H-alpha imagery).

Daily task of the OTD

Until 14UT write an email to
Subject: "ISEST/MiniMax25 non-flare Target"

If criteria #1 or/and #2 listed above are met, define a non-flare target by putting in the email the following information:
Text: "Potentially geoeffective coronal hole close to the central meridian". Give rough CH coordinates (central point), ratio area, predicted solar wind speed/date.
        "Filament target within +/-30 degrees from central meridian". Choose the most prominent filament(s) and provide center coordinates and time. Define whether it is small or large in extension.

If criteria #1 or/and #2 listed above are NOT met:
Text: "Currently NO non-flare targets, we go with the MM flare-target."

Always put at the end of the email the following:

For flare target see:

For the current overview of space weather see:

To subscribe/unsubscribe your e-mail address visit:
Put the target information also in the following document: Target info and log file


Non-flare targets present at the Sun
----------------No non-flare target present at the Sun--------------

No non-flare target at the Sun

Revision 3: March 25, 2021 by mat
Revision 2: July 3, 2017 by mat
Revision 1: January 30, 2013 by mat