Kanzelhöhe Observatory ESA S2P Data Services

UGraz/KSO flare detection

Introduction: The chromosphere of the Sun is an atmospheric layer above the photosphere and below the corona. As the chromosphere is outshined by the photosphere it can only be observed in some very narrow spectral lines, like Hα or CaII. At Kanzelhöhe Observatory the chromosphere is observed in Hα every day - if the local weather conditions permit - from about 8:00 to 16:00 local time.
High-cadence full-disc imaging of the Sun in the H-alpha spectral line provides an important means to identify, locate, and follow the time evolution of solar flares. H-alpha filtergrams are also well suited to identify and locate filaments erupting from the Sun, which are often associated with CMEs. The location of flares and erupting filaments provide important information whether an associated CME eruption is potentially heading toward the direction of Earth, where it may impact about 1 to 6 days later, depending on its initial speed and the solar wind conditions in the interplanetary space.

Technical Information: The Hα images are acquired by a Pulnix TM-4200GE camera with 2048 x 2048 Pixels and 4096 grey levels. The observing cadence of the H-alpha telescope system is 6 seconds. The images are checked for their quality (i.e. sharpness, clouds, intensity distribution) immediately after grabbing. If they meet specific quality criteria, they are processed by an image recognition algorithm called surya that makes use of multilabel segmentation which detects flaring regions and filaments (for further details see Real-time Flare Detection in Ground-Based Hα Imaging at Kanzelhöhe Observatory).

Limitations and caveats of the data:

Observations are not available when the weather is bad.
Standard observation time is between 8:00 and 16:00 local time (CET/CEST).
Even if the panoramic view shows good weather conditions, the image quality can be too low to be processed.
In winter the observations can start later and end earlier due to the low height of the Sun.
The flare detection is updated every minute.
The archive is updated every 5 minutes.
Flares outside 60 degrees from the central meridian are not detected, due to uncertainties with area and intensity determinations near the solar limb.

Use and functionality of the product - latest:
The table on the left side shows all detected flares of the current day. In addition a second table at the right side lists all active regions defined by NOAA/SWPC.

Information on the columns of the event table

Type: Link to a movie of the flare.
Begin: Flare start is defined by time when importance 1 level is reached.
Peak Time: Time of highest flare intensity, in case the flare is still evolving a red label ongoing... is displayed instead of a time stamp.
Position - Active Region: Average position of the centre of gravity in heliographic coordinates. If available an Active Region number is given for the flare location.
> Size: Flare importance class and brilliance (see table below).
update time at the bottom of the table.

Importance classes for flares
S	Subflare	area < 100 · 10^-6 hemispheres
1	Importance 1	100 ≤ area < 250 · 10^-6 hemispheres
2	Importance 2	250 ≤ area < 600 · 10^-6 hemispheres
3	Importance 3	600 ≤ area < 1200 · 10^-6 hemispheres
4	Importance 4 (3+)	area ≥ 1200 · 10^-6 hemispheres

Flare Brilliance		Brightness increase
F	Faint	≥ 3 x quiet chromosphere
N	Normal	≥ 6 x quiet chromosphere
B	Brilliant	≥ 9 x quiet chromosphere

Use and functionality of the product - archive:
At first one has to select the end date of the desired period, by default the current date is set.
The period can be one of the following:

1 day: flares of the same day are shown
1 week: flares of the last 7 days are shown
1 month: flares since one month ago are shown
1 year: flares since one year ago are shown
same month: flares of the current month are shown
same year: flares of the current year are shown
all data: the complete dataset is shown

For each flare following parameters are listed:

Date: date of alert issue in the format yyyy-mm-dd
Flare Start: start time of flare detection
Time of alert: time when alert mail was sent out
Flare type: see below
Active region: active region number where the flare occurred
Link to Alert mail: opens the alert message in a separate window
Link to Movie: opens a flare movie in a separate window

API access to UGraz/KSO flare detection

Introduction

This product can also be used via a Web API (application programming interface) for programmatically accessing the data by requesting specific URL-encoded parameters. The list of mandatory and optional variables for this specific product are included in tables 1 and 2 below:

**Table 1:** Mandatory parameters for API access to UGraz/KSO flare detection.
Variable	Values required for this product
pc	S107
psc	c
component	latest \| archive

**Table 2:** Optional parameters that can be set to refine the query.
Variable	Values
dts_start, dts_end	yyyy-MM-ddTHH:mm:ssZ

Access to the latest data

To access the latest data, the “component” parameter in the address bar needs to be set to “latest”: component = latest. Available at:

https://sso.kso.ac.at/prod/API/index.php?component=latest&pc=S107&psc=c
Returns a JSON containing a list of all flares of the current day.

Format

Dictionary with the datetimestamp as key and begin time, peak time, end time, latitude, longitude, flare type, flare area and active region as values

{
"[datetimestamp]":
{
"begin":[time],"peak":[time],"end":[time],
"latitude":[deg],"longitude":[deg],"type":[deg]
"area":[μhem],"AR":[number]},
}

Example:

https://sso.kso.ac.at/prod/API/index.php?component=latest&pc=S107&psc=c
returns a JSON for the current date YYYY-MM-DD, e.g. for 2020-07-03

    {"2020-07-03":"none"}

or for 2016-05-21

    {
    "2016-05-21T10:58:00Z":{"begin":"10:58:00","peak":"11:00:00","end":"11:07:00",
                            "latitude":"S06","longitude":"W12","flaretype":"SF","area":"76","AR":"12546"},
    "2016-05-21T08:44:00Z":{"begin":"08:44:00","peak":"08:45:00","end":"08:59:00",
                            "latitude":"S08","longitude":"W08","flaretype":"SN","area":"71","AR":"12546"},
    "2016-05-21T08:06:00Z":{"begin":"08:06:00","peak":"08:06:00","end":"08:08:00",
                            "latitude":"S09","longitude":"W14","flaretype":"SF","area":"51","AR":"12546"},
    "2016-05-21T07:15:00Z":{"begin":"07:15:00","peak":"07:16:00","end":"07:18:00",
                            "latitude":"S05","longitude":"W07","flaretype":"SF","area":"54","AR":"12546"},
    "2016-05-21T06:46:00Z":{"begin":"06:46:00","peak":"06:48:00","end":"07:08:00",
                            "latitude":"S08","longitude":"W07","flaretype":"SF","area":"62","AR":"12546"},
    "2016-05-21T06:39:00Z":{"begin":"06:39:00","peak":"06:39:00","end":"06:41:00",
                            "latitude":"S05","longitude":"W09","flaretype":"SF","area":"74","AR":"12546"},
    "2016-05-21T06:30:00Z":{"begin":"06:30:00","peak":"06:30:00","end":"06:33:00",
                            "latitude":"S05","longitude":"W07","flaretype":"SF","area":"59","AR":"12546"},
    "2016-05-21T06:09:00Z":{"begin":"06:09:00","peak":"06:10:00","end":"06:21:00",
                            "latitude":"S08","longitude":"W07","flaretype":"SF","area":"64","AR":"12546"},
    "2016-05-21T05:51:00Z":{"begin":"05:51:00","peak":"05:53:00","end":"05:53:00",
                            "latitude":"S08","longitude":"W07","flaretype":"SF","area":"58","AR":"12546"}}

Access to archive data

To access archive data, the “component” parameter in the address bar needs to be set to “archive”: component = archive. A JSON containing information about the detected flares of the current day is returned as default:
https://sso.kso.ac.at/prod/API/index.php?component=archive&pc=S107&psc=c

In order to select a specific time range, the two following parameters need to be added:
"dts_start" and "dts_end" using the format yyyy-MM-ddTHH:mm:ssZ.
For example:
https://sso.kso.ac.at/prod/API/index.php?component=archive&pc=S107&psc=c&dts_start=2016-02-03T00:00:00Z&dts_end=2016-03-03T00:00:00Z
This returns a JSON containing a list of all detected flares during the selected time period (here from 2016-02-03 at 00:00:00 to 2016-03-03 at 23:59:59).

The data structure of the returned JSON is as follows:

{
"[datetimestamp]":
{
"begin":[time],"peak":[time],"end":[time],
"latitude":[deg],"longitude":[deg],"type":[deg]
"area":[μhem],"AR":[number]},
REPEAT
"[datetimestamp]":
{
"begin":[time],"peak":[time],"end":[time],
"latitude":[deg],"longitude":[deg],"type":[deg]
"area":[μhem],"AR":[number]},
REPEAT
}

For example, the link above returns:

    {
    "2016-02-04T12:51:00Z":{"begin":"12:51:00","peak":"12:51:00","end":"12:53:00",
                            "latitude":"S11","longitude":"E17","flaretype":"SF","area":"60","AR":"0"},
    "2016-02-13T13:39:00Z":{"begin":"13:39:00","peak":"13:43:00","end":"13:56:00",
                            "latitude":"N13","longitude":"W27","flaretype":"SF","area":"53","AR":"12497"},
    "2016-02-13T10:07:00Z":{"begin":"10:07:00","peak":"10:08:00","end":"10:26:00",
                            "latitude":"N13","longitude":"W25","flaretype":"SN","area":"65","AR":"12497"},
    "2016-02-13T08:30:00Z":{"begin":"08:30:00","peak":"08:32:00","end":"08:50:00",
                            "latitude":"N13","longitude":"W24","flaretype":"SN","area":"56","AR":"12497"},
    "2016-02-25T13:02:00Z":{"begin":"13:02:00","peak":"13:03:00","end":"13:06:00",
                            "latitude":"S29","longitude":"E24","flaretype":"SF","area":"53","AR":"0"}}

This web page forms part of the European Space Agency's network of space weather services and service development activities, and is supported under ESA contract number .

For further product-related information or enquiries contact helpdesk. E-mail: helpdesk.swe@esa.int

All publications and presentations using data obtained from this site should acknowledge Kanzelhöhe Observatory for Solar and Environmental Research (KSO) and The ESA Space Safety Programme.

For further information about space weather in the ESA Space Safety Programme see: www.esa.int/spaceweather

Access the ESA Space Weather Service Portal here: swe.ssa.esa.int

At Kanzelhöhe Observatory regular solar observations have been performed for more than 70 years now. The observations are carried out in Whitelight, CaII K and Hα at high cadence. Since 2013 an automatic flare detection system is in operation, that issues flare alerts within a few minutes after a flare starts. The system is improved within this project and additional features like an archive of events and images are added.

The Patrol Instrument, which comprises a set of four telescopes on a common parallactic mounting, is the heart of our observation facilities: it carries the Whitelight telescope, the CaII K telescope, the Hα telescope and a drawing device.
The 2048 x 2048 pixel sized images are recorded at a rate of 10 images per minute and 4096 grey levels. All images are immediately checked for quality and preprocessed, i.e. the FITS header is completed and jpeg images for the live display are prepared.

The top menu navigation bar allows to browse through the products (across the different "Solar Weather" providers) as follows:

Help: Provides more details on the dataproducts, their properties, constraints and access methods, the providing Expert Group as well as this general help on navigation.
Similar products: Navigate to products offering the same type of data but from other providers/instruments.
Related products: Navigate to products that are related in the sense that e.g. one product provides input to the other, or one product is the forecast of the quantity which is measured in the other product.
Latest: Switch to page showing the latest data.
Query: Switch to page offering archive query functionalities.
Email Subscription: Switch to page for email subscription of service.