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ESA SSA SWE Service Page Mockup: SST/arv

Space Surveillance and Tracking – Archive of geomagnetic and solar indices for drag calculation

The service archive of geomagnetic and solar indices for drag calculation is providing the user with values that the service extracts from the database of past values of solar and geomagnetic indices relevant to drag calculation. This includes the following indices:

  • geomagnetic indices ( Kp, Ap, Dst),
  • solar indices (R, F10.7, S10, E10, M10, Y10) and
  • other indices (IG12, IMF).

This service addresses the specific needs of users in the Space Surveillance and Tracking (SST) domain. The database is designed such that automatic access of applications in the SST domain is allowed, which can download requested indices in different specified formats.

Next to the database tool, also other sources of indices are offered through this service.

This service is implemented through a combination of products, tools and alerts which can be found through the following tabs along with expert support provided by the teams constituting the SWE Network. Should you require further guidance in the use of this service, or have specific questions about any aspects of the service presented here, don’t hesitate to contact the Helpdesk.

The service is implemented through the following set of assets:

  • Archive of solar and geomagnetic indices (SGIArv) provided by Space Research Centre Polish Academy of Sciences (SRC);
  • Space Weather bulltetin of the Solar Influences Data Analysis Center (SIDC) provided by the Royal Observatory of Belgium (ROB);
  • Geomagnetic index provided by the German Research Centre for Geosciences (GFZ);
  • Forecast of geomagnetic index provided by the Swedish Institute of Space Physics (IRF Lund);
  • Space Environment Data System (SEDAT) provided by ESA;
  • Nowcast and forecast of geomagnetic indices provided by the British Geological Survey (BGS);
  • Geomagnetic index provided by the Technical University of Denmark (DTU).

This service page is curated by the ESC Ionospheric Weather. For further information, please contact SSCC Help-desk


Currently this service provides the following indices:

  • Daily Total Sunspot Number
  • Daily Observed Flux Density: The 10.7cm Solar Flux is a measurement of the integrated emission at 10.7cm wavelength from all sources present on the disc.
  • Daily Observed Flux Density Adjusted (Flux Density Adjusted for 1 A.U.)
  • Daily Observed Flux Density URSI (URSI Series D Flux, Adj. x 0.9)
  • S10.7 index: S10.7 index is an activity indicator of the integrated 26–34 nm solar irradiance measured by the Solar Extreme-ultraviolet Monitor (SEM) instrument on the NASA/ESA Solar and Heliospheric Observatory (SOHO) satellite.
  • M10.7 index: The M10.7 index is derived from the Mg II core-to-wing ratio that originated from the NOAA series operational satellites, e.g., NOAA-16,-17,-18, which host the Solar Backscatter Ultraviolet (SBUV) spectrometer.
  • Y10.7 index: A composite solar index of the Xb10 index, Lyman-α emission and 81-day cantered smoothed F10.7. Xb10 index and is used to represent the daily energy that is deposited into the mesosphere and lower thermosphere.
  • F30 index: The F30 is the Solar Flux measured by the Nobeyama Radio Observatory, which performs daily measurements of the 30 cm radio flux on an operational 7/365 basis.
  • Definitive Kp index: The global Kp index is obtained as the mean value of the disturbance levels in the two horizontal field components, observed at 13 selected, subauroral stations.
  • Definitive Ap index: The geomagnetic Ap index is derived from the Kp index by averaging the eight values of ap for each day.
  • Final Dst index: The Dst index is an index of magnetic activity derived from a network of near-equatorial geomagnetic observatories that measure the intensity of the globally symmetrical equatorial electrojet.
  • Provisional Dst index
  • IG12 - 12-month-running mean of the ionospheric IG final index: The IG index of solar activity are derived from the monthly median noon foF2 data available from the following thirteen ionospheric observatories. IG12 is 12-month-running mean of the ionospheric IG index.
  • IG12 – provisional
  • Aa_daily index: The daily Aa index is the daily average of eight aa values. Index aa is derived from the K indices measured at two antipodal observatories.
  • Total IMF: The magnetic field carried with the solar wind.
  • IMF Bx: X- component of the magnetic field carried with the solar wind.
  • IMF By: Y-component of the magnetic field carried with the solar wind.
  • IMF Bz: Z-component of the magnetic field carried with the solar wind.
A detailed description of these data sets can be found in the "Metadata Info" of the SGIArv tool.


The database is designed such that automatic access of applications in the SST domain is allowed and they can download requested indices in a required format. The user or application can use a specified API. Next to this, also an user friendly web interface is available. Data can be retrieved in different data formats (e.g. JSON) and image formats (e.g. png, pdf).

Key Products


Solar and Geomagnetic Indices ARchiVe (SGIArv) provided by the Space Research Center PAS is a tool, which has been specifically developed to target the service SST/arv. The current deployment provides 10 indices used in atmospheric models. SGIArv allows the data access via a web interface and also via an API.


For further information, please contact SSCC Help-desk

The following products are associated with this service:

Solar activity indices archive

International Sunspot number
  • R - sunspot number archive
  • SIDC/SILSO International sunspot number
Solar Microwave Index (F10.7)
  • F10.7 archive
  • SIDC 10.7cm Solar radio flux (F10.7) forecast archive
Solar EUV Index (S10.7)
Solar EUV Index (E10.7)
    Solar FUV Index (M10.7)
    Solar X-ray & UV Index (Y10.7)

    Geomagnetic activity indices archive

    Geomagnetic Indices Kp and K
    • K-index from magnetometer stations in north Europe
       DTU K
    • Most recent definitive Kp index
    • Kp and Ap index archive
    • Short term (1 hour) Kp forecast
    • K indices: Hartland, Eskdalemuir and Lerwick
    • 3-hourly Kp-index
    • 3-hourly K(GBI) index
    • Kp - planetary three-hour magnetic index archive
    • Kp, K, Ap, A, Dst archives on SEDAT
    Geomagnetic Index Ap and A
    • Kp and Ap index archive
    • 3-hourly aa-index
    • 3-hourly ap-index
    • Daily Aa index
    • Daily Ap index
    • Ap - planetary daily magnetic index archive
    Geomagnetic Index Dst
    • Forecast of Dst
    • Dst - Disturbance storm time index archive
    • Kp, K, Ap, A, Dst archives on SEDAT

    Other indices

    Interplanetary Magnetic Field (IMF)
    • IMF - Interplanetary magnetic field archive
    Ionospheric Index (IG12)
    • Ionospheric IG index archive

    Tools associated with this service:

    Archive of solar and geomagnetic activity indices for thermospheric drag calculation.

    The AMDA system provides an archive of planetary, solar wind, Earth magnetosphere and ionosphere mission and ground based products. In addition it supports a range of standard models such as magnetic footprints, magnetic fields, solar wind propagation to planets and probes as well as access to external databases of observations and simulations. A key functionality of the system is its embedded plotting, data mining and cataloguing functionalities which are extremely useful in relation to posteriori analysis.

    The H-ESC statistical products tool allows the calculation of statistical parameters and event lists based on long time series of data such as solar wind parameters.

    SEDAT (Space Environment Data System) is a tool for the engineering analysis of spacecraft charged particle environments. The facility provides access to the ODI database containing a large and comprehensive set of data about that environment as measured in-situ by a number of space missions. The user can select a set of space environment data appropriate to the engineering problem under study. SEDAT also offers a set of software tools, which can operate on the data retrieved from the database. These tools allow the user to carry out a wide range of engineering analyses. SEDAT is using a GUI written in Java.

    No alerts are associated with this service.

    This section provides links to web pages or resources that are not part of the SSA Space Weather Network or domain. These sites are not under ESA control and therefore ESA is not responsible for any of the information or links that you may find there.

    Reference documents

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