Readme for Data Source Location - VT SuperDARN

WARNING: All data usage is subject to the Rules of the Road set forth by the respective PI of any given data set. Do not use any data here for scientific publication without first contacting the appropriate PI.

What is this page and how do I use it?

This page allows you to find the location and azimuthal direction of a SuperDARN radar measurement in both geographic and AACGM magentic coordinates. In order to find this information, you need to provide the date of measurement, radar code or FIT/FITACF file, rangegate, and beam number of the measurement you are looking for. If you use a radar code instead of a FIT/FITACF file, you may not get the right answer because certain assumptions will be made about the radar configuration, rather than reading the correct parameters from the data file. The assumptions being made are:

  • fRange = 180 km (Distance to First Range Gate)
  • rSep = 45 km (Separation between range gates)
  • rxRise = 100 (Reciever Rise Time)

In addition to these assumptions, a number of assumptions are made regarding the height of the measurement. To calculate the geographic position of the radar measurement, a virtual height is assumed. This is typically chosen to be 400 km, but the actual value used will be listed in the output file generated by the web page. When converting radar measurements from geographic to AACGM magnetic coordinates, an altitude of 300 km is used for the conversion.

The geographic and geomagnetic coordinates can also be obtained for THEMIS ground-based observatories and some magnetometers in the Step 210 and SAMBA magnetometer chains.


Select the station you wish to find by entering a data source code. The general format of the data source code looks like this:

  • {module id}:{source}:{arguments}

Here are some examples:

  1. fitacf:20080222.0402.0602.bks.fitacf:7,22
  2. radar:gbr:1,18
  3. thmmag:gill:Bx
  4. step210:ktb:By
  5. samba:cer:Bz

Examples 1 and 2: SuperDARN Locator

fitacf:20080222.0402.0602.bks.fitacf:7,22
This will find the location of beam 7, rangegate 22 for the Blackstone radar. If the FITACF file '20080222.0402.0602.bks.fitacf' is available on the server, it will use the fRang, rSep, and rxRise parameters from the FITACF file at the user-specified time. If the file is not found, it will identify the source as Blackstone because of the 'bks' designator in the name.

radar:gbr:1,18
This will find the location of beam 1, rangegate 18 for the Goose Bay Radar using assumed values for fRang, rSep, and rxRise.

Note that 'radar' and 'fitacf' are interchangeable module codes. For a list of 3-letter radar designations, please see this table.

Examples 3-5: THEMIS GBO's, STEP 210, and SAMBA Chain

thmmag:gill:Bx
This will find the geographic and magnetic location of the THEMIS GBO at Gillam. Note that Bx can be replaced with one of the following options:

  • Bx (Magnetic Field Component Pointing toward Magnetic North)
  • By (Magnetic field component pointing 90 degrees East of magnetic North)
  • Bz (Magnetic field component pointing vertically down into the Earth
  • mag (Magnitude of the B field)
  • 0-360 (Horizontal magnetic field component represented as a compass direction relative to magnetic North)

Note that the field component here is assumed to be a user-chosen azimuth relative to magnetic north. Any input that is not an azimuth direction will be reported as bad data (999) in the output file.

step210:ktb:By
This will find the geographic and AACGM magntic locations of station KTB of the Step 210 Magnetometer chain. It will report a magnetic azimuth of 90 degrees.

samba:cer:By
This will find the geographic and AACGM magntic locations of station CER of the SAMBA Magnetometer chain. It will report a magnetic azimuth of 999 (Bad Data), because the Bz component was requested.

All initial geographic positions for THEMIS, STEP210, and SAMBA come from the following lookup tables: