Notice: AMPERE processing during transition to Iridium NEXT.
It is very exciting that the second generation of Iridium satellites, Iridium NEXT ( https://www.iridiumnext.com/), are in the process of being launched. The first launch of ten NEXT satellites was on 14 January 2017 and the 41st through 50th NEXT satellites were launched on 29 March 2018. That means that 2/3 of the new constellation is already in place, and the new satellites are all performing well!
The Iridium NEXT satellites promise even better input data for AMPERE. In the short term, we are working to ingest and perform the initial processing and calibration of NEXT data. If you thought that in-flight calibration of four space magnetometers was hard (e.g., Cluster and MMS), imagine handling a total of 75! So please bear with us as we work to make this exciting new dataset as high quality as possible.
Beginning in January 2017, you may notice more `gray' satellites in the browser and summary graphics, indicating a lack of data from the original constellation (Block 1). This reflects the replacement within the constellation of Block 1 satellites with NEXT satellites, which we are not yet including in our processing. This leads to a gradual degradation of the data products so that data from January 2017 through September 2017 should be used with caution. The user should pay particular attention to whether the time or region of interest are mostly actual data or delayed data (plotted in gray). Because the AMPERE inversions require a minimum spatial coverage (roughly half of the satellites in each orbit plane, at the least), we have had to pause the spherical harmonic inversions and derived product generation as of 20 September 2017 as we work to integrate the NEXT data (19 September 2017 is the most recent day processed).
When we have our processing of the NEXT data in place, we will re-process all of the AMPERE products from January 2017 forward so these data WILL be available - things are just under construction for a bit longer.
If you have any questions, don't hesitate to contact us. We're always glad to help.