Welcome to the official Sounding of the Ion Energization Region: Resolving Ambiguities (SIERRA) website at Cornell University .

The purpose of the SIERRA mission is to investigate the primary causes of transverse ion acceleration in the topside auroral ionosphere.

The experiment consists of a main payload and two identical sub-payloads separated by hundreds of meters in a triangle configuration within a plane perpendicular to the geomagnetic field. This configuration allows resolving space time ambiguities and provides information on structure at scale lengths of less than 1Km.

SIERRA was successfully launched from the Poker Flat Research Range (PFRR) on January 14th, 2002 at 08:23:05 UT.

Main payload instrumentation:

Cornell University:



Sub-payload instrumentation (each payload):



Select an area of interest:

Principal Investigator:


If you would like to know more, contact Paul Kintner (P.I.) or Eric Klatt
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