Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock ( ) or https://
means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
The AE index is derived from geomagnetic variations in the horizontal component observed at selected (10-13) observatories along the auroral zone in the northern hemisphere. To normalize the data...
data.gov
An official website of the GSA's Technology Transformation Services