Learn about space weather
The key concepts to read a solar activity bulletin, anticipate an aurora and follow the ongoing solar cycle. Written by the Pulsar team, cross-checked against NOAA, GFZ Potsdam and NASA sources.
- Foundations
What is an aurora?
An aurora borealis is a coloured glow produced in the upper atmosphere when solar-wind particles, channelled by Earth's magnetic field, stri...
8 min read - Indices
The Kp index: how to read and use it
The Kp index is a global measure of geomagnetic activity, published every 3 hours by GFZ Potsdam (Germany). It ranges from 0 (calm sky) to 9...
7 min read - Events
Solar storms: from CMEs to auroras
A solar storm is a major disturbance of the space environment triggered by a flare or a coronal mass ejection. It takes 15 minutes to 3 days...
9 min read - Foundations
The solar wind: a plasma that bathes Earth
The solar wind is a plasma mostly of protons and electrons, continuously emitted by the solar corona at an average 400 km/s. It carries the ...
7 min read - Foundations
The solar cycle: an 11-year heartbeat
The Sun alternates periods of calm and intense activity on an ~11-year cycle. We are currently near the peak of cycle 25, which has already ...
7 min read