Chaser Pro unlocks the full 24-hour solar wind history — Bt/Bz, density, speed, and temperature, the same way real space weather forecasters watch it.
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Last 24 hours, updated every minute as new data arrives.
New to solar wind data? These four measurements are what real space weather forecasters watch to predict aurora, minutes to hours before it actually happens. The short version: watch Bz for a sharp move south (negative), and watch for density and speed spiking together, those are the two clearest signs a storm is arriving or intensifying.
IMF (nT) — Bt / Bz
How to read this: Bz is the one that matters most. When Bz turns negative (dips below the zero line), Earth's magnetic shield opens up and lets solar wind energy pour in, that's what actually drives aurora. The more negative, the better your odds. Bt is the total field strength, it sets the ceiling for how negative Bz could possibly get.
Density (p/cm³)
How to read this: This counts how tightly packed the solar wind particles are. A sudden spike often means a CME's leading edge or a shock front has just arrived, worth watching alongside speed for confirmation.
Speed (km/s)
How to read this: Normal solar wind runs around 300-400 km/s. Faster speeds, especially above 500-600 km/s, carry more energy into Earth's magnetic field and generally mean a stronger, more active night.
Temperature (K)
How to read this: A sudden jump in temperature, especially at the same moment density and speed also jump, is a classic sign of a shock front passing by. On its own it's the least predictive of the four, but it's a useful confirmation signal.
Space Storm Index (SSI) (unitless)
How to read this: The Space Storm Index is a Aurora Forecast Tonight developed metric that takes into account magnetic field orientation, solar wind velocity, and solar wind density in order to estimate developing storm conditions. Conditions greater than about 40 are indicative of a developing geomagnetic storm, and larger values can indicate a more potent storm developing.