Space weather, right now
Solar wind and geomagnetic data from NOAA's Space Weather Prediction Center, drawn in your browser and refreshed every five minutes.
- Solar wind speed
- —km/s
- Proton density
- —p/cm³
- IMF Bz
- —nT
- Planetary Kp
- —
Solar wind speed
Last six hours at one-minute cadence, measured at the L1 point about a million miles upstream. What you see here reaches Earth in roughly 30 to 60 minutes.
Interplanetary magnetic field, Bz
Southward (negative) lets the solar wind couple to Earth's field. This is the number that decides whether anything happens.
Kp index
Measured in three-hour periods, then forecast forward. Zero is quiet, five is a storm, nine is once a decade.
Could you see it from Las Vegas?
Working it out…
Where this comes from. Every number on this page is fetched directly from NOAA SWPC by your browser and drawn here. Nothing is stored, nothing is sent anywhere else, and there is no server of mine in the middle. Because the request goes straight from you to NOAA, NOAA sees it, the same way it would if you opened their site yourself.
Why it downloads a lot. The solar wind feeds that allow cross-origin requests come as 24-hour, one-minute files — about 250 KB compressed, 4.4 MB of JSON once unpacked. There is no shorter version, so the browser takes the whole day and keeps the last six hours of it. That is the price of not running a server in between, and it seemed like the better trade.
What it is not. This is measured solar wind and geomagnetic data, not a radiation reading and not a health measurement. The aurora line below the charts is an estimate from the Kp index, which is a rough guide to how far from the poles the auroral oval reaches, not a forecast for your street.