Solar Weather
Live imagery from NASA's Solar Dynamics Observatory and real-time solar wind data from NOAA — updated every few minutes.
What does this mean for the Northern and Southern Lights?
The connection between solar weather and the aurora is direct. Solar wind — a constant stream of charged particles from the sun — arrives at Earth at hundreds of kilometers per second. When the magnetic field embedded in that wind points southward (negative Bz), it links with Earth's magnetic field and funnels particles toward the poles, igniting the aurora.
Large solar flares and coronal mass ejections (CMEs) — visible in the AIA 193 and 171 views as bright eruptions — can dramatically amplify this effect. A CME takes 1–3 days to reach Earth, so an active sun today often means strong aurora in the days ahead.
Reading the Sun: What Each View Shows
The Solar Cycle and Why It Matters
The sun follows an approximately 11-year activity cycle driven by the reversal of its magnetic poles. During solar maximum, sunspots multiply, flares erupt more frequently, and CMEs become common — all of which mean stronger and more frequent aurora displays at lower latitudes. During solar minimum, the sun is relatively calm and aurora sightings are mostly confined to polar regions.
Solar Cycle 25 began in December 2019 and has already exceeded early predictions. Higher-than-expected sunspot counts mean we are in a particularly favorable window for aurora viewing. The data panels above give you a real-time snapshot of where we are right now.
Bookmark this page and check it regularly — an active sun today is often the first signal of an aurora event 1–3 days from now. Pair this page with our free Kp alert emails and the live aurora globe to stay ahead of the next display.
Quick Reference: Solar Flare Classification
Solar flares are classified by their peak X-ray brightness. Each letter represents a 10x increase in energy output:
Understanding Solar Wind: Earth's Invisible Connection to the Sun
The solar wind is a continuous stream of charged particles — mostly protons and electrons — flowing outward from the Sun's corona in every direction. Unlike the light that reaches Earth in just eight minutes, the solar wind is a physical flow of matter traveling at hundreds of kilometers per second. It fills the entire solar system with a tenuous, magnetized plasma known as the heliosphere.
Solar wind comes in two main varieties. Slow solar wind (~300–400 km/s) streams from the quiet corona and produces gentle, steady pressure against Earth's magnetic field. Fast solar wind (~600–800 km/s) pours from coronal holes — the dark patches visible in the AIA 193 view above — and can arrive at Earth in as little as two days. When a coronal mass ejection launches directly toward Earth, the wind can exceed 1,000 km/s and dramatically compress the magnetosphere, triggering the strongest aurora storms.
Scientists measure the solar wind in real time using spacecraft positioned at the L1 Lagrange point, roughly 1.5 million kilometers sunward of Earth. NASA's DSCOVR satellite (and its predecessor ACE) sit at this gravitational sweet spot, providing a 15- to 60-minute warning before solar wind conditions arrive at Earth. The speed, density, and magnetic field readings you see on this dashboard come from those L1 measurements, giving you a near-real-time view of what is about to hit our planet's magnetic shield.
This early-warning window is why solar wind monitoring matters so much for aurora prediction. When the solar wind suddenly speeds up or its magnetic field tilts sharply southward, space weather forecasters — and aurora chasers — know that auroral activity is likely just minutes away.
The Bz Component: The Key to Aurora Prediction
Of all the numbers on this dashboard, the Bz component of the interplanetary magnetic field (IMF) is arguably the single most important for aurora prediction. The IMF is the magnetic field embedded in the solar wind, carried outward from the Sun. It has three components (Bx, By, Bz), but Bz — the north-south component — determines whether solar wind energy can efficiently enter Earth's magnetosphere.
Earth's magnetic field points northward at the equator. When the solar wind's Bz also points northward (positive), the two fields repel each other like matching magnets, and the magnetosphere remains largely sealed. But when Bz turns southward (negative), the fields can link together in a process called magnetic reconnection. Think of it like unzipping a jacket — the protective barrier opens, and solar wind particles flood in along magnetic field lines toward the poles, igniting the aurora.
The deeper the Bz drops below zero, the more energy pours into the magnetosphere. A Bz of −5 nT may produce a modest aurora visible from high latitudes. At −10 nT, a moderate geomagnetic storm is underway and the aurora can expand to mid-latitudes. At −20 nT or beyond, the gates are wide open — expect a severe storm with aurora visible far from the poles.
Crucially, Bz can change rapidly and without warning. A CME arriving with sustained southward Bz is the recipe for a spectacular aurora storm, but even during otherwise quiet conditions a sudden Bz swing can trigger substorms that light up the sky for 30 to 60 minutes. This is why experienced aurora chasers watch the Bz panel on this page as closely as the Kp index.
Coronal Holes, CMEs, and Solar Flares: What's the Difference?
These three phenomena are often confused, but they drive aurora in very different ways. Coronal holes are persistent dark regions visible in the AIA 193 imagery above. They represent areas where the Sun's magnetic field opens outward into space, allowing fast solar wind to escape. Because the Sun rotates roughly once every 27 days, a coronal hole that faces Earth today will come around again in about four weeks, creating predictable, recurring aurora enhancement that space weather forecasters call corotating interaction regions (CIRs).
Solar flares are sudden bursts of electromagnetic radiation — X-rays, UV, and radio waves — that travel at the speed of light and reach Earth in just eight minutes. While they can cause radio blackouts and GPS interference, flares by themselves do not directly drive aurora. What matters for the aurora is whether the flare is accompanied by a CME.
Coronal mass ejections (CMEs) are the real aurora powerhouses. A CME is a massive eruption of magnetized plasma — billions of tons of solar material — hurled into space at speeds ranging from 250 to over 3,000 km/s. When a CME arrives at Earth one to four days after launch, it compresses the magnetosphere and delivers a prolonged blast of southward-directed magnetic field and dense plasma. CMEs are responsible for virtually all of the strongest geomagnetic storms and the most vivid, low-latitude aurora displays.
CIRs form where fast wind from a coronal hole overtakes the slower wind ahead of it, creating a compressed, turbulent boundary. They produce moderate, multi-day geomagnetic disturbances and are a common cause of Kp 4–5 activity. While less dramatic than CME-driven storms, CIRs are more frequent and more predictable, making them a reliable source of aurora activity for high-latitude observers.
How to Read This Dashboard Like a Space Weather Forecaster
When you visit this page, start with a simple three-step check. First, look at the Bz direction. If it is southward (negative), energy is flowing into the magnetosphere right now — aurora is possible or underway. Second, check the solar wind speed. Fast wind (>500 km/s) amplifies whatever the Bz is doing. Third, glance at the flare class. An M or X class flare in the past day or two means a CME may be on its way.
A “perfect storm” scenario looks like this: Bz deeply southward (−15 nT or more), wind speed climbing above 600 km/s, and an X-class flare within the past 48 hours. When all three align, expect a major geomagnetic storm and vivid aurora at mid-latitudes. On the other hand, a “quiet” dashboard — Bz near zero or northward, slow wind around 350 km/s, and A/B class flux — means the magnetosphere is calm and aurora is confined to polar regions.
Use this page as your early-warning system, then head to the live aurora globe to see exactly where the aurora oval sits right now. If the dashboard shows storm conditions building, the globe will show the oval expanding — use the 48-hour forecast slider to plan your evening. Pair it with our free Kp alerts so you never miss the moment conditions turn favorable.