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GreenHalos
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GreenHalos field library

Aurora science,
without false precision.

Fourteen original English guides connect primary evidence to practical observing decisions. Each article remains fail-closed for search indexing until a real named author and human science reviewer are recorded.

0 of 14 guides have completed the editorial release gate.

Science review pending

What Causes the Northern Lights?

Aurora begins with energy from the Sun, but the visible light is produced much closer to home, when energetic particles excite gases high in Earth’s atmosphere. 2 primary-source records

Science review pending

Solar Flares vs Coronal Mass Ejections

A flare is chiefly a burst of electromagnetic radiation; a CME is an expulsion of plasma and magnetic field. They are related solar events, but they are not interchangeable. 3 primary-source records

Science review pending

What Is the Kp Index?

Kp compresses planetary geomagnetic disturbance into a familiar 0–9 index. It is useful context, but it is not a local sky forecast. 3 primary-source records

Science review pending

How to Read an Aurora Forecast

The most important question is not just ‘how strong?’ but ‘which horizon, which source, and which local conditions?’ 3 primary-source records

Science review pending

How Sky Conditions Affect Aurora Viewing

Space weather controls whether aurora is active; the local atmosphere and Sun control whether its light can reach your eyes against a dark enough sky. 3 primary-source records

Science review pending

Why Does the Aurora Have Different Colours?

Auroral colour records which atmospheric species were excited, at what altitude and under what particle conditions—filtered through both the eye and the camera. 2 primary-source records

Science review pending

How Far South Can Aurora Be Seen?

There is no permanent southern boundary. The oval expands and shifts with geomagnetic activity, while visibility depends on direction, darkness, cloud and local horizon. 3 primary-source records

Science review pending

How the NOAA OVATION Aurora Forecast Works

OVATION is a short-lead model of global auroral activity. It is most useful when its forecast time, source age and modelling limits stay visible. 2 primary-source records

Science review pending

What Do Solar Wind Speed and Bz Mean?

Speed describes how fast the solar wind is moving; Bz describes the north–south component of its magnetic field. Their effects depend on context and duration. 3 primary-source records

Science review pending

How to Photograph the Northern Lights

Start with a stable camera, a wide aperture and manual focus, then adapt shutter speed and ISO to how quickly the aurora is moving. 3 primary-source records

Science review pending

How Accurate Are Aurora Forecasts?

Forecast precision decreases with lead time: detailed short-range nowcasts, broader one-to-three-day activity forecasts and qualitative long-range outlooks should never look equally certain. 3 primary-source records

Science review pending

How Geomagnetic Storms Affect Technology

Geomagnetic storms can disturb technological systems, but impact depends on storm intensity, location, infrastructure and mitigation. This guide is context, not operational advice. 3 primary-source records