Space Weather

A sinister-looking aurora over Iceland
(Photo by D. Necchi).

Interested to see and photograph the aurora? Regional Auroral Forecasts will help you.

Auroras are a beautiful and harmless manifestation of space weather processes. Eruptions on the solar surface can occasionally cause rapid variations in the near-Earth space environment, which are associated with bright auroras appearing at high latitudes and in extreme cases also at middle and low latitudes. Large-scale solar events, such as coronal holes, flares and coronal mass ejections are responsible for the most intense geomagnetic disturbances in the Earth's space environment. Deflections in the geomagnetic field are caused by changing electric currents in the upper atmosphere, which then result in beautiful auroral displays. The Regional Auroral Forecast service (RAF) follows continuously solar activity and variations in the geomagnetic field and can help you decide when it is a good time to put on something warm and go outside to a place with a nice view towards the Northern horizon.

How is auroral light generated ?

Auroral light is generated in the upper parts of our atmosphere with a similar mechanism as the illumination by neon lights: in dilute gas, electrons collide with heavier atoms or molecules and as a consequence the atoms are excited. When the atoms return from the excited state back to their normal state the extra energy is released as light. In the hunt for auroras it is important to be patient and wait until your eyes get adjusted to the darkness. It is good to know that the human eye observes auroras in a different way to cameras. Our eyes see dim auroras as white or grey structures, while cameras with long enough exposure times show the same auroras as green, red or purple. With bright auroras this problem does not exist. Instead the challenge is to be in the correct place at the correct moment. Unfortunately the most beautiful sightings are often quite short-lived, so instead of going in to wake up your friends, be selfish and enjoy the show.

This service is implemented through a combination of products, tools and alerts which can be found through the following tabs along with expert support provided by the teams constituting the SWE Network. Should you require further guidance in the use of this service, or have specific questions about any aspects of the service presented here, don’t hesitate to contact the Helpdesk.

This service page is curated by the ESC Geomagnetic Conditions. For further information, please contact SSCC Helpdesk. 

The most beautiful manifestation of space weather is the aurora. Several products available here are tailored for the auroral tourism sector and these are grouped under Auroral Visible Imaging:

• The Aurora forecast service (Regional Aurora Forecast, RAF) by the Finnish Meteorological Institute (FMI). This product shows a map with the estimated location of the auroral oval and, as supporting information cloudiness predictions. The product also contains features such as a set of three “lamps” which turn to red in the cases where the National Oceanic and Atmospheric Administration (NOAA) has issued alerts of enhanced Kp values or on solar flares during the recent 2-3 days.
• Auroral images (Scotland) by the British Geological Survey (BGS). The product provides auroral images for northern UK (Lerwick observatory) taken with basic lens - 2.9mm focal length, f1.6, ~100 degree FOV (BGS AuroraCam)
• The Auroral data from Kiruna by the Swedish Institute of Space Physics (IRF), containing optical auroral data for northern Sweden during the winter season
• Aurora nowcast for Greenland by the Technical University of Denmark (DTU). The product contains a map that show the latest estimated position of the polar ionospheric electrojet, and thus the auroral oval in the north.

To assess the Earth atmosphere and geomagnetic environment in more detail, the service includes products containing local external magnetic field on ground and local geomagnetic induced geoelectric field.

The products for interplanetary medium at L1 give forecasts and real-time data for solar wind properties.

No alert is associated with this service

This section provides links to web pages or resources that are not part of the ESA Space Weather Service Network or esa.int domain. These sites are not under ESA control, and therefore ESA is not responsible for any of the information or links that you may find there.  

Reference documents

• Northern Lights
• Auroras in Finland
• Forecasting auroras from regional and global magnetic field measurements. Kauristie et al. (2016), Geosci. Instrum. Method. Data Syst., 5, 253-262.
• Two methods to forecast auroral displays. Sigernes et al. (2011), J. Space Weather Space Clim., 1, A03.