A complete loop of the aurora borealis,the Northern Lights,is seen in this extraordinary picture recorded from space by the Explorer 1 satellite. The auroral loop is seen at left,encircling the north pole. Auroras are luminous displays that occur in the night sky at high latitudes; they form rays,bands,arcs,streamers & curtains,often coloured red or green. They are caused by subatomic particles from the Sun interacting with atoms & molecules in Earth's upper atmosphere (above about 100 km). The reason that they appear at high latitudes is that the particles from the Sun are concentrated over the poles by Earth's magnetic field | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / NASA |
Taille de l’image : | 4463 px × 4400 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |