Riometer radio antennae at night with an aurora in the night sky,Poker Flat Research Range (PFRR),Alaska,USA. A riometer is used in polar regions to study aurorae,solar-induced electromagnetic storms of the polar ionosphere. The ionosphere is a region of the upper atmosphere that lies 50-600 kilometres above Earth's surface. This riometer is a 16x16 array of 256 radio antennae. Riometer stands for Relative Ionospheric Opacity Meter using Extra-Terrestrial Electromagnetic Radiation. As the coloured light displays of the aurorae block the passage of radio waves from space to the Earth,they show up as shadows on the riometer display. PFRR is part of the University of Alaska | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Sirulnikoff, Alan |
Taille de l’image : | 4535 px × 3127 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |