To study the formation of the northern lights and the behavior of plasma waves in the ionosphere, researchers created miniature northern lights in the sky over Alaska. Phenomenon visible up to 500 kilometers away.
You will also be interested in this
(on video) The Northern and Southern Lights: How are they formed? Thanks to Adrien Mauduit, let’s indulge ourselves in the contemplation of these spectacular polar auroras that …
Alaskans were able to witness an unusual phenomenon last week in the form of a small, very localized Aurora Borealis. This is a series of experiments conducted by several American universities using the radio transmitters of the Harp Observatory (High Frequency Active Auroral Research Program,
HARP was built to study the highest layers of the atmosphere, namely the thermosphere and ionosphere. The observatory uses a phased antenna array, composed of 180 antennas spread over 12 to 16 hectares, with a maximum power of 3.6 megawatts. From 4 to 8 November, a number of experiments were conducted to create artificial luminescence to study the northern lights. The researchers emitted a series of radio waves at various frequencies between 2.8 and 10 megahertz.
Red and green spots visible up to 500 kilometers away
The pulses last for 30 seconds, during which they send energy to the gases located in the atmosphere, creating an ionization process. During the next 30 seconds, when the transmission is cut off, the electrons recombine with molecules and atoms, producing a glow visible at an altitude of between 200 and 250 km. According to Harp, the event should be visible to people up to 500 kilometers away from the observatory, and should look like a bright red or green spot.
Despite the extremely limited scope of the phenomenon, some conspiracy theorists on social networks did not hesitate to make the connection with the Northern Lights seen in France last week, although they are of natural origin.
This is not the first time that Harp has created an artificial Aurora Borealis, as the first experiment of its kind took place in 2005. In addition to studying the mechanisms behind the aurora borealis, researchers hope to discover whether some of the waves are plasma waves amplifying other very low-frequency waves, and whether these plasma waves can be used by satellites to detect collisions and Can be done to avoid them.