The mystery of radio echo

  In 1962, the radio signals emitted by the Jacamalca Radio Astronomy Observatory near Lima, the capital of Peru, were reflected by an object, and the ground receiver received some strange echo signals that were difficult to explain. The source of these mysterious echoes appeared at an altitude of 130 kilometers to 160 kilometers above sea level. What could reflect radio waves in such a high sky?
Unique radar echo

  In order to understand what is happening in such a high atmosphere, the researchers launched rockets equipped with antennas and particle detectors into the high-altitude area. These devices on the rocket can detect radar waves well. But even with the use of these equipment, the researchers found nothing in the designated area, and no abnormalities were detected.
  Even more bizarre is that the strange echo phenomenon only appears during the day, and the strange echo disappears at night. Every day at dawn, the echo will appear, and the source is still located at an altitude of about 160 kilometers above the ground in the early morning. As time changes, the position of the source will gradually drop, and it has dropped to a position about 130 kilometers above the ground at noon, when the echo energy is the strongest. After noon, the source of the echo will rise again, gradually returning to a height of 160 kilometers over time. Drawing this information into an image will reveal that the path of the echo appears in the shape of a necklace.
  In 2011, the National Atmospheric Laboratory of India observed a partial solar eclipse. During the partial solar eclipse, the mysterious radio echo was suddenly silent. Later, scientists observed mysterious echoes during a solar flare, and found that the echoes went crazy, with frequent turbulence, and the echoes were very strong during this period.
Sun palm has control

  Oppenheim and Deventer from the Space Physics Center of Boston University in the United States used supercomputers to simulate strange radar echoes and found the culprit of this mysterious phenomenon-the sun.
  It all seems to be because the ultraviolet radiation emitted by the sun hits the ionosphere of the atmosphere. Solar ultraviolet radiation comes to the ionosphere in the form of photons. After hitting the ionosphere, it strips off the electrons in atmospheric molecules, and finally leaves charged ions and free electrons, which disturb the ionosphere. The weird radio echoes that people detect are radiation waves caused by ultraviolet radiation disturbing the ionosphere.
  The mystery of the mysterious radio echo was finally solved after more than 50 years. As for why the rocket launched before did not find the source of the strange echo, the scientist explained that it may be because there are too many electromagnetic waves in nature, and they are so messy that they can’t be seen.
  In fact, the rocket detection data is roughly the same as the scientists’ computer simulation data. There are no particularly strong relevant radio waves, only many ripples with very short wavelengths. Moreover, the warm atmosphere below the ionosphere is full of various noisy radio waves. The radio waves that really work are like tiny bubbles on the surface of a rough sea, so inconspicuous.