During the sinking of the airship Italia, the requests for help sent via radio by General Umberto Nobile were not intercepted by the nearby ship of the Regia Marina, anchored in the Svalbard Islands, but by a young Russian amateur radio operator 1.900 kilometers away. But what should the survivors of the mythical Red Tent have done to get their desperate SOS to the nearest emergency services?
With the study “The Shipwreck of the Airship “Dirigibile Italia” in the 1928 Polar Venture: A Retrospective Analysis of the Ionospheric and Geomagnetic Conditions” just published in Space Weather magazine, a team of researchers from the National Institute of Geophysics and Volcanology (INGV) and the Rutherford Appleton Laboratory (UK), thanks to the application of recent geophysical models, and analyzing the geomagnetic observations at the time of the shipwreck, he managed to reconstruct the polar ionosphere at the time of the tragedy and to calculate the right radio frequencies that the survivors should have used to communicate with the closest rescue services, overcoming the adverse space weather conditions that hindered normal radio communications.
Space meteorology includes many geophysical phenomena that find their origin in the interaction between the Sun and the Earth, examples are the variations of the geomagnetic field and the perturbations of the earth's ionosphere. This study highlights the role that adverse space weather conditions have played in the rescue operations of the Red Tent survivors. The description and prediction of the phenomena due to the interaction between the Sun and the Earth has required, in the decades of the last century, a continuous and systematic observation of the geophysical parameters that characterize their nature. From these observations it has been possible to obtain mathematical physical models which have been elaborated and perfected in recent years to be used also retrospectively, in order to describe past situations. It was one of these models that allowed the reconstruction of the polar ionosphere at the time of the sinking of the airship Italia, allowing to calculate the radio frequencies that the survivors would have had to use to make their SOS go through. The values obtained scientifically confirmed the intuition of the scholars of the time, namely, that the short-wave radio frequencies used by the survivors were not suitable for radio links with the rescuer ship. It should be noted, however, that in addition to the difficulties of radio propagation via the ionosphere, in the days of the downpour, disturbances generated by a geomagnetic storm were added, further complicating the situation.
The importance of scientifically analyzing and demonstrating past events is fundamental for future explorations, such as lunar explorations or interplanetary travel, to prevent similar situations from reoccurring.
#ingv #spaceweather #dirigibileitalia #tendarossa
Figure 1 - The Italia airship at NyAlesund and Gen. Umberto Nobile, courtesy of Irene Schettino Nobile.
Figure 2 - The figure shows the skip distance in green and the so-called "skip zone" in blue. The skip distance is defined as the shortest distance between a transmitter and a receiver such that radio waves (in black) of a given frequency can be received by reflection in the ionosphere. The "skip zone", also referred to as the silent zone or dead zone, is the region where a radio transmission cannot be received; it is therefore the area between the point where the propagation of radio waves on the ground ends (ground wave), blue triangle, and the closest point where the radio signal can be picked up after being reflected from the ionosphere.