Named after the “divine keeper of the winds” in Greek mythology, Aeolus is the European Space Agency’s (ESA) satellite mission for studying the Earth’s winds on a global scale. Not only does it provide the necessary data to improve weather forecasting accuracy, but it also contributes to long-term climate research.
Launched in August 2018, Aeolus is the first satellite capable of performing global wind observation in near real time, with its various technologies able to analyse Earth’s winds to understand how their elements, including pressure, temperature and humidity, are interconnected.
Aeolus never ceases to amaze thanks to its revolutionary instrument called ALADIN (Atmospheric LAser Doppler INstrument), the LIDAR equipped with the most powerful ultraviolet (UV) laser transmitter ever built for a spatial application that was made by Leonardo with the support of the Italian Space Agency.
ALADIN is composed of three parts – a powerful laser, a telescope and a highly sensitive receiver. The UV laser transmitter – developed and manufactured in Leonardo’s plants in Pomezia (Rome) and Campi Bisenzio (Florence) – emits short and powerful pulses of UV light towards the atmosphere, which is then reflected by the molecules and particles that move under the action of the wind at different altitudes. By measuring the wavelength of the return laser light, the instrument can calculate information relating to the wind speed. It is a totally innovative approach in measuring the wind from the space.
"It is a great achievement,” says Alberto Cosentino, Head of the Space Laser Systems at Leonardo. “Thanks to the ALADIN laser transmitter, the satellite data has helped make weather forecasting more accurate.”
In fact, Aeolus has provided important data during the Covid-19 emergency. With lockdown measures in force around the world, there has been a drastic drop in commercial flights, with repercussions not only on international travel, but also on aspects relating to weather forecasting. Some planes are equipped with special sensors and usually transmit atmospheric data to Earth. These data are fundamental to meteorological studies. However, with planes grounded, Aeolus has fulfilled a critical task by providing some of the missing data. As early as January 2020, the UK-based European Center for Medium-Range Weather Forecasts, began using wind information coming from the satellite, with great results.
But the biggest success came recently when ESA decided to make public the data collected by Aeolus. “This step means that the satellite and the transmitter not only work well, but above all, that the collected measurements of the wind speed are reliable. This is truly a great success” adds Cosentino.
Thanks to a more complete and in-depth analysis of the Earth’s winds, we can soon improve studies on climate change, global warming and air pollution.
The day is approaching when, thanks to Aeolus, we can get absolutely reliable weather forecasts on our mobile phones, with seven-day reliability rather than the current two.
