Leonardo's technologies in space on board the EarthCARE mission

29 May 2024

Better understanding the relationship between clouds, aerosols, and radiation and their combined effects on the Earth and climate systems. This is the aim of EarthCARE, a mission by the European Space Agency (ESA) and the Japanese Space Agency (JAXA), whose launch took place from Vandenberg Air Force Base (California) at 00:20 CEST (28 May, 15:20 local time) on 29 May. Leonardo provided its technological contribution to the mission, also thanks to the support of the Italian Space Agency (ASI).

What are the interactions between aerosols and clouds? How much solar and earth surface radiation are reflected or absorbed by these phenomena? These are some of the questions that will be answered thanks to EarthCARE, which will contribute to the knowledge of radiative transfer in the atmosphere and will allow us to understand how these natural elements influence the planet's delicate temperature balance. For the first time, the mission will be able to provide vertical profiles of clouds and aerosols from space, on a planetary scale, helping to improve the accuracy of climate models.

In this context, Leonardo has developed some of the technologies that will go into orbit on board the ESA mission. An example is the laser transmitter for the ATLID instrument, built in the Pomezia (RM) and Campi Bisenzio (FI) sites, which will help collect data on aerosol and cloud particles. The laser is composed of approximately eighty optical elements, designed to remain perfectly aligned even during the extreme environmental conditions, such as vibrations during launch, absence of gravity and low temperatures in orbit. From space, it can observe tiny particles in the atmosphere, which are less than a thousandth of a millimeter in size or thirty times smaller than the thickness of a hair. To achieve this, the transmitter emits about 3,000 very short ultraviolet pulses per minute. These are “reflected” by aerosols (such as thin solid particles, liquid droplets suspended in the air or other gas) or from thin clouds, to generate a return signal containing information on the distance and type of particles observed and subsequently analysed by the receiver of the ATLID instrument.

The photovoltaic panels (PVA) for EarthCARE are manufactured in the Nerviano (MI) site. They are made with a special white paint to resist the erosive phenomena typical of the mission's orbit (around 390 km). The satellite has a single 11-metre wing, with five panels over 5,500 cells, capable of delivering up to 5kW, equal to the needs of two small apartments.

In Campi Bisenzio, a sensor was built, which is activated only when necessary and uses the Sun as a reference to orient the satellite.

JAXA's "Cloud Profiling Radar (CPR)" instrument also has Leonardo technology. In fact, the transmitter ("High Power Transmitter" - HPT) was created in the Nerviano site. It amplifies and supplies the instrument's antenna with the power and signal to operate the radar.

In the UK, Thales Alenia Space built the Broad-Band Radiometer (BBR), which consists of three telescopes, sophisticated calibration systems and detectors. This device will measure both the reflected solar flux and the terrestrial heat flux through a spectrum from ultraviolet to infrared.