A spacecraft circling Mars will soon receive a Windows 98 upgrade from engineers at the European Space Agency (ESA). The Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument on board the Mars Express spacecraft has been in operation for more than 19 years and has been running Windows 98-based software. Thankfully, the ESA isn’t switching to Windows ME for the benefit of people on Earth and the Red Planet.
2018 saw the discovery of a massive subterranean liquid water reservoir on Mars thanks in large part to the MARSIS sensor aboard ESA’s Mars Express. The ESA claims that this significant new software upgrade “will enable it to look beneath the surfaces of Mars and its moon Phobos in more detail than ever before.” The organization’s first mission to the Red Planet, the Mars Express, was launched into space in 2003, and it has spent over 20 years researching the planet’s surface.

In order to look for water on Mars and learn more about its atmosphere, MARSIS uses low-frequency radio waves that reflect off the planet’s surface. The software updates will increase signal reception and onboard data processing to improve the quality of data that is relayed back to Earth. The instrument’s 130-foot antenna is capable of searching around three miles below the surface of Mars.
Carlo Nenna, a software engineer at Enginium who is assisting ESA with the upgrade, says, “We faced a number of hurdles to increase the performance of MARSIS.” Not least because Microsoft Windows 98 was used as the development environment when the MARSIS program was first created, nearly 20 years ago!
The National Institute for Astrophysics (INAF) and the ESA have used a method to store a lot of high-resolution data on the MARSIS instrument, but it quickly consumes the onboard memory. The new software enables us to turn on MARSIS for five times as long and explore a significantly larger area with each pass, according to Andrea Cicchetti, a MARSIS operation manager at INAF. “The new tools will enable us to more rapidly and thoroughly investigate these areas in high detail and determine whether they contain fresh water on Mars. Nearly 20 years after launch, it truly feels like Mars Express has a brand-new instrument.