ESA engineers are preparing for a Windows 98 upgrade to an orbiter currently circling Mars. Mars Express has been in operation for over 19 years.

The Mars Advanced Radar for Subsurface and Ionospheric Sounding instrument (MARSIS) has been running on software developed using Windows 98.

The ESA has decided not to upgrade its systems to Windows ME, which is good for humanity and the Red Planet.

ESA's Mars Express used the MARSIS instrument to discover a large underground aquifer of liquid water in 2018.

According to the ESA, this major software update "will allow it to see beneath the surface of Mars and its moon Phobos with more detail than ever before."

Mars Express was launched into space by the agency in 2003. It has been exploring Mars' surface for nearly two decades.

MARSIS uses radio waves at low frequencies to bounce off Mars' surface to find water and study its atmosphere. The 130-foot antenna can search three miles below Mars' surface.

In addition, software upgrades will improve signal reception and onboard processing to increase the quality of data sent back to Earth.

Carlo Nenna is a software engineer at Enginium and helped ESA with the upgrade. "Not least, because the MARSIS program was originally developed over 20 years ago using a Microsoft Windows 98 development environment!"

ESA operators and the National Institute for Astrophysics (INAF) have used a technique to store many high-resolution data on MARSIS.

However, it takes up a lot of onboard memory. Andrea Cicchetti is a MARSIS operations manager at INAF.

"By discarding data we don't use, the new software allows me to switch MARSIS off five times longer and explore a larger area with every pass."

"The new software will allow us to more quickly and thoroughly study these regions in high-resolution and confirm whether there are new water sources on Mars.

It's almost like having a new instrument aboard Mars Express nearly 20 years after its launch.