As part of the European Space Agency's Mars Express mission, the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument is soon to receive a software update, which will remove its previous operating system of Windows 98.

Nearly two decades after Mars Express launched, the software update is set to breathe new life into the orbiter that discovered water under the Martian south pole.

Even if the illusion was just a mirage, the Mars orbiter is one of the most successful projects from the ESA and has allowed us to study Mars's past and present like never before. As a result of the upgrade, MARSIS will be able to see beneath the surface of Mars and its moon, Phobos, in unprecedented detail.

“Since we have gained a better understanding of Mars through decades of research, we wanted to push the instrument's performance beyond some of the limitations set when the mission started,' Andrea Cicchetti, MARSIS Deputy Principal Investigator and Operation Manager at INAF, said in a press release.

Through the orbiter's low-frequency radio waves, scientists can map the surface and structures beneath the red planet to a depth of a few kilometers. It is expected that the update will improve signal reception and data processing on the orbiter. 

To study the most important features on Mars, and its moon Phobos, we previously used a complex technique that stored a lot of high-resolution data and consumed the instrument's memory very fast,' Cicchetti said.

As the new software discards data we don't need, MARSIS can be switched on for five times as long, which allows us to cover a much broader area with each pass.

During its mission, the orbiter will map the subsurface of Mars and look for signs of water.

'The new software will allow us to study these regions at higher resolution and confirm whether they contain new sources of water on Mars,' said ESA Mars Express scientist Colin Wilson. 

Nearly 20 years after Mars Express' launch, it is like carrying an entirely new instrument.