The Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument onboard ESA’s Mars Express spacecraft is receiving a major software upgrade that will allow it to see beneath the surfaces of Mars and its moon Phobos in more detail than ever before.
An artist’s impression of ESA’s Mars Express spacecraft. Image credit: ESA / ATG Medialab / DLR / FU Berlin / CC BY-SA 3.0 IGO.
“After decades of fruitful science and having gained a good understanding of Mars, we wanted to push the instrument’s performance beyond some of the limitations required back when the mission began,” said MARSIS deputy principal investigator Dr. Andrea Cicchetti, an operation manager at INAF.
“We faced a number of challenges to improve the performance of MARSIS,” added Dr. Carlo Nenna, MARSIS on-board software engineer at Enginium.
“Not least because the MARSIS software was originally designed over 20 years ago, using a development environment based on Microsoft Windows 98.”
MARSIS was crucial in the search for and discovery of signs of liquid water on Mars, including a suspected lake of salty water buried under 1.5 km of ice in the southern polar region.
The instrument’s 40-m-long antenna sends low frequency radio waves towards the planet, which are reflected from any surface or subsurface boundary they encounter.
For most, this will be the surface of Mars, but a significant fraction travels through the crust to be reflected at sub-surface interfaces between layers of different material, including ice, soil and rock.
By examining the reflected signals, planetary scientists can map the structure below the Martian surface to a depth of a few kilometers and study properties such as the thickness and composition of its polar ice caps and the properties of volcanic and sedimentary rock layers.
“Previously, to study the most important features on Mars, and to study its moon Phobos at all, we relied on a complex technique that stored a lot of high-resolution data and filled up the instrument’s on-board memory very quickly,” Dr. Cicchetti said.
“By discarding data that we don’t need, the new software allows us to switch MARSIS on for five times as long and explore a much larger area with each pass.”
“There are many regions near the south pole on Mars in which we may have already seen signals indicating liquid water in lower-resolution data,” said Mars Express scientist Dr. Colin Wilson, of ESA.
“The new software will help us more quickly and extensively study these regions in high resolution and confirm whether they are home to new sources of water on Mars.”
“It really is like having a brand new instrument on board Mars Express almost 20 years after launch.”
