The Mars Atmosphere Dynamics aNd chEmistry Submillimeter Spectrometer, MADNESS, selected for the ESA LightShip-1 mission to Mars

The Mars Atmosphere Dynamics aNd chEmistry Submillimeter Spectrometer (MADNESS) was selected by ESA for the LightShip-1 mission to address the key science goals of i) Atmospheric circulation and dynamics, ii) Water cycle, clouds and chemistry, and iii) Enabling Mars exploration. Inherited from the flight-proven Submillimetre Wave Instrument (SWI) instrument currently operating aboard the Juice mission to Jupiter, MADNESS will provide repeatable, high-precision measurements of the Martian atmospheric dynamics, thermal structure, and chemical composition from 20 to 120 km altitude, along with monitoring of surface thermal emission.

MADNESS features two spectral channels, covering the 527-635 GHz and 1066-1286 GHz ranges, each equipped with dual spectrometers:

• A broadband autocorrelator spectrometer (ACS) for sounding of multiple species simultaneously,
• A Chirp Transform Spectrometers (CTS) for ultra-high-resolution line profiling.

Using dedicated pointing mechanisms that enable both nadir and limb observations, and targeting key gaseous species (CO, H₂O, H₂O₂, HO₂, O₂, HCl, HF, NO, and their isotopologues), MADNESS will enable unprecedented insights into Mars' circulation, water cycle, and active hydrogen, oxygen, chlorine, and nitrogen chemistry.

Leveraging the Doppler shift of spectral lines, MADNESS will directly and comprehensively survey, for the first time, horizontal wind velocities from 20 to 120 km altitude, with a precision and vertical resolution better than 10 m/s & 10 km. It will simultaneously probe the temperature structure over the same vertical range, with 1 K accuracy. Unaffected by dust opacity and non-local thermodynamical equilibrium (non-LTE) effects, MADNESS will provide the most detailed and seasonally complete climatology of Mars to date. These first-ever co-located measurements of temperature and wind represent an unprecedented dataset for Mars, enabling direct constraints on atmospheric dynamics and facilitating data assimilation into global circulation models to improve predictive understanding of the Martian climate.

MADNESS will also conduct a comprehensive investigation of the Martian water cycle and its associated oxidizing chemistry, through precise vertical profiling of key species. Combined with transport effects derived from wind measurements, these observations will offer critical insights into atmospheric stability and photochemical balance, shedding light on the long-term evolution of Mars' atmosphere.

MADNESS draws on advanced heterodyne receiver designs and compact, low-resource subsystems tailored to Lightship’s mass, power, and data constraints. With strong heritage in submillimeter planetary spectroscopy, our team combines scientific excellence with proven technical capabilities. Spread over seven European countries and Japan, the MADNESS scientific team gathers experts in spacecraft operation planning, submillimeter data analysis, Mars atmospheric dynamics and chemistry, Mars data assimilation, and surface physics, providing a uniquely integrated view of Mars' atmospheric circulation, water cycle, and photochemistry, taking a step beyond our current understanding of the Red Planet and paving the way for future exploration.