Observation of O 2 1.27 μm dayglow by SPICAM IR: Seasonal distribution for the first Martian year of Mars Express (original) (raw)

Maps of the O2(1Î") Emission During the Mars Pre-Aphelion Season

2008

Introduction . Ozone and water are key species for understanding the stability and evolution of Mars’ atmosphere; they are closely linked (along with CO, H, OH, and O) through photochemistry [1-6]. Measurements of ozone on Mars have been made by both ground based telescopes [7-13] and spacecraft [14-17]. Some of these measured the total column density of ozone [8, 11, 14] while others measured ozone above 20 km [9,10, 13]. These latter measurements are performed by measuring the O2(Δ) emission rates. Together, these results give insights into the vertical column profile of ozone on Mars. Photolysis of ozone by UV light from the sun produces O(P) and O2(Δ) with 90% efficiency [18]. The O2(Δ) state has a relatively long radiative lifetime (~ 1 hour) [19]. The O2(Δ) state can also be quenched by collisions with CO2. At altitudes less than 20 km, quenching dominates so the O2(Δ) emission near 1.27 μm traces the presence of ozone in the middle atmosphere of Mars. Since 1997, we have been...

First detection of ozone in the mid-infrared at Mars: implications for methane detection

Astronomy & Astrophysics

Aims. The ExoMars Trace Gas Orbiter was sent to Mars in March 2016 to search for trace gases diagnostic of active geological or biogenic processes. Methods. We report the first observation of the spectral features of Martian ozone (O3) in the mid-infrared range using the Atmospheric Chemistry Suite Mid-InfaRed (MIR) channel, a cross-dispersion spectrometer operating in solar occultation mode with the finest spectral resolution of any remote sensing mission to Mars. Results. Observations of ozone were made at high northern latitudes (>65°N) prior to the onset of the 2018 global dust storm (Ls = 163–193°). During this fast transition phase between summer and winter ozone distribution, the O3 volume mixing ratio observed is 100–200 ppbv near 20 km. These amounts are consistent with past observations made at the edge of the southern polar vortex in the ultraviolet range. The observed spectral signature of ozone at 3000–3060 cm−1 directly overlaps with the spectral range of the methan...