Mars atmospheric losses induced by the solar wind: Comparison of observations with models

Вайсберг, О. Л.

doi:10.1016/j.pss.2015.09.007

Cited by 10 publications

(2 citation statements)

References 73 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several observations on Mars, such as characteristic surface morphologies like large fluid-eroded channels, dendritic networks, fluvial valleys, and glacial features [1], and the formation of water-depending minerals like hematite [2], indicate that the planet had a warmer (even though mostly freezing [3]), wetter and more habitable climate in its early history [4]. However, the loss of its magnetic field enabled the solar wind to sputter away large parts of the Martian atmosphere which caused a climate change leading to the dry, cold, and hostile planet that we know today [5,6]. Hence, putative Martian microorganisms would have had to adapt to a gradual decrease in the availability of liquid water.…”

Section: Introductionmentioning

confidence: 99%

A New Record for Microbial Perchlorate Tolerance: Fungal Growth in NaClO4 Brines and its Implications for Putative Life on Mars

Heinz

Krahn

Schulze‐Makuch

2020

Life

View full text Add to dashboard Cite

The habitability of Mars is strongly dependent on the availability of liquid water, which is essential for life as we know it. One of the few places where liquid water might be found on Mars is in liquid perchlorate brines that could form via deliquescence. As these concentrated perchlorate salt solutions do not occur on Earth as natural environments, it is necessary to investigate in lab experiments the potential of these brines to serve as a microbial habitat. Here, we report on the sodium perchlorate (NaClO4) tolerances for the halotolerant yeast Debaryomyces hansenii and the filamentous fungus Purpureocillium lilacinum. Microbial growth was determined visually, microscopically and via counting colony forming units (CFU). With the observed growth of D. hansenii in liquid growth medium containing 2.4 M NaClO4, we found by far the highest microbial perchlorate tolerance reported to date, more than twice as high as the record reported prior (for the bacterium Planococcus halocryophilus). It is plausible to assume that putative Martian microbes could adapt to even higher perchlorate concentrations due to their long exposure to these environments occurring naturally on Mars, which also increases the likelihood of microbial life thriving in the Martian brines.

show abstract

Section: Introductionmentioning

confidence: 99%

A New Record for Microbial Perchlorate Tolerance: Fungal Growth in NaClO4 Brines and its Implications for Putative Life on Mars

Heinz

Krahn

Schulze‐Makuch

2020

Life

View full text Add to dashboard Cite

show abstract

“…As a planet without a strong magnetic field of internal origin, but with a thin tenuous atmosphere, Mars interaction with the solar wind typically follows that of an unmagnetized atmospheric obstacle to the solar wind (Nagy et al, 2004;Vaisberg, 2015). As such the solar wind magnetic field and plasma passing over the Martian obstacle forms an induced magnetosphere through mass loading of the solar wind magnetic field with planetary plasma and the induction of currents and magnetic fields in the Martian ionosphere.…”

Section: Introductionmentioning

confidence: 99%

MAVEN Case Studies of Plasma Dynamics in Low‐Altitude Crustal Magnetic Field at Mars 1: Dayside Ion Spikes Associated With Radial Crustal Magnetic Fields

et al. 2019

View full text Add to dashboard Cite

We report for the first time, simultaneous ion, electron, magnetic field vector and electric field wave measurements made possible by Mars Atmosphere and Volatile EvolutioN, during ion energy flux spikes in low‐altitude radial crustal magnetic fields on the Mars dayside. Observations show energetic electrons and ions (E > 25 eV) precipitating on magnetic field lines assumed as closed. Ions (E < 1.4 keV) display broad velocity distributions toward Mars, showing ions flowing from higher altitude possibly after magnetic reconnection or loss cone filling from pitch angle scattering effects. Precipitating ions (E < 1.4 keV) show nonadiabatic features depending on ion mass and energy and returning ions (E < 1.4 keV) show evidence of conserving the first adiabatic invariant in a mirror field. We observe magnetic field perturbations up to 60 nT, electric field wave amplitudes up to 38 mV/m, and brief periods of peaked electron spectra. At ∼175 km and at times Mars Atmosphere and Volatile EvolutioN is below the mirroring altitude of electrons, we observe mirroring and transverse heating of H+ ions alongside increased electric field wave amplitude fluctuations. It suggests field aligned potential drops result from different mirror altitudes of ions and electrons. Ions E > 1.4 keV (O+) occur as injected accelerated ion beams and ions heated after energization or deceleration. Energy dispersed kilo‐electron‐volt ions suggest a selection effect in radial magnetic fields for lower‐energy Marsward ions, compared to reflection of higher‐energy anti‐Sunward ions. Precipitating kilo‐electron‐volt ions show energy deposition rates of 3.6 ×10−6 W/m2 and sputtering escape rates from precipitating O+ ions of 1.5 ×105/(cm2.s) and 2.1 ×106/(cm2.s) are calculated.

show abstract

Special issue editorial – Plasma interactions with Solar System Objects: Anticipating Rosetta, Maven and Mars Orbiter Mission

Coates

Wellbrock

Yamauchi

2015

Planetary and Space Science

View full text Add to dashboard Cite

Within our solar system, the planets, moons, comets and asteroids all have plasma interactions. The interaction depends on the nature of the object, particularly the presence of an atmosphere and a magnetic field. Even the size of the object matters through the finite gyroradius effect and the scale height of cold ions of exospheric origin. It also depends on the upstream conditions, including position within the solar wind or the presence within a planetary magnetosphere. Soon after ESA's Rosetta reached comet Churyumov-Gerasimenko, NASA's Maven and ISRO's Mars Orbiter Mission (MOM) reached Mars, and ESA's Venus Express mission was completed, this issue explores our understanding of plasma interactions with comets, Mars, Venus, and moons in the solar system. We explore the processes which characterise the interactions, such as ion pickup and field draping, and their effects such as plasma escape. Papers are based on data from current and recent space missions, modelling and theory, as we explore our local part of the 'plasma universe'.

show abstract

Mars atmospheric losses induced by the solar wind: Comparison of observations with models

Cited by 10 publications

References 73 publications

A New Record for Microbial Perchlorate Tolerance: Fungal Growth in NaClO4 Brines and its Implications for Putative Life on Mars

A New Record for Microbial Perchlorate Tolerance: Fungal Growth in NaClO4 Brines and its Implications for Putative Life on Mars

MAVEN Case Studies of Plasma Dynamics in Low‐Altitude Crustal Magnetic Field at Mars 1: Dayside Ion Spikes Associated With Radial Crustal Magnetic Fields

Special issue editorial – Plasma interactions with Solar System Objects: Anticipating Rosetta, Maven and Mars Orbiter Mission

Contact Info

Product

Resources

About