Atmospheric phenomena affecting the methane lifetime on Mars

2021 ◽  
Author(s):  
John Lee Grenfell ◽  
Fabian Wunderlich ◽  
Miriam Sinnhuber ◽  
Konstantin Herbst ◽  
Markus Scheucher ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Cosmic Rays ◽  
Seasonal Changes ◽  
Galactic Cosmic Rays ◽  
Solar Cosmic Rays ◽  
Secondary Importance ◽  
Air Shower ◽  
Mixing Coefficients ◽  
Atmospheric Phenomena ◽  
Chemical Rate

<p>We investigate a range of atmospheric phenomena concerning their potential to address the Martian methane lifetime discrepancy. This refers to the over-estimate of the modelled lifetimes compared to observations by a factor of up to six hundred. We apply a newly developed atmospheric photochemical model where we vary in a Monte Carlo approach the chemical rate and Eddy mixing coefficients within their current uncertainties. We also investigate the effect of air shower events due to galactic cosmic rays and solar cosmic rays. Our results suggest that the current uncertainty in chemical rates and transport together with seasonal changes in the water column can likely account for up to a factor of about thirty in the Mars methane lifetime discrepancy whereas the air shower effects are likely to be of secondary importance.</p>

scholarly journals Short- and Medium-Term Induced Ionization in the Earth Atmosphere by Galactic and Solar Cosmic Rays

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Alexander Mishev
Keyword(s):  
Cosmic Rays ◽  
Cosmic Ray ◽  
Ground Level ◽  
Galactic Cosmic Rays ◽  
Earth Atmosphere ◽  
Medium Term ◽  
Ground Level Enhancement ◽  
Solar Cosmic Rays ◽  
The Earth ◽  
Ionization Effect

The galactic cosmic rays are the main source of ionization in the troposphere of the Earth. Solar energetic particles of MeV energies cause an excess of ionization in the atmosphere, specifically over polar caps. The ionization effect during the major ground level enhancement 69 on January 20, 2005 is studied at various time scales. The estimation of ion rate is based on a recent numerical model for cosmic-ray-induced ionization. The ionization effect in the Earth atmosphere is obtained on the basis of solar proton energy spectra, reconstructed from GOES 11 measurements and subsequent full Monte Carlo simulation of cosmic-ray-induced atmospheric cascade. The evolution of atmospheric cascade is performed with CORSIKA 6.990 code using FLUKA 2011 and QGSJET II hadron interaction models. The atmospheric ion rate is explicitly obtained for various latitudes, namely, 40°N, 60°N and 80°N. The time evolution of obtained ion rates is presented. The short- and medium-term ionization effect is compared with the average effect due to galactic cosmic rays. It is demonstrated that ionization effect is significant only in subpolar and polar atmosphere during the major ground level enhancement of January 20, 2005. It is negative in troposphere at midlatitude, because of the accompanying Forbush effect.

The Drugs and Natural Antioxidants as the Components of Anti-radiation Countermeasures during Cosmic Flights

2017 ◽  
pp. 66-73 ◽  
Author(s):  
И. Ушаков ◽  
I. Ushakov ◽  
М. Васин ◽  
M. Vasin
Keyword(s):  
Solar Activity ◽  
Cosmic Rays ◽  
Radiation Effects ◽  
High Energy ◽  
Galactic Cosmic Rays ◽  
Stress Factors ◽  
Solar Cosmic Rays ◽  
Post Radiation ◽  
The Impact

Radiation situation for cosmonauts over long-term cosmic flights is caused by low-rate radiation of galactic cosmic rays and solar cosmic rays consisting of high-energy proton as well as heavy particles (Z>10) within 1-2 % that is exclusively a threat of stochastic radiation effects (small increase of cancer risk and decrease of mean life span) for men. During interplanetary expedition periods the small probability of raised solar activity there is a threat of exposure to astronauts at doses that cause deterministic radiation effects leading to the development of the disease as a clinical manifestation of radiation injuries,. In a similar scenario it is necessary to have available to cosmic ship anti-radiation countermeasures for cosmonaut protection. Among radioprotective equipment can be provided with radiation protective agents and partial shielding of body separate section providing the best condition for post-radiation repair of radiosensitive body tissues. Preparation B-190 (indralin) is the most perspective from a small numbers of other radioprotectors permitting for men administration. Besides high radioprotective efficacy and large broadness of protective action B-190 is well tolerated including the impact of extrem flight factors. Antiemetic agent latran (ondansetron) is most interesting among preparation for prophylaxis and reduction of prodromal radiation reaction. To accelerate post-radiation hematopoietic recovery after raised solar activity an administration of radiomitigators (riboxin et al.) is substantiated. Neupomax (neupogen) is recommended as a preparation for pathogenesis therapy of acute radiation syndrome. Possible consequences of long-term cosmic voyages for oxidative stress development are taken into consideration. On their basis of nNatural antioxidants, preparations and nutrients radiomodulators, fully qualitative nutrition including vegetable food enriched flavonoids, vitamins C, E and carotene potentially prevent a shorten of cosmonaut biological age induced by solar cosmic rays and galactic cosmic rays and stress factors of long-term cosmic voyages. Radiomodulators are low and non-toxic and have not side effects in recommended doses. Their radioprotective effect is directly induced by adaption reaction on cellular and organismic levels through gene expression modulation and in that way the increase of non-specific body tolerance. The implementation of radiomodulator action is possible through hormesis mechanism.

Protons of radiation belts as a source of hydrogen in the Earth’s atmosphere

2019 ◽  
Vol 489 (5) ◽  
pp. 502-505
Author(s):  
V. B. Lapshin ◽  
M. S. Ivanov ◽  
N. G. Kotonaeva ◽  
V. A. Burov ◽  
A. Yu. Repin
Keyword(s):  
Solar Wind ◽  
Cosmic Rays ◽  
Atomic Hydrogen ◽  
Outer Space ◽  
Galactic Cosmic Rays ◽  
Radiation Belts ◽  
Hydrogen Ions ◽  
Solar Cosmic Rays ◽  
Order Of Magnitude ◽  
Cosmic Origin

A scenario is proposed for replenishing the Earths exosphere with atomic hydrogen of cosmic origin. An assessment was made and the coincidence of the total atomic hydrogen content in the exosphere with the number of protons (after thermolization converted into hydrogen ions) precipitated in the SAA zone during the year according to the data of the Meteor M and NOAA‑19 satellites was confirmed. The observed coincidence indicates that the rates of replenishment of hydrogen due to precipitation from radiation belts and dissipation into outer space coincide in order of magnitude. It is concluded that the exosphere hydrogen is mainly of cosmic origin and its main source is the thermalized protons of galactic cosmic rays, solar cosmic rays and partially solar wind.

scholarly journals Simulating a Measurement of the 2nd Knee in the Cosmic Ray Spectrum with an Atmospheric Fluorescence Telescope Tower Array

2014 ◽  
Vol 2014 ◽  
pp. 1-6
Author(s):  
Jiali Liu ◽  
Qunyu Yang ◽  
Yunxiang Bai ◽  
Zhen Cao
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Cosmic Rays ◽  
Event Rate ◽  
Cosmic Ray ◽  
Detector Response ◽  
Simulation Tool ◽  
Trigger System ◽  
Air Shower ◽  
Light Generation

A fluorescence telescope tower array has been designed to measure cosmic rays in the energy range of 1017–1018 eV. A full Monte Carlo simulation, including air shower production, light generation and propagation, detector response, electronics, and trigger system, has been developed for that purpose. Using such a simulation tool, the detector configuration, which includes one main tower array and two side-trigger arrays, 24 telescopes in total, has been optimized. The aperture and the event rate have been estimated. Furthermore, the performance of theXmax⁡technique in measuring composition has also been studied.

A Study of the Shadowing of Galactic Cosmic Rays by the Sun in a Quiet Phase of Solar Activity with the Tibet Air Shower Array

2000 ◽  
Vol 541 (2) ◽  
pp. 1051-1058 ◽  
Author(s):  
M. Amenomori ◽  
S. Ayabe ◽  
Caidong ◽  
Danzengluobu ◽  
L. K. Ding ◽  
...  
Keyword(s):  
Solar Activity ◽  
Cosmic Rays ◽  
Galactic Cosmic Rays ◽  
The Sun ◽  
Air Shower ◽  
Shower Array ◽  
Air Shower Array

scholarly journals Fine and Hyperfine Structure in the Spectrum of Secular Variations of Atmospheric 14C

Radiocarbon ◽  
1989 ◽  
Vol 31 (03) ◽  
pp. 704-718 ◽  
Author(s):  
Paul E Damon ◽  
Songlin Cheng ◽  
Timothy W Linick
Keyword(s):  
Cosmic Rays ◽  
Hyperfine Structure ◽  
Ice Cores ◽  
Cosmic Ray ◽  
Galactic Cosmic Rays ◽  
Solar Cosmic Rays ◽  
Secular Variations ◽  
Galactic Cosmic Ray ◽  
Long Term Trend

The coarse structure of the 14C spectrum consists of a secular trend curve that may be closely fit by a sinusoidal curve with period ca 11,000 yr and half amplitude ±51. This long-term trend is the result of changes in the earth's geomagnetic dipole moment. Consequently, it modulates solar components of the 14C spectrum but does not appear to modulate a component of the spectrum of ca 2300-yr period. The ca 2300-yr period is of uncertain origin but may be due to changes in climate because it also appears in the δ18O spectrum of ice cores. This component strongly modulates the well-known ca 200-yr period of the spectrum's fine structure. The hyperfine structure consists of two components that fluctuate with the 11-yr solar cycle. One component results from solar-wind modulation of the galactic cosmic rays and has a half-amplitude of ca ±1.5. The other component is the result of 14C production by solar cosmic rays that arrive more randomly but rise and fall with the 11-yr cycle and appear to dominate the fluctuation of the galactic cosmic-ray-produced component by a factor of two.

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