Radiation Analysis for Moon and Mars Missions
Issue:
Volume 8, Issue 3, September 2020
Pages:
16-26
Received:
11 October 2020
Accepted:
28 October 2020
Published:
4 November 2020
Abstract: This paper provides an overview of the radiation aspects of manned space flight to Moon and Mars. The expected ionizing radiation dose for an astronaut is assessed along the Apollo 11 flight path to the Moon. With the two dose values, the expected and the measured total dose, the radiation shielding and the activity of the Sun are estimated. To judge the risk or safety margin the radiation effects on humans are opposed. The radiation from the Sun has to be set to zero in the computer model to achieve the published radiation dose value of the Apollo 11 flight. Galactic and cosmic particles have not been modelled either. The Apollo 11 astronauts must have been lucky that during their flight the Sun was totally quiet in the solar maximum year 1969 – and also their colleagues of the subsequent Apollo flights, i.e. until 1972, where the published dose values still require a quiet Sun. The here built mathematical model allows assessing the total dose of a journey to Mars by only changing the flight duration. Even if in the meantime much thicker and/or active radiation shielding is proposed the radiation risk of manned space flight to Moon and Mars remains still huge.
Abstract: This paper provides an overview of the radiation aspects of manned space flight to Moon and Mars. The expected ionizing radiation dose for an astronaut is assessed along the Apollo 11 flight path to the Moon. With the two dose values, the expected and the measured total dose, the radiation shielding and the activity of the Sun are estimated. To jud...
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Coupling of the Localized Wind Wall at High Latitudes to the Lower Thermosphere by Neutral Cells
Issue:
Volume 8, Issue 3, September 2020
Pages:
27-31
Received:
22 October 2020
Accepted:
7 November 2020
Published:
19 November 2020
Abstract: The recently observed Wall in the daytime zonal winds in the thermosphere from O (1S) and O (1D) emissions by the WINDII instrument on the UARS satellite in the high latitudinal region during 1994 to 1996, has been interpreted in terms of NCAR-TIGCM models. The strong westward polar wind (convergence) and weaker eastward winds equator wards of it (divergence), potentially generating localized vertical flows, overlap the dayside high density and equatorward of it low density neutral Cells’ regions in the models. The models indicate that the Cells and the Wall separating them exist at all solar and geomagnetic activities. These Cells in the thermosphere can transport neutral gas vertically down in the convergence region and up in the divergence region thus moving the associated emissions as observed in the data. Since the diameter of these Cells can reach up to 2000 km, the resulting enhanced emissions may have scale size of about 20° in latitude and longitude. The idealized transport time is under 8 minutes for up to 100 km for these observations during quiet solar and geomagnetic conditions. Once the transporting Cell’s temperature / density reaches that of the ambient atmosphere they disappear and other Cells will partake in this process at these latitudes and times.
Abstract: The recently observed Wall in the daytime zonal winds in the thermosphere from O (1S) and O (1D) emissions by the WINDII instrument on the UARS satellite in the high latitudinal region during 1994 to 1996, has been interpreted in terms of NCAR-TIGCM models. The strong westward polar wind (convergence) and weaker eastward winds equator wards of it (...
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