Compiled by Helmut Lammer, PhD, Senior Editor of Astrobiology, from the Austrian Academy of Sciences, this special paper collection features a report by Pham et al. that presents a semi-analytical model to evaluate the influence of impacts on the evolution of the carbon dioxide-based martian atmosphere.
The results of this study indicate that impacts alone cannot satisfactorily explain the loss of significant atmospheric mass since the Late Noachian (~ 3.7 – 4 Ga). In other words, if the martian atmosphere was much denser at about 4 Ga than at present, impact erosion was most likely not responsible for the removal of the atmosphere at that time. Terada et al. present a 3-D model to assess the effects of exposure to solar energy and winds on ion escape on early Mars 4.5 Ga, and to demonstrate how ion erosion could have led to the loss of water that might have been present on Mars.
Two reports, by Horváth et al. and Fendrihan et al., explore the existence and survival of two types of bacteria under martian surface and environmental conditions, and the types of habitats that might have existed to support these life forms.
"The results of Pham et al. and Terada et al. indicate that Mars should have lost its denser initial CO2 atmosphere very early," says Dr. Lammer, PhD, "and may have been cold and dry during most of its history. Leblanc and colleagues propose a new concept in exploratory missions with Mars Environment and Magnetic Orbiter (MEMO), which would gather data to help scientists understand how the martian surface, atmosphere, and magnetic field have evolved, and how those questions raised by Terada et al. and Pham et al. can be investigated."
In honor of the bicentenary of the birth of Charles Darwin in 2009 and the anniversary of the publication of his seminal work, On the Origin of Species, this issue of Astrobiology also includes papers describing the proposed Darwin Mission, which will take measurements on Earth-like planets outside our solar system.
"Though the final configuration of missions to study the spectra of Earth-like planets has not yet been decided," says Charles S. Cockell, PhD, Senior Editor of Astrobiology, and Professor at The Open University, Milton Keynes, UK, "Darwin represents a very important step in a consolidated scientific and technical architecture for such a mission."
Astrobiology is an authoritative peer-reviewed journal published 10 times a year in print and online. The Journal provides a forum for scientists seeking to advance our understanding of life's origins, evolution, distribution, and destiny in the universe. A complete table of contents and a full text for this issue may be viewed online at www.liebertpub.com/ast
Astrobiology is the leading peer-reviewed journal in its field. To promote this developing field, the Journal has teamed up with The Astrobiology Web to highlight one outstanding paper per issue of Astrobiology. This paper is available free online at www.liebertpub.com/ast and to visitors of The Astrobiology Web at www.astrobiology.com
Mary Ann Liebert, Inc. (www.liebertpub.com) is a privately held, fully integrated media company known for establishing authoritative peer-reviewed journals in many promising areas of science and biomedical research. Its biotechnology trade magazine, Genetic Engineering & Biotechnology News (GEN), was the first in its field and is today the industry's most widely read publication worldwide. A complete list of the firm's 60 journals, books, and newsmagazines is available at www.liebertpub.comMary Ann Liebert, Inc. 140 Huguenot St., New Rochelle, NY 10801-5215
Vicki Cohn | EurekAlert!
Further reports about: > Astrobiology > CO2 atmosphere > Earth-like moons > Earth-like planet > Erosion > Mars > Mars Environment and Magnetic Orbiter > Martian Winds > Martian environment > Senior Citizens > carbon dioxide-based martian atmosphere > changing magnetic fields > collisions with asteroids and comets > solar energy > water drive search > winds
NASA's SDO sees partial eclipse in space
29.05.2017 | NASA/Goddard Space Flight Center
Strathclyde-led research develops world's highest gain high-power laser amplifier
29.05.2017 | University of Strathclyde
The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.
The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
29.05.2017 | Earth Sciences
29.05.2017 | Life Sciences
29.05.2017 | Physics and Astronomy