相关论文: Astrophysical and Biological Constraints on Radiop…
Astronomically, there are viable mechanisms for distributing organic material throughout the Milky Way. Biologically, the destructive effects of ultraviolet light and cosmic rays means that the majority of organisms arrive broken and dead…
By obtaining the assumption that planetary dust particles can escape from the gravitational attraction of a planet, we consider the possibility for the dust grains to leave the star's system by means of the radiation pressure. By taking the…
We investigate whether it is possible that viable microbes could have been transported to Earth from the planets in extra-solar systems by means of natural vehicles such as ejecta expelled by comet or asteroid impacts on such planets. The…
As discoveries of multiple planets in the habitable zone of their parent star mount, developing analytical techniques to quantify extrasolar intra-system panspermia will become increasingly important. Here, we provide user-friendly…
We study the process of panspermia in Milky Way-like galaxies by modeling the probability of successful travel of organic compounds between stars harboring potentially habitable planets. To this end, we apply the modified habitability…
The results obtained in these experiments have revealed a remarkable resistance of extremophilic bacteria and archaea against different radiation sources (VUV, solar wind simulants, X rays) whenever protected by microsized carbonaceus…
The closest potentially habitable worlds outside our Solar system orbit a different kind of star than our Sun: smaller red dwarf stars. Such stars can flare frequently, bombarding their planets with biologically damaging high-energy UV…
We explore if carbon-based macromolecules (such as DNA) in the environments of stars other than the Sun are able to survive the effects of photospheric stellar radiation, such as UV-C. Therefore, we focus on main-sequence stars of spectral…
In this chapter, we present an overview of sources of biologically relevant astrophysical radiation and effects of that radiation on organisms and their habitats. We consider both electromagnetic and particle radiation, with an emphasis on…
We present an analytic model to estimate the total number of rocky or icy objects that could be captured by planetary systems within the Milky Way galaxy and result in panspermia should they harbor life. We estimate the capture rate of…
Motivated by the recent discovery of interstellar objects passing through the solar system, and by recent developments in dynamical simulations, this paper reconsiders the likelihood for life bearing rocks to be transferred from one…
Ultraviolet radiation is known to inhibit photosynthesis, induce DNA destruction and cause damage to a wide variety of proteins and lipids. In particular, UV radiation between 200-300 nm becomes energetically very damaging to most of the…
This paper considers the lithopanspermia hypothesis in star forming groups and clusters, where the chances of biological material spreading from one solar system to another is greatly enhanced (relative to the field) due to the close…
Spreading of life-bearing spores across the Galaxy (panspermia) may be easier than is usually acknowledged.
A fundamental astrobiological question is whether life can be transported between extrasolar systems. We propose a new strategy to answer this question based on the principle that life which arose via spreading will exhibit more clustering…
Panspermia is the hypothesis that life originated on Earth from the bombardment of foreign interstellar ejecta harboring polyextremophile microorganisms. Since the 2017 discovery of the interstellar body 'Oumuamua (1I/2017 U1) by the…
The hypothesis that Earth was intentionally seeded with life by a preceding extraterrestrial civilization is believed to be currently untestable. However, analysis of the situation where humans themselves embark on seeding other planetary…
Material from the surface of a planet can be ejected into space by a large impact, and could carry primitive life forms with it. We performed n-body simulations of such ejecta to determine where in the Solar System rock from Earth and Mars…
High-energy astrophysical events, particularly Gamma Ray Bursts (GRBs), have been proposed as significant contributors to mass extinction events on Earth-like planets in most of the galaxy, internal to our radius in it. This paper examines…
The proposition that life can spread from one planetary system to another (interstellar panspermia) has a long history, but this hypothesis is difficult to test through observations. We develop a mathematical model that takes parameters…