Related papers: Cosmic Biology in Perspective
The theory of cometary panspermia, developed by the late Sir Fred Hoyle and the present author argues that life originated cosmically as a unique event in one of a great multitude of comets or planetary bodies in the Universe. Life on Earth…
Comets contain abundant amounts of organic and inorganic species. Many of the volatile molecules in comets have also been observed in the interstellar medium and some of them even with similar relative abundances, indicating formation under…
The transformation of organic molecules into the simplest self-replicating living system,a microorganism, is accomplished from a unique event or rare events that occurred early in the Universe. The subsequent dispersal on cosmic scales and…
Since its inception six decades ago, astrobiology has diversified immensely to encompass several scientific questions including the origin and evolution of Terran life, the organic chemical composition of extraterrestrial objects, and the…
Despite great advances in our understanding of the formation of the Solar System, the evolution of the Earth, and the chemical basis for life, we are not much closer than the ancient Greeks to an answer of whether life has arisen and…
How can scientists conclude with high confidence that an exoplanet hosts life? As telescopes come on line over the next 20 years that can directly observe photons from terrestrial exoplanets, this question will dictate the activities of…
The past century of interstellar dust has brought us from first ignoring it to finding that it plays an important role in the evolution of galaxies. Current observational results in our galaxy provide a complex physical and chemical…
The oft-repeated claim that life is written into the laws of nature are examined and criticized. Arguments are given in favour of life spreading between near-neighbour planets in rocky impact ejecta (transpermia), but against panspermia,…
I examine some recent findings in cosmology and their potential implications for the emergence of life in the universe. In particular, I discuss the requirements for carbon-based life, anthropic considerations with respect to the nature of…
Contrary to popular belief, the interstellar medium (ISM) is not empty; it is filled with atoms, dust particles, and molecules. Some of these molecules may have been the very building blocks of life that, delivered to Earth via comets and…
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…
The evolution of life has been a big enigma despite rapid advancements in the fields of biochemistry, astrobiology, and astrophysics in recent years. The answer to this puzzle has been as mind-boggling as the riddle relating to evolution 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…
The existence of intelligent, interstellar traveling and colonising life is a key assumption behind the Fermi Paradox. Until recently, detecting signs of life elsewhere has been so technically challenging as to seem almost impossible.…
One of the major goals for astronomy in the next decades is the remote search for biosignatures (i.e.\ the spectroscopic evidence of biological activity) in exoplanets. Here, we adopt a Bayesian statistical framework to discuss the…
Whereas the Solar System has Mars and Europa as the best candidates for finding fossil/extant life as we know it - based on complex carbon compounds and liquid water - the 263 (non-pulsar) planetary systems around other stars as known at 15…
As of 2025, over 6000 planets are known to orbit stars other than our Sun. We can measure their sizes and orbital periods, infer their masses and temperatures, and constrain their compositions. Based on these data, about 1% of extrasolar…
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…
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…
Thousands of exoplanets orbit nearby stars, showcasing a remarkable diversity in mass, size, and orbits. With the James Webb Space Telescope now operational, we are observing exoplanet atmospheres and aiming to reach down to small,…