Archives

July 2019


Young terrestrial planets can capture or outgas hydrogen-rich atmospheres with tens to hundreds of bars of H2, which persist for 100 Myrs or longer.

The GJ 357 system harbors 3 planets orbiting a bright, nearby M2.5V star at 9.44pc. The innermost planet GJ 357 b (TOI-562.01) is a hot transiting Earth-size planet with Earth-like density, which receives about 12 times the irradiation Earth receives from the Sun, and was detected using data from TESS.

Atmospheric heat redistribution shapes the remote appearance of rocky exoplanets but there is currently no easy way to predict a planet's heat redistribution from its physical properties.

Photosynthesis offers a convenient means of sustaining biospheres. We quantify the constraints for photosynthesis to be functional on the permanent nightside of tidally locked rocky exoplanets via reflected light from their exomoons.

From 2004 to 2017, the Cassini spacecraft orbited Saturn, completing 127 close flybys of its largest moon, Titan.

The evolution of different forms of photosynthetic life has profoundly altered the activity level of the biosphere, radically reshaping the composition of Earth's oceans and atmosphere over time.

We analyze the light curve of the M5.5 dwarf Proxima Centauri obtained by the TESS in Sectors 11 and 12. In the ≈50 day-long light curve we identified and analyzed 72 flare events.

The emergence of oxygenic photosynthesis created a new niche with dramatic potential to transform energy flow through Earth's biosphere.

Tiny gas-filled bubbles in the porous rock found around hot springs are thought to have played an important role in the origin of life.

Structures inside rare bacteria are similar to those that power photosynthesis in plants today, suggesting the process is older than assumed.

Though it remains unknown how life began, there is a community of scientists who suspect it occurred in or around deep sea hydrothermal environments.

Inspired by the processes of cellular differentiation observed in developmental biology, an interdisciplinary team of researchers at the University of Bristol have demonstrated a new spontaneous approach to building communities of cell-like entities (protocells) using chemical gradients.

The Kepler data show that habitable small planets orbiting Red Dwarf stars (RDs) are abundant, and hence might be promising targets to look at for biomarkers and life. Planets orbiting within the Habitable Zone of RDs are close enough to be tidally locked.

Before life began on Earth, the environment likely contained a massive number of chemicals that reacted with each other more or less randomly, and it is unclear how things as complex as cells could have emerged from such chemical chaos.

Potential microbial contamination of Martian moons, Phobos and Deimos, which can be brought about by transportation of Mars ejecta produced by meteoroid impacts on the Martian surface, has been comprehensively assessed in a statistical approach, based on the most probable history of recent major gigantic meteoroid collisions on the Martian surface.

The low temperatures and high ultraviolet (UV) radiation levels at the surface of Mars today currently preclude the survival of life anywhere except perhaps in limited subsurface niches.

Ancient hydrology is recorded by sedimentary rocks on Mars. The most voluminous sedimentary rocks that formed during Mars' Hesperian period are sulfate-rich rocks, explored by the Opportunity rover from 2004-2012 and soon to be investigated by the Curiosity rover at Gale crater.

The search for complex organic molecules in the interstellar medium (ISM) has revealed species of ever greater complexity.

This paper presents a case study of microbe transportation in the Mars-satellites system. We examined the spatial distribution of potential impact-transported microbes on the Martian moons using impact physics by following a companion study (Fujita et al.).

We present ALMA observations of organic molecules towards five low-mass Class 0/I protostellar disk candidates in the Serpens cluster.

Kepler, K2, TESS, and similar time-domain photometric projects, while designed with exoplanet detection in mind, are also well-suited projects for searches for large artificial structures orbiting other stars in the Galaxy.

WISE, Gaia, and JWST provide an opportunity to compute the first robust upper limits on the energy supplies of extraterrestrial civilizations, both for stars in the Galaxy (Kardashev Type II civilizations) and for other galaxies (Kardashev Type III civilizations).

The search for life beyond the Solar System-a major part of the Planetary Systems thematic area of the Astro2020 Decadal process-includes the search for technological life.

The search for life in the universe is a major theme of astronomy and astrophysics for the next decade.

We present a three-species multi-fluid MHD model (H+, O+ and e−), endowed with the requisite upper atmospheric chemistry, that is capable of accurately quantifying the magnitude of oxygen ion losses from "Earth-like" exoplanets in habitable zones, whose magnetic and rotational axes are roughly coincidental with one another.

Synthetic biologists seek to create new life with forms and functions not seen in nature.

A boiling point of 5900 degrees Celsius and diamond-like hardness in combination with carbon: tungsten is the heaviest metal, yet has biological functions - especially in heat-loving microorganisms.

In recent years, the idea of life on other planets has become less far-fetched. NASA announced June 27 that it will send a vehicle to Saturn's icy moon, Titan, a celestial body known to harbor surface lakes of methane and an ice-covered ocean of water, boosting its chance for supporting life.

Scientists have developed a new method for detecting traces of primordial life in ancient rock formations using potassium.

High in the Andes Mountains, dagger-shaped ice spires house thriving microbial communities, offering an oasis for life in one of Earth's harshest environments as well as a possible analogue for life on other planets.

Peptides, one of the fundamental building blocks of life, can be formed from the primitive precursors of amino acids under conditions similar to those expected on the primordial Earth, finds a new UCL study.

Potential precursors to life on Earth form from a variety of complex mixtures, according to a team of scientists who say this could point to the development of building blocks crucial to forming genetic molecules for the origins of life on Earth.

The late stages of stellar evolution from asymptotic giant branch stars to planetary nebulae are now known to be an active phase of molecular synthesis.

The discovery of the ubiquity of habitable extrasolar planets, combined with revolutionary advances in instrumentation and observational capabilities, have ushered in a renaissance in the millenia-old quest to answer our most profound question about the Universe and our place within it - Are we alone?

Due to its absence of an atmosphere and relative geological inertness, the Moon's surface records past impacts of objects from the Solar system and beyond.

The prioritization and improvement of ethics, planetary protection, and safety standards in the astro-sciences is the most critical priority as our scientific and exploratory capabilities progress, both within government agencies and the private sector.

Traditional searches for extraterrestrial intelligence (SETI) or "technosignatures" focus on dedicated observations of single stars or regions in the sky to detect excess or transient emission from intelligent sources.

When Carl Sagan observed the Earth during a Gallileo fly-by in 1993, he found a widely distributed surface pigment with a sharp reflection edge in the red part of the spectrum, which, together with the abundance of gaseous oxygen and methane in extreme thermodynamic disequilibrium, were strongly suggestive of the presence of life on Earth.

There have been periodic efforts in recent decades to search for extraterrestrial intelligence (SETI), especially by trying to find an extraterrestrial (ET) radio signal or other technosignature in space. Yet, no such technosignatures have been found.

Researchers from Southern Methodist University (SMU) could help determine if Saturn's icy moon -- Titan -- has ever been home to life long before NASA completes an exploratory visit to its surface by a drone helicopter.

The processes behind the release and consumption of methane on Mars have been discussed since methane was measured for the first time for approx. 15 years ago.

The middle of the South Pacific is as far away from land as you can possibly get. Solar irradiance is dangerously high, reaching a UV-index that is labelled 'extreme'.

Terrestrial planets covered globally with thick oceans (termed ocean planets) in the habitable zone were previously inferred to have extremely hot climates in most cases.

One of the great attractions of the island of Santorini, in Greece, lies in its spectacular volcanic landscape, which also contains places similar to those of Mars. A team of European and U.S. scientists has discovered it after analysing basaltic rocks collected in one of its coves.

Sheding light on one of the most enduring mysteries of science: How did metabolism - the process by which life powers itself by converting energy from food into movement and growth - begin?

The International Space Station, like all human habitats in space, has a nagging mold problem. Astronauts on the ISS spend hours every week cleaning the inside of the station's walls to prevent mold from becoming a health problem.

The ocean as we understand it today was shaped by a global evolutionary regime shift around 170 million years ago, according to new research.