Archives

December 2020


Today, the National Space Council released the National Strategy for Planetary Protection. This Strategy will advance the Nation's role in the sustainable exploration of space by appropriately protecting other planetary bodies and the Earth from potentially harmful biological contamination from space exploration activities.

Planetary protection refers to the policy and practice of protecting scientific investigations by limiting biological contamination of other planetary bodies and protecting the Earth's biosphere by avoiding harmful biological contamination by returning spacecraft. This national strategy balances U.S. interests in promoting scientific discovery, human exploration, and the growth of private sector space activities, all with due consideration for public safety and applicable domestic and international obligations.

Under U.S. policy and international treaty, the goals of planetary protection are to avoid both adverse changes in Earth's environment caused by introducing extraterrestrial matter and harmful contamination of solar system bodies in order to protect their biological integrity for scientific study. The United States has long cooperated with other countries and relevant scientific communities through the Committee on Space Research (COSPAR) of the International Council for Science in developing planetary protection guidance for different categories of space missions. In the past, achieving planetary protection objectives through science-based, international-consensus guidelines proved relatively straightforward because a small number of spacefaring nations explored the solar system, predominantly through government-led and scientifically focused robotic missions.

Chemists at Scripps Research have made a discovery that supports a surprising new view of how life originated on our planet.

Using years' worth of data collected from ice-covered habitats all over the world, a Montana State University team has discovered new insights into the processes that support microbial life underneath ice sheets and glaciers, and the role those organisms play in perpetuating life through ice ages and, perhaps, in seemingly inhospitable environments on other planets.

The composition of Europa's trailing hemisphere reflects the combined influences of endogenous geologic resurfacing and exogenous sulfur radiolysis.

Characterizing habitable exoplanets and/or their moons is of paramount importance. Here we show the results of our magnetic field topological modeling which demonstrate that terrestrial exoplanet-exomoon coupled magnetospheres work together to protect the early atmospheres of both the exoplanet and the exomoon.

Over the past several decades, thousands of planets have been discovered outside of our Solar System. These planets exhibit enormous diversity, and their large numbers provide a statistical opportunity to place our Solar System within the broader context of planetary structure, atmospheres, architectures, formation, and evolution.

Around 120 million years ago, the earth experienced an extreme environmental disruption that choked oxygen from its oceans. Known as oceanic anoxic event (OAE) 1a, the oxygen-deprived water led to a minor -- but significant -- mass extinction that affected the entire globe. During this age in the Early Cretaceous Period, an entire family of sea-dwelling nannoplankton virtually disappeared.

Terrestrial extrasolar planets around low-mass stars are prime targets when searching for atmospheric biosignatures with current and near-future telescopes. The habitable-zone Super-Earth LHS 1140 b could hold a hydrogen-dominated atmosphere and is an excellent candidate for detecting atmospheric features.

The existence of liquid water within an oxidized environment on early Mars has been inferred by the Mn-rich rocks found during recent explorations on Mars. The oxidized atmosphere implied by the Mn-rich rocks would basically be comprised of CO2 and H2O without any reduced greenhouse gases such as H2 and CH4.

Scientists from Japan and NASA have confirmed the presence in meteorites of a key organic molecule which may have been used to build other organic molecules, including some used by life. The discovery validates theories of the formation of organic compounds in extraterrestrial environments.

University of Alberta researchers have found an answer to a fundamental question in genomic biology that has eluded scientists since the discovery of DNA: Within the nucleus of our cells, is the complex package of DNA and proteins called chromatin a solid or a liquid?

We report on the status of the Tierras Observatory, a refurbished 1.3-m ultra-precise fully-automated photometer located at the F. L. Whipple Observatory atop Mt. Hopkins, Arizona.

The Cassini mission to the Saturn system discovered a plume of ice grains and water vapor erupting from cracks on the icy surface of the satellite Enceladus. This moon has a global ocean in contact with a rocky core beneath its icy exterior, making it a promising location to search for evidence of extraterrestrial life in the solar system.

Mars Sample Return consists of three separate missions, the first of which is the Mars2020 rover which will land at Jezero crater on February 18, 2021. We describe here our remote sensing study of a particular unit that outcrops in Jezero crater that is likely to be part of the return sample suite.

Many biologically produced chiral molecules such as amino acids and sugars show a preference for left or right handedness (homochirality). Light reflected by biological materials such as algae and leaves therefore exhibits a small amount of circular polarization that strongly depends on wavelength.

With no dissolved oxygen to sustain animals or plants, ocean anoxic zones are areas where only microbes suited to the environment can live. "You don't get big fish," said UC Santa Barbara biogeochemist Morgan Raven. "You don't even get charismatic zooplankton." But although anoxic oceans may seem alien to organisms like ourselves that breathe oxygen, they're full of life, she said.

Using data from NASA's Cassini spacecraft, scientists at Southwest Research Institute (SwRI) modeled chemical processes in the subsurface ocean of Saturn's moon Enceladus. The studies indicate the possibility that a varied metabolic menu could support a potentially diverse microbial community in the liquid water ocean beneath the moon's icy facade.

It's known that the primary cause of the mass extinction of dinosaurs, about 66 million years ago, was a meteorite impact. But the exact mechanisms that linked the meteorite impact to mass extinction remain unclear, though climactic changes are thought to have played a part.

A device developed by scientists at the CY Cergy Paris University and Paris Observatory promises insight into how the building blocks of life form in outer space.

A study by the University of Southampton gives a new perspective on why our planet has managed to stay habitable for billions of years - concluding it is almost certainly due, at least in part, to luck. The research suggests this may lengthen the odds of finding life on so-called 'twin-Earths' in the Universe.

The magma ocean concept was first conceived to explain the geology of the Moon, but hemispherical or global oceans of silicate melt could be a widespread "lava world" phase of rocky planet accretion, and could persist on planets on short-period orbits around other stars.

Phosphorus is an element essential for life. It is fundamental to all living organisms, and is a key component of RNA, DNA, and cell membranes.

It may not be very well known, but the Arctic Ocean leaks enormous amounts of the potent greenhouse gas methane.

Scientists frequently look at how molecules behave in nature to help them design chemical processes, and that's what Queensland University of Technology (QUT) and Ghent University researchers did to create a green light-stabilised 3D polymer structure that unfolds itself when left in darkness.

Understanding the chemical interactions between water and Mg-silicates or iron is essential to constrain the interiors of water-rich planets.

Water on Mars, in the form of brines, may not be as widespread as previously thought, according to a new study by researchers at the Arkansas Center for Space and Planetary Sciences.

Charles Darwin's landmark opus, On the Origin of the Species, ends with a beautiful summary of his theory of evolution,

Juno spacecraft's spectrometer JIRAM recently observed the moon Europa in the 2-5 {\mu}m wavelength region. Here we present analysis of the average spectrum of a set of observations near 20°N and 40°W, focusing on the two forms of water-ice - amorphous and crystalline.

Recently, Nadir and Occultation for Mars Discovery (NOMAD) ultraviolet and visible spectrometer instrument on board the European Space Agency's ExoMars Trace Gas Orbiter (TGO) simultaneously measured the limb emission intensities for both [OI] 2972 and 5577 Å (green) emissions in the dayside of Martian upper atmosphere.

We published spectra of phosphine molecules in Venus' clouds, following open-science principles in releasing data and scripts (with community input leading to ALMA re-processing, now benefiting multiple projects).

Humans have taken spiders into space more than once to study the importance of gravity to their web-building. What originally began as a somewhat unsuccessful PR experiment for high school students has yielded the surprising insight that light plays a larger role in arachnid orientation than previously thought

Studies of solar radio bursts play an important role in understanding the dynamics and acceleration processes behind solar space weather events, and the influence of solar magnetic activity on solar system planets.

Finding potential life harboring exo-Earths is one of the aims of exoplanetary science. Detecting signatures of life in exoplanets will likely first be accomplished by determining the bulk composition of the planetary atmosphere via reflected/transmitted spectroscopy.

Cold Spring Harbor Laboratory (CSHL) scientists developed the world's first mobile genome sequence analyzer, a new iPhone app called iGenomics.

Scientists from Japan and the USA have confirmed the presence in meteorites of a key organic molecule which may have been used to build other organic molecules, including some used by life. The discovery validates theories of the formation of organic compounds in extraterrestrial environments.

There is a well-known gap in the sizes of small planets, between super-Earths and mini-Neptunes. This is explained by the envelope stripping of mini-Neptunes at short orbits.

The Origins Space Telescope (Origins) is one of four science and technology definition studies selected by National Aeronautics and Space Administration (NASA) in preparation of the 2020 Astronomy and Astrophysics Decadal survey in the US.

The terrestrial planets are believed to have formed by violent collisions of tens of lunar- to Mars-size protoplanets at time t<200 Myr after the protoplanetary gas disk dispersal (t_0).

From orbit, the visibility of Titan's surface is limited to a handful of narrow spectral windows in the near-infrared (near-IR), primarily from the absorption of methane gas.

On Nov. 30, 2020, NASA astronaut Kate Rubins harvested radish plants growing in the Advanced Plant Habitat (APH) aboard the International Space Station. She meticulously collected and wrapped in foil each of the 20 radish plants, placing them in cold storage for the return trip to Earth in 2021 on SpaceX's 22nd Commercial Resupply Services mission.

The most habitable region for life on Mars would have been up to several miles below its surface, likely due to subsurface melting of thick ice sheets fueled by geothermal heat, a Rutgers-led study concludes.

As humanity moves closer to the possibility of living and working millions of miles from Earth on planets like Mars, scientists are looking beyond our planet at how to acquire the materials needed to establish a self-sustaining presence in space.

This paper provides a brief summary and overview of the astrochemistry associated with the formation of stars and planets. It is aimed at new researchers in the field to enable them to obtain a quick overview of the landscape and key literature in this rapidly evolving area.

Solar Proton Events (SPEs) can cause abrupt and significant enhancements to the Martian surface radiation dose.

Special Regions on Mars are defined as environments able to host liquid water that meets certain temperature and water activity requirements that allow known terrestrial organisms to replicate, and therefore could be habitable.

Transiting compact multi-planet systems provide many unique opportunities to characterize the planets, including studies of size distributions, mean densities, orbital dynamics, and atmospheric compositions.

Electronically excited nitrogen atoms N(2D) are important species in the photochemistry of N2 based planetary atmospheres such as Titan. Despite this, few N(2D) reactions have been studied over the appropriate low temperature range.

Report by the NASA Mars Architecture Strategy Working Group (MASWG), November 2020