Results tagged “Astrochemistry”

Small hydrocarbons are an important organic reservoir in protostellar and protoplanetary environments. Constraints on desorption temperatures and binding energies of such hydrocarbons are needed for accurate predictions of where these molecules exist in the ice vs. gas-phase during the different stages of star and planet formation.

Typically, H3+ is formed by collisions involving hydrogen gas, but its chemistry at the molecular level is relatively unknown. When organic molecules are hit by a laser pulse, they are ionized and the reaction begins.

Some of the exoplanets so far observed show featureless or flat transmission spectra, possibly indicating the existence of clouds and/or haze in their atmospheres.

Water ice is abundant in protoplanetary disks. Its sticking properties are therefore important during phases of collisional growth. In this work, we study the sticking and rolling of 1.1 mm ice grains at different temperatures. We find a strong increase in sticking between 175 K to 200 K which levels off at higher temperatures.

In the laboratory, the photo-and thermochemical evolution of ices, made of simple molecules of astrophysical relevance, always leads to the formation of semi-refractory water-soluble organic residues.

We report a computational study of the stability and infrared (IR) vibrational spectra of neutral and singly ionised fullerene cages containing between 44 and 70 carbon atoms.

Young stars are often surrounded by a protoplanetary disk where planets are forming. Astronomers study the composition of protoplanetary disks to better understand how planets, like Earth, formed and evolved into their modern chemical composition.

Protoplanetary disks are dust-rich structures around young stars. The crystalline and amorphous materials contained within these disks are variably thermally processed and accreted to make bodies of a wide range of sizes and compositions, depending on the heliocentric distance of formation.

The cometary materials are thought to be the reservoir of primitive materials in the solar system. The recent detection of glycine and CH3NH2 by the ROSINA mass spectrometer in the coma of 67P/Churyumov-Gerasimenko suggests that amino acids and their precursors have been formed in such an early evolutionary phase of the Solar System.

The C2H4O2 isomers have been previously investigated primarily via disparate sets of observations involving single dish and array measurements.

Organics in the Solar System

Complex organics are now commonly found in meteorites, comets, asteroids, planetary satellites, and interplanetary dust particles. The chemical composition and possible origin of these organics are presented.

Theories of a pre-RNA world suggest that glycolonitrile (HOCH2CN) is a key species in the process of ribonucleotide assembly, which is considered as a molecular precursor of nucleic acids.

Rocky planets orbiting red dwarf stars may be bone dry and lifeless, according to a new study using NASA's Hubble Space Telescope. Water and organic compounds, essential for life as we know it, may get blown away before they can reach the surface of young planets.

Using the infrared satellite AKARI, a Japanese research team has detected the existence of water in the form of hydrated minerals in a number of asteroids for the first time.

New research suggests that the sugar molecule that puts the "D" in DNA -- 2-deoxyribose -- could exist in the far reaches of space. A team of NASA astrophysicists were able to create DNA's sugar in laboratory conditions that mimic interstellar space.

In their search for life in solar systems near and far, researchers have often accepted the presence of oxygen in a planet's atmosphere as the surest sign that life may be present there. A new Johns Hopkins study, however, recommends a reconsideration of that rule of thumb.

Late Delivery of Nitrogen to Earth

Atmospheric nitrogen may be a necessary ingredient for the habitability of a planet since its presence helps to prevent water loss from a planet. The present day nitrogen isotopic ratio, 15N/14N, in the Earth's atmosphere is a combination of the primitive Earth's ratio and the ratio that might have been delivered in comets and asteroids.

The origin of the reservoirs of water on Earth is debated. The Earth's crust may contain at least three times more water than the oceans.

A new study led by The Australian National University (ANU) has investigated the nature of a cosmic phenomenon that slows down star formation, which helps to ensure the universe is a place where life can emerge.

The formyl radical HCO has been proposed as the basic precursor of many complex organic molecules such as methanol (CH3OH) or glycolaldehyde (CH2OHCHO).

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