Atmospheric Ignition Chemistry of Green Hypergolic Bipropellant 1-Ethyl-3-Methylimidazolium Cyanoborohydride - Hydrogen Peroxide in an Acoustic Levitator: Exploring a Potent Universal Propellant.

Hypergolic ionic liquids (HILs) represent a critical pool of reactive ionic liquids which ignite spontaneously in absence of oxygen when mixed with an oxidizer such as white fuming nitric acid (WFNA, HNO3) or hydrogen peroxide (H2O2). These HILs have emerged as greener alternative to the toxic hydrazine family of fuels for operations in space under anaerobic conditions. Here, we report on the unusual atmospheric ignition chemistry of the 1-ethyl-3-methylimidazolium cyanoborohydride ([EMIM][CBH])-H2O2 bipropellant while comparing with the parent hypergolic reaction by exploiting a chirped-pulse triggered droplet merging technique in an ultrasonic levitation apparatus under controlled environment.

Unraveling the Unusual Chemistry of the Hydrogen-Peroxide-Driven Hypergolic Ignition of a Cyanoborohydride Ionic Liquid as a Next-Generation Green Space Propellant.

Hypergolic ionic liquids (HILs) have emerged as promising self-igniting green space propellants in combination with an oxidizer, replacing toxic hydrazine family rocket fuels. Despite numerous new HILs being reported in the literature, there is no systematic study addressing the key reaction mechanism of such hypergolic ignition. Here, the first comprehensive molecular level understanding of this ignition reaction is revealed, exploring a 1-ethyl-3-methylimidazolium cyanoborohydride-hydrogen peroxide ([EMIM][CBH]-HO) green bipropellant pair by a novel chirped-pulse droplet-merging technique in a controlled environment.

Ionizing radiation exposure on Arrokoth shapes a sugar world.

The Kuiper Belt object (KBO) Arrokoth, the farthest object in the Solar System ever visited by a spacecraft, possesses a distinctive reddish surface and is characterized by pronounced spectroscopic features associated with methanol. However, the fundamental processes by which methanol ices are converted into reddish, complex organic molecules on Arrokoth's surface have remained elusive. Here, we combine laboratory simulation experiments with a spectroscopic characterization of methanol ices exposed to proxies of galactic cosmic rays (GCRs).

Thermal Synthesis of Carbamic Acid and Its Dimer in Interstellar Ices: A Reservoir of Interstellar Amino Acids.

Reactions in interstellar ices are shown to be capable of producing key prebiotic molecules without energetic radiation that are necessary for the origins of life. When present in interstellar ices, carbamic acid (HNCOOH) can serve as a condensed-phase source of the molecular building blocks for more complex proteinogenic amino acids. Here, Fourier transform infrared spectroscopy during heating of analogue interstellar ices composed of carbon dioxide and ammonia identifies the lower limit for thermal synthesis to be 62 ± 3 K for carbamic acid and 39 ± 4 K for its salt ammonium carbamate ([HNCOO][NH]).

Quantum Tunneling Mediated Low-Temperature Synthesis of Interstellar Hemiacetals.

Sugars and sugar-related molecules are ubiquitous in carbonaceous meteorites and in star-forming regions, but the underlying mechanisms of their formation have remained largely elusive. Herein, we report an unconventional synthesis of the hemiacetal, (/)-1-methoxyethanol (CHOCH(OH)CH), through quantum tunneling mediated reactions in low-temperature interstellar model ices composed of acetaldehyde (CHCHO) and methanol (CHOH). The detection of racemic 1-methoxyethanol through a bottom-up synthesis from simple, abundant precursor molecules within interstellar ices represents a vital starting point to the formation of complex interstellar hemiacetals.