Emission from a class of benzene-based molecules known as Polycyclic Aromatic Hydrocarbons (PAHs) dominates the infrared spectrum of star-forming regions. The observed emission appears to arise from the combined emission […]
PAH
Posted inAstrochemistry
Polycyclic Aromatic Hydrocarbon Formation in O-rich Planetary Nebulae
Polycyclic aromatic hydrocarbons (PAHs) have been observed in O-rich planetary nebulae towards the Galactic Bulge. This combination of oxygen-rich and carbon-rich material, known as dual-dust or mixed chemistry, is not […]
Posted inBiosignatures & Paleobiology, Fossils & Paleontology, Mars, Meteorites & Asteroids, Microbiology & Virology, Status Report
Commentary by NASA ARC’s Chris McKay on Magnetotactic Bacteria on Mars
The recent paper by Imre Friedmann and co-authors in PNAS (PNAS vol 98 page 2176, 2001) reports finding chains of magnetite that are consistent with a biological origin.