Footprints of the newly discovered Vela supernova in Antarctic ice cores?

The recently discovered, nearby young supernova remnant in the southeast corner of the older Vela supernova remnant may have been seen in measurements of nitrate abundances in Antarctic ice cores. Such an interpretation of this 20-year-old ice-core data would provide a more accurate dating of this supernova than is possible purely using astrophysical techniques. It permits an inference of the supernova's Ti-44 yield purely on an observational basis, without reference to supernova modelling. The resulting estimates of the supernova distance and light-arrival time are 200 pc and 700 years ago, implying an expansion speed of 5000 km/s for the supernova remnant. Such an expansion speed has been argued elsewhere to imply the explosion to have been a 15 M. Type II supernova. This interpretation also adds new evidence to the debate as to whether nearby supernovae can measurably affect nitrate abundances in polar ice cores. (C) 2000 Elsevier Science B.V. All rights reserved.