Article

Astronomy. The cradle of the solar system.

Department of Physics and Astronomy, Arizona State University, Tempe, AZ 85287-1504, USA.
Science (Impact Factor: 31.2). 06/2004; 304(5674):1116-7. DOI: 10.1126/science.1096808
Source: PubMed

ABSTRACT The recent discovery of decay products of 60Fe in meteorites challenges
conventional wisdom about the environment in which the Sun and planets
formed. Rather than a region like the well-studied Taurus-Auriga
molecular cloud, the solar system must have formed instead in a region
more like the Eagle nebula--a region that contained one or more massive
stars that went supernova, injecting newly synthesized radionuclides
into the nascent solar system. In their Perspective, Hester et al.
discuss a scenario by which the solar system--and other low-mass stars
like the Sun--could have formed. Radiant energy from massive, luminous
stars first compresses surrounding interstellar gas, triggering the
formation of Sun-like stars, then quickly disperses this material,
exposing newborn stars and their protoplanetary disks to harsh radiation
from the massive stars. When the massive stars go supernova, they pelt
surrounding protoplanetary disks with ejecta laden with the products of
stellar nucleosynthesis that are required to explain the isotopic
composition we see today.

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