The Sun’s Crowded Delivery Room
• Telescopic
observations suggest
that stars, even
isolated ones like the
Sun, form in clusters
• Meteorite studies can
test this idea and give
additional information
about events leading to
formation of the Solar
System
Moon
Cluster of new stars in the
constellation of Vela (Courtesy of
European Southern Observatory)
www.psrd.hawaii.edu/July07/iron-60.html
The Sun’s Crowded Delivery Room
• Precise analyses by Martin
Bizzarro and his colleagues
show that Earth, Mars, and
chondritic meteorites contain
evidence for the presence of
60Fe (given by the 0.0 value
of ε60Ni, the decay product of
60Fe)
• In contrast, differentiated
meteorites, which formed 1
My after initial solar system
formation, have no evidence
for 60Fe (low ε60Ni)
www.psrd.hawaii.edu/July07/iron-60.html
The Sun’s Crowded Delivery Room
• In spite of having had no 60Fe,
differentiated meteorites did
contain 26Al, as did most early
solar system materials
• Martin Bizzarro and his
colleagues suggest:
– 26Al was incorporated into
the interstellar cloud that
gave birth to the Sun when
massive stars spewed
strong stellar winds
– 60Fe was added a million
years later when the star
exploded
Wolf-Rayet star --
Stellar winds blowing from a massive
Wolf-Rayet star (brightest star near
center) in NGC 2359 Nebula. Courtesy
of P. Berlind & P. Challis, HarvardSmithsonian Center for Astrophysics.
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