Figure 1
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| Panel A of Inset | Panel B of Inset | Panel C of Inset |
This artist's concept illustrates how planetary systems arise out of
massive collisions between rocky bodies. New findings from NASA's Spitzer
Space Telescope show that these catastrophes continue to occur around
stars even after they have developed full-sized planets, when they are as
old as one hundred million years. For reference, our own Sun, at 4.5
billion years old, is far past this late stage of planet formation.
In this image, a young star is shown circled by full-sized planets, and
rings of dust beyond. These rings, also called "debris discs," arise when
embryonic planets smash into each other. One of these collisions is
illustrated in the inset of Figure 1.
Spitzer was able to see the dust generated by these collisions with its
powerful infrared vision.
