Phil Appleton Quotations

(It) has left the Cartwheel galaxy with a crisp, bright ring around a zone of relative calm.

The dramatic plunge has left the Cartwheel Galaxy with a crisp, bright ring around a zone of relative calm.

It's like dropping a stone into a pond, only in this case, the pond is the galaxy, and the wave is the compression of gas. Each wave represents a burst of star formation, with the youngest stars found in the outer ring.