Tracing the trajectory of a 66 million-year-old asteroid impact

How to make a big hole fast.

Enlarge / How to make a big
hole fast. (credit: Collins et
al./Nature Communications
)

You know that scene in every forensic crime drama where someone
works out the angle the bullet was fired from and points back to
the source? In the case of the Chicxulub asteroid impact and the
end-Cretaceous mass extinction 66 million years ago, there’s no
mystery about the shooter. (Space did it.) But the trajectory is
interesting for other reasons, and researchers have long been
trying to trace the path back out of the crater off the Yucatán
coast.

Unsurprisingly, 66 million years have taken their toll on the
crater, so researchers have offered several very different answers.
Did the asteroid hit from the southeast at a very low angle? Did it
come from the southwest at a moderate angle? Many studies that
needed to model the impact have simply defaulted to a 90-degree
strike and avoided the whole argument. The details actually matter,
though, and precisely which rocks get vaporized—and which
climate-changing gases they release—depends on that impact
angle.

A lot of new research on the crater has been published recently
thanks to a major expedition that included drilling a rock core
down through the crater’s peak ring. (Impacts this violent leave
a raised ring in the center rather than a single peak.) A new paper
led by Imperial College London’s Gareth Collins
makes the latest contribution using model simulations to see what
impact angle best matches the observed characteristics of the
crater.

Read 9 remaining
paragraphs

Source: FS – All – Science – News
Tracing the trajectory of a 66 million-year-old asteroid
impact