River deltas worldwide are sinking and ecosystems are struggling to adapt

Episode Transcript

Speaker 1 (00:00):
Earth may have once had a ring system. Evidence from
ancient craters suggests that Earth may have possessed a ring
similar to Saturns, which could have caused significant climate disturbances
on the planet's surface. Researchers from Monash University in Australia
hypothesize that a rocky ring formed around Earth approximately four

(00:20):
hundred sixty six million years ago, lasting for several tens
of millions of years. According to New Atlas on September sixteen.
This conclusion arises from several geological findings. During the Ordervis period,
there appears to have been an increase in the number
of impact craters on Earth. The research team mapped the

(00:42):
locations of twenty one known craters from that era, using
plate tectonic models to track their positions at the time
of impact. All of the craters seem to lie within
thirty degrees of the equator, whereas they would typically be
randomly distributed across the globebe To determine whether this was
a peculiar finding or a sampling error, the researchers calculated

(01:06):
how much land area from that time could have preserved
craters for so long. They focused on stable regions of
the crust that existed before the midpoint of the Order vision,
excluding areas that were buried, eroded, or affected by tectonic activity.
The best results were found in western Australia, Africa, parts

(01:28):
of North America, and Europe. The team then used the
same tectonic model to trace back where those regions were
located on Earth during the Order vision, only thirty percent
of the suitable land was near the equator. The concentration
of all twenty one craters within this narrow band raised
questions about what might have caused the meteorite impacts to

(01:51):
cluster around the equator. If Earth had captured an asteroid
passing by four hundred sixty six million years ago, it
could have caused the asteroid to break into pieces and
form a ring, with debris falling onto the planet primarily
at the equator for several tens of millions of years.
The ring hypothesis could also explain several other mysteries from

(02:14):
that time. The meteorite fragments in the craters show signs
of having spent little time in space before striking Earth,
consistent with material from a relatively recent breakup of a
large asteroid that created the ring. About twenty million years later,
Earth entered the Henantian Glaciation, when temperatures drop to their

(02:36):
lowest levels in half a billion years. Due to Earth's
axial tilt relative to the Sun, the equatorial ring could
have cast a shadow over part of the planet's surface,
potentially triggering a global cooling event. This new hypothesis raises
the possibility that ring systems are a phase that Earth

(02:56):
and other planets may undergo multiple times in their lifetime times. Ultimately,
Saturn's rings are estimated to be around ten million years old,
indicating that Earth might have experienced this phenomenon first. Mars
is currently breaking apart one of its moons, which could
form a new ring system in the next twenty to

(03:17):
forty million years. The research team plans to model the
process of asteroid fragmentation and ring formation, as well as
how such a ring might evolve over time and its
impact on climate. The findings were published in the journal
Earth and Planetary Science Letters,