Each December,
tens of thousands of Earth and planetary scientists from around the globe gather to compare notes and share their latest discoveries at the annual Fall Meeting of the American Geophysical Union,
the world's premier organisation for geosciences.
And if I can fix it, I, Relimpies, try to make sure I can join them to join in the excitement.
Well, last month I succeeded.
And for the next two episodes of Discovery from the BBC World Service,
I'll give you a taste of what I heard,
from the fate of the Mississippi to the geochemical origins of life.
But this edition takes the big picture, the place of Earth as a planet in the solar system.
Space science turns out to be a major aspect of geoscience.
Stay tuned for solar weather and for moonquakes, but we're starting with planetary defence,
the idea that Asteroids orbiting close to the Sun might cross our path and cause devastating impacts,
not necessarily on the scale of the dinosaur destroying one 66 million years ago,
but enough to wipe out, say, a city.
The session on how to defend ourselves from that threat returned to a story that hit the headlines a year ago.
The discovery of an asteroid dubbed 2024 YR-4 that briefly looked
like it could smack into us in 2032.
And that was very much still in astronomers' thoughts.
Among the session participants one of America's top planetary defense experts.
I'm Andy Rifkin.