This is Science Friday. I'm Ira Flato, broadcasting today from the studios of KCLU on the campus of California Lutheran University in Thousand Oaks, California.

Later in the hour, an update on where world nations stand on curbing carbon emissions and avoiding a climate catastrophe.

But first, Thursday morning, two astronauts on route to the International Space Station

had to abort their launch after a booster rocket malfunction.

They made an emergency descent back to Earth, and I'm happy to report both they're doing well,

both landing safely.

Rachel Feldman, Science Editor at Popular Science is here to bring us up to date on the launch

and other selected short subjects in science.

Welcome back, Rachel.

Thanks for having me, Ira.

Anything more about what went wrong there?

Yeah, so we know that about two minutes into the launch, there was some kind of booster failure,

and they had to undergo what's known as a ballistic descent, which is so-called because usually they make

kind of a shallow angle as they come down to create a little bit of lift and take away some

of the force on the astronauts

during the landing. And this is where the rocket is really coming down more like a projectile.

And this has happened before, but only ever during landings, which of course appears a lot

less dramatic because they were supposed to come back down to the

ground in the first place. So this is the first time they've ever had to make such an aborted

landing during a launch. And the Russian space agency said immediately they would begin investigating.

And so far, that's all we know. Well, the good news about it is that it worked,

right? Right. And again, this is rare, but the kind of thing that astronauts train for all the

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