Hello, SFIA audio listeners, in this month's Nebula exclusive, Big Alien Theory,

we're asking the reason alien civilizations might be rare is because most aliens are huge.

To hear it and every episode early and add free, plus hours of bonus content, check

out go.nebola.tv slash Isaac Arthur and use my code, Isaac Arthur.

This episode is sponsored by Brilliant.

This year we're celebrating the 50th anniversary of mankind walking on the moon,

less than a decade after Gagarin became the first to orbit Earth, the first human anyway.

It was a dog who made the first orbit.

Yeah. human anyway. It was a dog who made the first orbit. This episode comes out on April 11th, which is National Pet Day, so I thought it would be appropriate to take a look both at how our furry friends have helped us on the road to technology and what might

be in store for them in the future. Animals, particularly our pets, played quite a large

role in humanity's rise, though often rather tragically, as was the case for Lakey, a stray dog found wandering

the streets of Moscow, who ended up being the first to orbit all pale blue dot, though

she did not survive the trip.

It's a sad reality that many critters have been sacrificed to scientific development,

and while their loss has benefited humanity quite a lot, they are

rarely acknowledged for that contribution.

The silver lining is that many of our pets have enjoyed far happier and longer lives

as a result of this knowledge too, and as we'll see today, might reap many more benefits

down the road.

Needless to say, pets have brought a lot of happiness to our lives, and research indicates

they extend those lives and help with stress and anxiety too.

Certainly they've been a source of inspiration for many folks as well, indeed it's

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