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.

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They say there's nothing new under the sun.

But what if someday Earth was flung away from our sun. So today we're going to be asking what would happen if Earth got ejected from its orbit around our sun and if we could survive in the depths of interstellar space.

As we will see today, this possibility is not as unlikely as it sounds, nor as inevitable

or doom as folks would tend to think, particularly from non-natural events like us intentionally

moving our planet, which we will also discuss today.

To begin with, there have been frequent arguments about what planets actually are for a couple

centuries now,

which tends to interfere with the count. But while the number of objects we classify as planets

might change, we generally accept that the objects themselves do not. But this isn't entirely

true, and indeed if you skip backaways, we would find the planets have changed in their number

and their properties, and indeed some researchers believe that at some point in the early

days, the solar system may even have had some super-Earths, plants more massive than Earth but

less than Neptune, which clearly are not around anymore.

We looked at those recently and how capital they might

or might not be, and our solar system would be a very different place indeed if we'd had them

...