Hey Danny. What kind of scientist are you?
I work in SETI, the search of extraterrestrial intelligence.
Oh. So why haven’t we connected with aliens yet?
The best explanation for why we haven’t found life beyond Earth yet is simply that we haven’t been looking hard and long enough, and our technology has not advanced enough. There are hundreds of billions of stars in the Milky Way alone, and there are more stars in the Universe than there are grains of sand here on Earth.
And ⅕ stars has a rocky planet like earth with the right conditions for life, right?
Right! As SETI pioneer Jill Tarter is fond of saying:
You wouldn’t dip a glass in the ocean, come up with no fish inside and conclude, ‘No fish exist’. The tide pools and coral reefs of the Universe may be filled with life, we just need to keep dipping our glasses into the darkness.
That’s what I’m doing here. Just dipping my glass into the depths trying to find me a cute fish. So SETI must be a weird area to work in. Hundreds of scientists dedicate their lives to the field without any results. Do you think you’ll find them?
Well, Breakthrough Listen is a hugely ambitious program I’m working on. It’s the most comprehensive search for intelligent life beyond Earth ever undertaken. Even so, odds are we won't find a single promising signal. By the time Breakthrough Listen is finished, it will be like having examined a swimming pool’s worth of ocean water.
So it’s likely you’ll fail.
If no compelling candidate signals are found, we haven't failed. We'll still be able to place statistical constraints on how common it is for intelligent life to evolve. We may also spot new natural phenomena that warrant more study. Then it's on to the next swimming pool.
In the meantime, our data will help provide insights, at least, into some of the most profound questions in all of science. We still know almost nothing about how often life emerges from nonliving matter, or how often life develops into an intelligent society, or how long intelligent societies last.
So while we may not find any of the signs we're looking for, we can come closer to putting boundaries on how often these things occur. Even if the stars we search are silent, at least we'll have learned that we need to look farther afield for any cosmic company.
You’re leaving the star at this table pretty silent. Why don’t you give me a call when you find some cosmic company.