Is Interstellar Travel Impossible?

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Space is pretty deadly. But is it so deadly that we’re effectively imprisoned in our solar system forever? Many have said so, but a few have actually figured it out.

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Hosted by Matt O'Dowd
Written by Matt O'Dowd
Post Production by Leonardo Scholzer, Yago Ballarini, Pedro Osinski, Adriano Leal & Stephanie Faria
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[zelexi]

Possible solution #2. Increase human lifespan such that interstellar travel is just a matter of making enough Netflix content for the trip.

[Timesend]

The irony of having to be aware of things so small whilst travelling through something so vast

[Evan.the.Butler]

Given how many times ancient humans sailed into the ocean with little chance of finding anything, I think we'd try interstellar travel regardless of the risk

[TheNightWatcher]

I think the best solution is that intelligent life is so rare that even if others are out there they’re so separated by space and time that we will never interact and so we’re still effectively alone.

[greenseer]

One important thing that isn't brought up in this video: any ship travelling at relativistic speeds will need to turn around and decelerate while in the interstellar medium (or else they'll just zip past the destination). This complicates designs that involve only forward-facing shielding.

[GundamAngelicDevil]

I love how even in interstellar space, we still have to have a spacecraft that's "aerodynamic".

[pwp]

Could anyone in 1923 have envisioned the internet? Technology advances, begetting more advances and in a century, perhaps one of our descendants is sitting on Centauri having a refreshing drink.

[benhoffman]

A couple problems here-
1: It takes time to reach relativistic speeds. So side shielding is unavoidable
2: The front of the ship is the engines when you want to slow down.

[distantignition]

I love feeling like he's about to say "spacetime" at the end. "He's doing it. Here it comes. And.... there it is."

[DavidAllen_]

It would be pretty ironic if our ship arrived at the next nearest star looking like Oumuamua because of all the interstellar particles. One habited planet will say "hey, that's an odd looking asteroid!"

[lbrw]

Fermi was talking about the lack of radio signals, not visitors. Another danger of high speed, interstellar travel is the blue shift of light coming toward the ship from source that lies in the direction the ship is moving. At high enough speeds, the blue shifted light will effectively strike the ship as deadly gamma rays.

[dayceem]

Proxima Centuri crew: "Houston, it's not as habitable as we thought here. We're considering another system 10 light years further out. We'll let you know."
Reply, 8.5 years later: "Righto. Standing by."

[daps]

"The universe may be trying to kills us, but it's not trying quite hard enough..." I just love that line. It makes me want to say, "I see you and raise you." Challenge accepted.

[knurlgnar]

You know what's even harder than accelerating to relativistic speeds? Stopping. All of the energy required to slow down needs to come from the spacecraft itself rather than a ground based source.

[stewarthill]

Wow, thanks Matt for providing this very interesting and informative video. I’m now going to be watching and listening to your YouTube site.

[MercyBot]

You just gotta fold a piece of paper in half and stick a pencil through it.

[Griffolion]

Reminds me of that quote of The Expanse with the people building the generation ship to go to Alpha Centauri: "When all the air you'll have is what you bring with you, the loss tolerances are going to be tighter."

[berg]

You see, I love this idea. People always talk about the Fermi Paradox and I have to be that guy that says, “Maybe it’s because it takes too much effort to travel interstellar?”

[vabshroff]

It seems there are too much barriers for intersteller travels...but the positive part is that, we ourselves are also shielded by the same from alien invasion

[jameskirk]

Thank you! Very informative, I had no idea.