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Four Earth-sized planets detected orbiting the nearest sun-like star

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Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#111

Post by abecedarius »

jandrese wrote: post #98
ajross wrote: post #26

Earlier quoted context omitted.

An "EmDrive" is a pseudoscience device. Poor calculation rigor is not the biggest error component in that number.

It's a good example of the problem though. Any drive that relies on reaction mass will take too long to cross the distance to even nearby stars. The rocket equation kills the plan unless you're willing to make an absolutely ridiculous starship. So you need a reactionless drive, which thus far is entirely science fiction. This is even before you start thinking about micrometeorites in the way (which long transits incr…

There's a bunch of ideas that the rocket equation doesn't apply to: https://en.wikipedia.org/wiki/Interstellar_travel#Non-rocket...

Yes, it's hard at our current tech level. But not nearly hard enough to explain the Fermi thing. I mean, take your scenario of solar system development: it'd be natural to exploit the Kuiper Belt and then the Oort, and the Oort blends into interstellar travel, as Freeman Dyson pointed out -- still quick on a geological timescale.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#112

Post by EthanHeilman »

moonbug22 wrote: post #106
ExactoKnight wrote: post #103

Earlier quoted context omitted.

The other project that needs to become a reality FAST is the construction of a telescope large enough to measure the spectra of exoplanets. Because once you find a habitable planet with oxygen in its atmosphere, you now have an irrefutable and pressing case to move fast with Breakthrough Starshot. Sadly it's going to likely a require 100metre telescope mirror or larger, and current science funding only has a 30metre…

You know about the SKA, right?

At first I thought you were making a joke about the human race prioritizing Ska[0] over new telescopes, but then I realized I wasn't on reddit and saw the "the".

What is SKA? Super K? Aperture?

[0]: https://en.wikipedia.org/wiki/Ska

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#113

Post by jogjayr »

svachalek wrote: post #33
h4l0 wrote: post #2

Hearing distances like 12 light years makes you think if it is ever possible to travel there. However, when you start to think about it, nihilist thoughts start to kick in.

12 light years is actually very close as interstellar distances go. Such a mission could probably be launched in our lifetimes if the whole world got together behind it (which they won't but still...)

From a practical standpoint though (assuming that every nation decided to work together) how would such a mission work?

We'd most likely need a generation ship, given that current estimates of max velocity is in the range of 0.5 to 0.8c.

That means spending trillions of dollars and putting thousands of people in a ship in orbit, sending them off and most likely never seeing them again.

But before that we'd want to send unmanned probes to:

a) test out the propulsion and other systems b) scout the planets themselves, identify a good candidate

But the probe itself would take 20-30 years to reach + 12 more to report back.

Otherwise you're asking thousands to be explorers and guinea pigs for all this technology, with no guarantees about finding a habitable planet or coming back home. With something like the Mars mission you'd probably get volunteers without any family. People would be far more reluctant if it's a generation ship.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#114

Post by batbomb »

EthanHeilman wrote: post #112
moonbug22 wrote: post #106

Earlier quoted context omitted.

You know about the SKA, right?

At first I thought you were making a joke about the human race prioritizing Ska[0] over new telescopes, but then I realized I wasn't on reddit and saw the "the". What is SKA? Super K? Aperture? [0]: https://en.wikipedia.org/wiki/Ska

square kilometer array

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#116

Post by ballade »

yohann305 wrote: post #108
kilroy123 wrote: post #100

I really really want project Starshot to become a reality. I think this is our best bet for scoping out these near by star systems. At least within our lifetime. If we could hit 50% speed of light we could do a fly-by mission in ~25 years. Then another 12 years waiting for the data. Honestly, ~37-40 years isn't bad for an interstellar mission. Remember the Voyager program has been going on for that long! So we alread…

I hope Elon Musk reads your inquiry

I would incredibly surprised if he hasn't already thought about similar things. I remember in an interview last year he stated that the Interplanetary Transport System SpaceX is building for whisking humans to mars and other celestial objects in the solar system will be tiny in comparison to the spaceships that humanity will build in the latter half of this century. Bear in mind, the ITS has more than 3x the lift-off thrust of the Saturn V, which is the largest rocket ever built.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#118

Post by BigChiefSmokem »

WednesdayThrow1 wrote: post #110
ExactoKnight wrote: post #101

I am flabbergasted that as a society we aren't rushing to build a 100 metre wide telescope mirror large enough for us to directly image the spectra of the potentially habitable exoplanets around us. A telescope this large could tell us whether any of these potentially habitable planets contain oxygen, and thus, biological processes. Yet thanks to funding cuts in science the biggest telescope we have in the pipeline r…

Maybe tech giants like Apple and Google should start using some capital to fund awesome ideas like this.

Unless they can explain to their shareholders what the benefit of that overwhelmingly long-term investment will be I don't see it happening. Maybe after SpaceX becomes a massively profitable company in the same vein as the tech giants, but not before.

Bill Gates also made it painfully clear that he wants his money to go to issues we can resolve right now here on Earth like renewable energy, clean water, fighting disease, etc, which is why philanthropists like him avoid funding anything space-related. They want to witness the fruits of their investments within their lifetimes.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#119

Post by kyberias »

chrismealy wrote: post #7

The fastest spacecraft ever built would take 4000 years to travel one light year.

But isn't it merely about fuel? I mean, in space you can just accelerate to most any speed significantly under light-speed just by running the engines. Right?

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#120

Post by outside1234 »

ExactoKnight wrote: post #101

I am flabbergasted that as a society we aren't rushing to build a 100 metre wide telescope mirror large enough for us to directly image the spectra of the potentially habitable exoplanets around us. A telescope this large could tell us whether any of these potentially habitable planets contain oxygen, and thus, biological processes. Yet thanks to funding cuts in science the biggest telescope we have in the pipeline r…

I thought I read that the state of the art is actually combining many smaller lense telescopes into a virtually larger mirrored one. Or did that fail in practice?
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