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Hawking, Zuckerberg, Yuri Milner announce plan to send micro robots to Alpha Centauri

Chemahkuu said:
None, it's a waste of yet more money.
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Nope not at all, even if there isn't a direct end result, the spurring of technological research has lots of other useful outcomes, or it could be used as a base point on another generation of probes in the future. As usual you are short-sighted and pointless.
 
Coco Pops 1967 said:
That's basically my idea too. I mean with all the probes that we do send out I am surprised no one has considered the idea of dotting relays all over our solar system to catch signals too weak to make it to Earth, boost them and send them home.
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One wonders how large current deep-space reception technology is, and how frequently repairs need to be made.
 
It would take centuries to get there, the signal would be too weak to detect beyond our solar system, and it would probably need hundreds of "relays" to boost it, goodluck launching something that massive, considering with all that additional mass, it would go several times slower, and take what? 2000 years to get there?

And if one fails, loses power, the craft goes a tiny fraction of one degree off course, it'll never get there or no signal again.
 
This site:
http://nextbigfuture.com/2016/04/billion-yuri-milner-is-spending-100.html
--makes the best points on the difficulties involved.

A quote:
If only we had a 100,000,000,000 W laser of course. And not any old laser, but one having substantially more power than any that has ever been built. HOW much more powerful? Perhaps we've forgotten about MIRACL (https://en.wikipedia.org/wiki/MIRACL), a 1,000,000 W continuous wave laser. Deuterium fluoride based. Destroyed itself on one of its runs. Somewhat too much power for it to handle. For 100,000,000,000 W, one only needs what, 100,000 of them? What am I whining about? Piece of cake! Black budget!

Yuri-- in case you are reading this--you are on the right track in terms of building very large structures--but you have the "Step 13 " Orbital - filled 10 km array" last.

I would submit you forget the lasers for now and go big first.

Solar sail and Space Solar Power Systems all require large structures in space to wortk. Why no be prepared to launch demonstrators with mixed uses.

As a rich man--you should work on the old pressure-fed booster concept known as Sea Dragon
https://en.wikipedia.org/wiki/Sea_Dragon_(rocket)

Right now, Russian space Rubles (a hard thing to come by) are going to Kazakhs--and out of the way launch pads.
But if you build Sea Dragon here: https://en.wikipedia.org/wiki/Sevmash
every Ruble that goes to space also goes into the pockets of Russian shipyard workers. This will allow for Russian Government support--so you don't go flat broke all on your own.

Sea Dragon uses shipyard tolerances and simple steels--and construction is more similar to a spar platform or water tower than an advanced airframe--like the AN-225, say

Trust me--the ability to place 500 tons of anything in orbit will be a boon to mankind--and help forward larger visions of the future.

Just having a huge dumb sail a few miles on the side (using existing mylars) can will be launchedl by Sea Dragon.

It won't be as fast as what you wan't--but it will get humanity back to thinking big again.
Вы устали от рублей собираются казахи ? Ну, тогда - поддержка Морской дракон
 
Even if the mission succeeded, there might not be anything worth exploring. There are no confirmed planets in the system. The only planet which was discovered might well turned out to be a "mathematical artifact of the window function used to create the time series for the original observations", to which the original discoverer conceded was probably the case.

https://en.wikipedia.org/wiki/Alpha_Centauri_Bb

Scientists have been unable to find any other planets in star systems that are less than 10 light years from us.
 
Didn't someone prove laser propulsion? I remember watching video of a small model of a ship, saucer shaped that had a laser under it and the laser beam itself was pushing it up off the launch cradle.

I'll try find it.

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I've attempted to estimate what will be necessary.

Here is my estimate of a laser-power lower limit from the acceleration of the chip spacecraft. 1 gram at 60,000 g's is 600 newtons of force. That's 600 (kg*m/s) / s

Since that momentum comes from light, we multiply by c to get the light's energy rate. It's 1.8*10^11 watts. Taking into account reflection gives 10^11 watts, what someone else had calculated. By comparison, the US's electricity consumption is about 4.7*10^11 watts. So this system will require an energy flux of well into the terawatts (10^12 watts), if not a lot more. So one would likely require much more than humanity's current technological energy consumption.


Let's see what distance the chip ships will accelerate over. The target speed of 20% c is about 60,000 km/s. or 6*10^7 m/s. The acceleration is 6*10^5 m/s^2. The ratio gives a time of 100 seconds and a distance of 3*10^9 m.

With a 1-m sail, that means an angular size of 3*10^(-10). Either one aims extremely precisely, or else one uses much more energy that one needs in a beam much broader than the sail's apparent size.


Communicating results back home will be *very* difficult. The Sun's luminosity is 3.9*10^(26) watts, and the three Alpha Centauri stars have luminosities 1.519, 0.5002, and 0.0017 times the Sun's. So I'll use the Sun as a reference, since it's a good approximation for the first two.

Let's see how much a chip ship would get from one of these stars. The Sun at 1 AU emits 1361 watts/m^2. A centimeter-sized chip would receive only 0.1361 watts, an inch-sized one 0.88 watts, and a hand-sized one 13.61 watts (a hand for measuring horse heights is 10 cm or 1 decimeter).

So let's say it emits 1 watt. With a size of 1 hand (10 cm), it could focus the light to within 10^(-5) radians, about 2 seconds of arc. That means an equivalent isotropic radiated power (EIRP) of about 10^10 watts.

Using a spectroscope can cut away most of the light. The best ones go down to about 1 m/s, or 3*10^(-9). That means that the Sun emits about 1.2*10^18 watts in that band. So the chip ships will be outshone even in a best-case scenario.

The chip ships could use radio, but to get good focusing, one needs a very big antenna.
 
The biggest problem with humanity is it's lack of foresight. Often, it puts money into human-centric, fleeting projects that aren't useful down the line. I recall many of us space-aficionados decrying the short-sightedness in the 80s and 90s. With the emergence of the techno-philanthropist of late, we now have a handful of people who are looking beyond the navel-gazing politicians and narrow visions and backing projects with money.

I don't know when any of the plans for solar-satellite, asteroid mining, or the handful of interstellar flight plans will come to fruition, I only know we won't have any of them 50-100 years from now if we don't start now.

RAMA
 
Coco Pops 1967 said:
Didn't someone prove laser propulsion?
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You are thinking of: Leik N. Myrabo
http://www.cgpublishing.com/Author_Bios/leik_myrabo.html
http://www.cgpublishing.com/Books/lightcraft.html

APOGEE PRESS new home--at CG

Johndale Solem’s ‘Medusa,’ was to be "a combination of sail technologies with nuclear pulse propulsion."

http://www.centauri-dreams.org/?p=23754

No lasers needed--just nukes.

One can visualize the motion of this spacecraft by comparing it to a jellyfish. The repeated explosions will cause the canopy to pulsate, ripple, and throb. The tethers will be stretching and relaxing. The concept needed a name: its dynamics suggested Medusa.

New book on future drives
http://www.amazon.com/gp/product/15...2&tag=centadream0b-20&linkId=53DWEYK73VWZ7BEY

The odds of Starshot
http://www.centauri-dreams.org/?p=35412

Some seem to think small plates are not the way to go.

Bubble sails interest me. If you combine bubbles in a certain way--you can get a flat plane
http://nextbigfuture.com/2007/04/possibly-last-niac-studies-are-being.html

More surface area means easier aiming for lasers--less burn through.

I vote for the brute force approach
http://nextbigfuture.com/2014/10/brute-force-terraforming-of-mars-moons.html

HLLVs that are ever larger--proper gov't funding, etc.

Space settlement will be TVA not MSN
 
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Spending money on necessary things that people need right now is not "short sightedness". Wasting money on a probe that needs about five major breakthroughs to leave the solar system, to do something centuries from now is exactly the kind of thing that should not be done, when people need that money to you know, not starve or die.
 
That's why this needs to be combined with space-based solar power--to reduce CO2.

This doesn't have to be either/or.

Ground based solar won't help exploration--or deflect asteroidfs.
Larger and larger structures in space--that is a rising tide to lift all boats.
 
Which is not what this probe is about, keeping things in-system and even orbital sounds a lot more worthy of investment than the OP proposal.
 
Chemahkuu said:
Spending money on necessary things that people need right now is not "short sightedness". Wasting money on a probe that needs about five major breakthroughs to leave the solar system, to do something centuries from now is exactly the kind of thing that should not be done, when people need that money to you know, not starve or die.
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False dichotomy. You make it sound like spending money in space = people starve. That is a bold claim and I would love to see if you have any evidence at all to back it.
 
publiusr said:
That's why this needs to be combined with space-based solar power--to reduce CO2.

This doesn't have to be either/or.
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Truly, the best way to advance the cause of an unbuilt space-probe technology which seems to require several major significant breakthroughs to work is indeed to tie it to an unbuilt space-power technology which seems to require several major significant breakthroughs to work. Win-win!
 
Coco Pops 1967 said:
IN the old days that was called "trial and error" we build stuff and see if it works, and if it doesn't we tweak it till it does.
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The problem being here, that the probe will be outside the solar system, it'll be hard to even know what went wrong to do differently next time.
 
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