
Are we alone? Tiny spacecraft will head to Alpha Centauri to find out - ForHackernews
https://www.cnet.com/news/sending-tiny-spacecraft-to-alpha-centauri
======
robodale
It's "stories" like these I would read as a kid very early 80's, probably in
Popular Mechanics magazines or similar.

Depicted in these magazine articles and artist renditions: in the future
(certainly by the 2020s!), we will have bases on the Moon, maybe even Mars,
and rotating space stations... all the while wearing stylish futuristic
fashions (yet still looking very much 70's), the women sipping from glasses of
champagne and laughing to each other while in the background the men play some
yet-to-be-invented handball game.

~~~
dekhn
Hahah yes, for years I saw these pictures
([https://en.wikipedia.org/wiki/L5_Society](https://en.wikipedia.org/wiki/L5_Society))
and developed unrealistic expectations of human space exploration.

~~~
eganist
I don't know if they were unrealistic so much as they didn't anticipate the
cataclysmic demotivation that we as a planet incurred with the end of the cold
war.

~~~
ryandrake
Maybe they just vastly underestimated the cost of these things and
overestimated the return on investment. We _have_ the technology to build a
lot of sci-fi. It’s an economic problem, not a technical one. Even if moon
rocks were all made of solid gold it wouldn’t make economic sense to fly there
and pick them up.

~~~
Razengan
For a sentient civilization to be "successful" it has to be keep asking itself
the following questions:

\- What are we doing to ensure our survival?

\- What are we doing to ensure we propagate beyond our home?

\- What are we doing to ensure that, in the event of an unavoidable extinction
or apocalypse, the history of our existence and knowledge endures on?

So far we aren't doing any of that (although #3 may be accidentally taken care
of through our ruins.)

~~~
mjevans
We're sort of doing #3 with some stuff...

[https://news.ycombinator.com/item?id=11851871](https://news.ycombinator.com/item?id=11851871)

( archive.org link, because this article isn't online anymore. )

[https://web.archive.org/web/20180106124933/http://www.wipp.e...](https://web.archive.org/web/20180106124933/http://www.wipp.energy.gov/picsprog/articles/wipp%20exhibit%20message%20to%2012,000%20a_d.htm)

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bumholio
This century, it will not. We are very far from a technology capable of
achieving what Starshot proposes. Accelerating the spacecraft to a fraction of
the speed of light using a laser would require power densities that would
instantanously turn all known materials to plasma. The best mirrors and
coatings are many orders of magnitude too dark. The required laser and energy
bank would be, for all intents and purposes, a comics megaweapon capable of
blowing spacecrafts from orbit, or, with proper space reflectors, incinerate
enemy installations anywhere on the globe in seconds.

The craft would be completely unable to brake so it will pass past the target
planets in a matter of minutes. It's unclear what kind of sensors could be
employed to detect anything and we certainly lack the technology to beam and
receive back signals sent by a postage stamp craft 5 light years away. Let me
rephrase that: we haven't got even a theoretical model of a system that would
allow communication at such vast distances with milliwatt power sources.

Needless to say, nobody is seriously working on this, nor will they for many
decades at least.

~~~
Razengan
If the craft is packed with instructions on how to get back to us, maybe we
could get some sort of exchange going over multiple centuries.

On the other hand, if someone were to sent similar craft _to us_ , would we
even have a reasonable chance of detecting something that small without
knowing _exactly_ where, when and what to look for?

ʻOumuamua may have been a probe, yet even with our suspicions about it being
something out of the ordinary, we more-or-less collectively yawned and went
about our daily strife without making any effort to collect it.

[0]
[https://en.wikipedia.org/wiki/ʻOumuamua](https://en.wikipedia.org/wiki/ʻOumuamua)

~~~
madeuptempacct
I have been obsessing over Oumuamua as well, but there's just not that much
information, and we won't be getting more. Then there was the fact that it was
tumbling and wasn't emitting anything - one would expect radar scans or radio
transmissions, or at least something.

~~~
xj9
passive sensors are safer if you are sending probes into unknown territory
populated by potentially violent aliens.

~~~
java-man
violent aliens are much closer than you think ;-)

------
Razengan
There is no way that we are "alone" in a universe estimated to have
practically infinite planets.

However, the distances between stars and the very short windows of time in
which life may thrive (remember that we may have never known about the
dinosaurs on _our very own planet_ if we didn't discover their bones, and we
will never see them again) means that we may never meet any other life.

~~~
mihaifm
This is a very optimistic view, but there are plenty of theories claiming
otherwise. Check out the Fermi Paradox [1], or the Rare Earth Hypothesis [2]
for a more detailed view on the problem.

To be honest the easiest explanation for the Fermi Paradox is that we are
indeed alone as an inteligent civilization. If we were just an average
civilization there should be plenty of evidence of more advanced civilizations
across the galaxy, because probabilistically they would be millions of years
more advanced than us.

[1]
[https://en.wikipedia.org/wiki/Fermi_paradox](https://en.wikipedia.org/wiki/Fermi_paradox)
[2]
[https://en.wikipedia.org/wiki/Rare_Earth_hypothesis](https://en.wikipedia.org/wiki/Rare_Earth_hypothesis)

~~~
ChrisBland
To the single cell organism; the worm looks to be advanced and complex. To the
worm; the human looks to be advanced and complex. Its possible we are still
way down on the intelligence chain and too dumb to realize that we are in fact
the worm in the scope of the universe

~~~
Rattled
A cell has no way to conceive of a worm, and worms probably can't conceive of
humans. But they probably have some conception of birds, and birds can
perceive humans. Where are our birds? As you go up the intelligence chain the
ability to see beyond seems to increase, but we don't see anything beyond us.

~~~
sulam
We already have the concept of the eschaton, or the singularity. Is this a
realistic concept? I don't know! But if you accept it, then the inability to
see people at or beyond is is simple -- there is a large gap because progress
past the point we are at is geometric up to physical limits that we are
nowhere near today.

~~~
Rattled
I didn't have the concept of the eschaton until today, looks like an
interesting rabbit hole to explore.

~~~
DonHopkins
Congratulations on your recent immanentization of the concept of the eschaton!
;)

[https://en.wikipedia.org/wiki/Immanentize_the_eschaton](https://en.wikipedia.org/wiki/Immanentize_the_eschaton)

------
karimdag
Relevant (and quite enjoyable) read: The Three Body Problem (novel)
[https://www.amazon.com/Three-Body-Problem-Cixin-
Liu/dp/07653...](https://www.amazon.com/Three-Body-Problem-Cixin-
Liu/dp/0765382032)

~~~
madeuptempacct
This is the one book I have seen praised here endlessly. I am sincerely hoping
it can stand with Neal Stephenson's work. I don't think there is any other
author I can recommend unequivocally.

~~~
tralarpa
> hoping it can stand with Neal Stephenson's work

Thanks, always looking for new stuff to read. (edit: not really new, but new
to me :)

Concerning The Three-Body Problem, I found it a bit disappointing. Great build
up with a rather traditional solution making some things of the build up
looking a little bit silly.

~~~
lsadam0
I can understand why you say Three-Body has a rather traditional solution, but
I would argue said solution is misdirection. The first book is really just
setting up the real meat of the story, in the 2nd and 3rd books.

------
ChuckMcM
I always wonder about programs that require building a 100GW laser that can
target any point in the sky above it. While I"m sure there are many uses for
such a device, clearly one of them is disabling satellites. Which makes the
creation and operation of such a device destabilizing at a minimum and more
likely fairly provocative.

~~~
travisoneill1
Seems like overkill for shooting down satellites. IIRC the US and China have
already demonstrated this ability so I don't think it would add that much as a
weapon.

~~~
ChuckMcM
Don't under estimate the value of being able to shoot down a satellite with no
advance warning. Existing anti-sat weapons are typically launched from a
platform that is visible/trackable long before it can actually kill a
satellite.

~~~
travisoneill1
ICBM time to target is around 15 minutes. I assume that satellite shoot down
time is similar with a rocket. Does going from 15 minutes of warning to
instant give much of a tactical advantage?

~~~
ChuckMcM
Its the prep time. ICBM's have to be fueled or their silos opened or the
launchers positioned, etc. That can take hours. The F-15 antisat missile[1] is
pretty quick but the plane still has to get up to altitude and do a tricky
maneuver to launch it.

I am not a policy expert by any means, I just remember all the consternation
over systems which shorten the time between being ready and killing some
strategic asset.

[1]
[https://en.wikipedia.org/wiki/ASM-135_ASAT](https://en.wikipedia.org/wiki/ASM-135_ASAT)

------
mattferderer
This article introduces more questions than it answers to me.

How do you travel that fast & not disintegrate or crash into something?

Was Mr Manchester's experiment done using a laser to launch?

Has this been done before at any scale? Even pushing an item a few hundred
feet up?

Is there a timeline for this to even get attempted?

I think it sounds really awesome but that makes me wonder if any of this is
feasible soon. Sending tiny Raspberry Pi like devices into space at fast
speeds that could do cheap experiments more quickly, that would be nice.

~~~
neurobashing
Not to mention, where are all the other Bracewell probes from all the other
interstellar civilizations? If there's life shouldn't the local area be
teeming with them, since they're cheap and easy for any culture that can do
spaceflight? (also, for fans of The Expanse, something something
protomolecule)

~~~
snowwrestler
How the heck would we detect a 3 foot spacecraft that weighs a few grams,
passing anywhere through the Solar System at speeds over 10% of light?

We might be getting them once a week and we would have no idea. We can't even
find or track most of our own asteroids, and they're already in solar orbit.

------
ufmace
What I want to know is how they plan on steering these things. How do you get
a multi-gigawatt laser on Earth to not only hit a ping-pong ball sized thing
in space, but propel it in a particular direction, precisely enough that it
will pass through the inner solar system of a star system 4 light-years away?
Wouldn't an encounter with a tiny bit of gas or something near our solar
system cause it to be like a few billion miles off target?

~~~
mLuby
Recommend reading TFA:

>Think of it as a large pingpong ball with computers and cameras pointing in
different directions. The big advantage? The spherical shape, coupled with a
"hollow" laser beam that's stronger toward its outside edge, could be
naturally centered on the beam throughout the acceleration.

>"Imagine blowing a piece of paper straight up. It's going to fly off the beam
unless it's perfectly aligned," says Zac Manchester, a Stanford professor and
Starshot engineer who's researched the subject and already launched a 1.4-inch
square spacecraft into Earth's orbit.

~~~
istjohn
But also from TFA, the lasers will stop after the spacecraft travels about ten
times the distance between the Earth and moon. I think the question still
stands, is it possible to expect anywhere near the needed precision without
some kind of active steering over the four light years (minus ten moons) of
space that must be traversed? It certainly must be a limiting factor in the
utility of this scheme. I can't imagine using this tech to execute a planned
fly-by of an extra-solar moon, for example.

~~~
bumholio
10 times the distance to the Moon at an average speed of 0.1c takes about two
minutes. So you would launch thousands of these crafts in the general
direction of the target system and hope that at least one survives the
micrometeorite onslaught and passes close enough to the target planet to
snatch a few pictures. Or maybe even aero brake in the very thin heliosphere
or gas giant upper atmosphere and enter a highly elliptical Centauri-centric
orbit.

Or accidentally start an interstellar war.

------
tinnet
hope the space dust does not wipe off the writing on the front: "this is not a
laser powered bullet to destroy your planet, should totally just fly past, we
did the math"

~~~
lolc
Haha, any atmosphere at all would disintegrate those things. Earth sees that
calibre every minute. We'll totally aim right at the planets and won't hit
them anyway.

Edit: Well, I forgot the relativistic speed that ball would be traveling at.
So if the planet's inhabitants actually lived in the upper atmosphere some
might actually get burned.

------
HillaryBriss
Given that an approach like this could be implemented even on a lower power
basis, wouldn't we use it first for super fast, super frequent investigation
of planets and their moons _within_ the solar system? Isn't that the low
hanging fruit here?

------
HillaryBriss
This article has many insights I've never seen before.

This is my favorite: "If the dinosaurs had a giant laser, maybe they'd still
be here"

------
zamalek
I wonder if the laser could be used to clear space debris.

~~~
wlesieutre
Probably yes,
[https://en.wikipedia.org/wiki/Laser_broom](https://en.wikipedia.org/wiki/Laser_broom)

Finding and tracking very small/fast debris is a different matter, but if you
can find the debris and keep a laser aimed at it you can alter its orbit.

------
salutonmundo
"If the dinosaurs had a giant laser, maybe they’d still be here. - S. Pete
Worden"

aaaand it's going right in the quotes file.

~~~
georgeecollins
A giant laser might also have saved the Aztec civilization.

------
espinchi
Here's a bunch of startup ideas:
[http://breakthroughinitiatives.org/challenges/3](http://breakthroughinitiatives.org/challenges/3)

I'm mostly kidding. These are hard, hard problems, much better suited to
research organizations. Exciting stuff!

------
Grue3
If it's going to fly at such a large speed, what is the proposed mechanism to
stop it? This thing would instantly burn as soon as it reaches any planet's
atmosphere. Could Alpha Centauri's gravity field capture this spacecraft
somehow? Doesn't seem likely.

~~~
DowsingSpoon
I don't believe there is an intention to slow down or stop.

------
repler
I don't recall there being any exoplanets within the habitable zone at Alpha
Centauri.

------
lucb1e
TLDR for those who are already familiar with the idea and just want to know
the details: it'll travel at .2C, taking 20 years (4ly*.2), and there is no
launch date. It seems all still theoretical at this stage, though they're
pushing some serious funding. To report back they "hope" the spacecraft can
use lasers and we will "probably" hear a few when a bunch of them report their
measurements back.

------
S_A_P
I am curious as to how the radio tech will work for these things. Im skeptical
that something super low power will be able to send us back some pictures from
that distance? Is our current tech that good?

~~~
clarkmoody
It will use lasers to send the data. An interesting proposal to use the sail
as an antenna here:
[http://breakthroughinitiatives.org/forum/13?page=4](http://breakthroughinitiatives.org/forum/13?page=4)

------
pfdietz
If there is intelligent life on the star next door, the Fermi Paradox would
bite extremely hard. So, no, we're not going to find intelligent life there.

------
maxxxxx
Are they planning on sending signals back? Also how much observation can you
do with a little spacecraft that moves through a solar system at that speed?

~~~
darkstar999
Read the article to find out!

~~~
maxxxxx
I read it but it seemed very light on detail. How would they use the laser to
get a signal back?

~~~
antonvs
See "How will Breakthrough Starshot probes send their reports back to Earth?"
in the article at: [https://www.popsci.com/three-questions-for-breakthrough-
star...](https://www.popsci.com/three-questions-for-breakthrough-starshot)

~~~
maxxxxx
Sounds interesting but way out there. I wonder if they will prototype the
system with a flyby of an asteroid or similar to see if it even works shorter
distances.

------
SubiculumCode
It seems that while traveling that fast it would be hard to collect good data
from the system, but I am no physicist.

------
MichaelMoser123
i wonder how they deal with the possibility of collision - at this speed and
distance you will have a significant chance of bumping into something in
interstellar space. Also you will have to slow down the spacecraft somehow,
how would they go about it?

------
shmerl
What about using ion thrusters for such purpose?

------
Cheyana
[https://www.cnet.com/news/sending-tiny-spacecraft-to-
alpha-c...](https://www.cnet.com/news/sending-tiny-spacecraft-to-alpha-
centauri/)

------
DerekL
The link goes to an entirely different article.

~~~
ForHackernews
CNET has some kind of infinite scroll thing that messes with what "page"
you're actually on. I'm not sure if there's a better permalink?

------
throwaway456321
They're dreaming !

------
acqq
Also see:

"Is Humanity About To Accidentally Declare Interstellar War On Alien
Civilizations?"

[https://www.forbes.com/sites/startswithabang/2018/08/07/is-h...](https://www.forbes.com/sites/startswithabang/2018/08/07/is-
humanity-about-to-accidentally-declare-interstellar-war-on-alien-
civilizations)

"aiming to the level-of-precision needed to pass close to (but not collide
with) a target planet is virtually impossible. The “cone of uncertainty” for
any trajectory will include the planet we’re aiming for."

"A planet getting hit by a ~1 gram spacecraft moving at 60,000 km/s is going
to experience the same level of catastrophic effects as a planet getting hit
by a ~1 tonne asteroid moving at ~60 km/s, the equivalent of which happens on
Earth just once per decade. Each strike would hit their world with the same
energy that the Chelyabinsk meteorite struck Earth: the most energetic
collision of the decade."

~~~
lolc
I don't think a meteorite can be compared to such a tiny ball. The ball will
disintegrate when it's still 100km up. You get an intense flash. But I don't
think shock waves travel much up there.

