NASA Relativistic Interstellar Laser Launcher: We could do it NOW, for the cost of the NASA Climate Budget

Figure 9 from "A Roadmap to Interstellar Flight"
Figure 9 from “A Roadmap to Interstellar Flight”

Guest essay by Eric Worrall

An American scientist has made a remarkable conceptual breakthrough, a design for a non nuclear relativistic launcher, capable of accelerating thousands of deep space probes per year to 0.25C; fast enough to reach the nearest stars in 15 years. The system is extremely scalable – you could start with a small, low cost proof of concept launcher, and work up to bigger devices, capable of launching substantial probes into interstellar space. The system also has a practical alternative use – the full size version is powerful enough to deflect dangerous asteroids into safer orbits. The design uses mostly off the shelf industrial laser and optical technology.

The abstract of the study;

In the nearly 60 years of spaceflight we have accomplished wonderful feats of exploration and shown the incredible spirit of the human drive to explore and understand our universe. Yet in those 60 years we have barely left our solar system with the Voyager 1 spacecraft launched in 1977 finally leaving the solar system after 37 years of flight at a speed of 17 km/s or less than 0.006% the speed of light. As remarkable as this we will never reach even the nearest stars with our current propulsion technology in even 10 millennium. We have to radically rethink our strategy or give up our dreams of reaching the stars, or wait for technology that does not exist. While we all dream of human spaceflight to the stars in a way romanticized in books and movies, it is not within our power to do so, nor it is clear that this is the path we should choose. We posit a technological path forward, that while not simple, it is within our technological reach. We propose a roadmap to a program that will lead to sending relativistic probes to the nearest stars and will open up a vast array of possibilities of flight both within our solar system and far beyond. Spacecraft from gram level complete spacecraft on a wafer (“wafersats”) that reach more than 1⁄4 c and reach the nearest star in 15 years to spacecraft with masses more than 105 kg (100 tons) that can reach speeds of greater than 1000 km/s. These systems can be propelled to speeds currently unimaginable with existing propulsion technologies. To do so requires a fundamental change in our thinking of both propulsion and in many cases what a spacecraft is. In addition to larger spacecraft, some capable of transporting humans, we consider functional spacecraft on a wafer, including integrated optical communications, optical systems and sensors combined with directed energy propulsion. Since “at home” the costs can be amortized over a very large number of missions. I n addition the same photon driver can be used for planetary defense, beamed energy for distant spacecraft as well as sending power back to Earth as needed, stand-off composition analysis, long range laser communications, SETI searches and even terra forming. The human factor of exploring the nearest stars and exo-planets would be a profound voyage for humanity, one whose non-scientific implications would be enormous. It is time to begin this inevitable journey beyond our home.

Read more: http://www.deepspace.ucsb.edu/wp-content/uploads/2015/04/A-Roadmap-to-Interstellar-Flight-15-h.pdf

NASA spends around a billion dollars per year on GIS climate research. The GIS budget was reviewed in 2011, on the grounds that they are duplicating work done by NOAA/NCDC, but the GIS budget survived the review.

A billion dollars per year would go a long way towards funding a pilot laser launcher program. Given the linear scalability of the proposed system, ongoing funding of this magnitude would allow progressive scaling of the prototype into a full size launcher.

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CodeTech
March 27, 2016 10:22 pm

105 kg (100 tons) ?

Reply to  CodeTech
March 27, 2016 10:48 pm

If you read the pdf it shows up as 10^5 kg, which is precisely 100 metric tons.

GoatGuy
Reply to  Kevin Roberts
March 28, 2016 6:32 am

Which is what inevitably happens when 10[sup]5[/sup] loses its [sup] tags. Even 10^5 should look like 10⁵

Alastair Brickell
March 27, 2016 10:27 pm

We certainly need a new vision to get our space exploration moving ahead again and this idea has some merit…not without lots of problems though. How can these probes be slowed down at the other end to be able to go into orbit or land rather than just zipping though a solar system in a few hours after all that travel time?

jimheath
Reply to  Alastair Brickell
March 27, 2016 10:35 pm

Hail the driver.

george e. smith
Reply to  jimheath
March 28, 2016 9:19 am

I noticed immediately this adjective: …… mostly …..
Adjectives turn the ho-hum into the spectacular achievement.
Give us a shout when ALL of these technologies are available ON the shelf.
G
But while I’m not doing much of anything, I’ll get right on this project; after flipping the on switch of ITER !

Unmentionable
Reply to  Alastair Brickell
March 27, 2016 10:44 pm

Yes, that’s what I was thinking, you could deflect it on to another nearby star I suppose.
Could cause a diplomatic incident if there were something that took a dim view of unannounced relativistic ‘spy’ missiles flying by. Could be something of a misconstrued noob error.

billw1984
Reply to  Unmentionable
March 28, 2016 4:22 am

Just what I thought. Send near light speed 100 ton objects hurtling into nearby star/planetary systems with no brakes.

DC Cowboy
Editor
Reply to  Unmentionable
March 28, 2016 4:51 am

Could spark an interstellar war if one of them happened to slam into a habitable planet — by accident. I know we’d take a dim view if 100 metric ton objects started taking out small sized cities

hanelyp
Reply to  Unmentionable
March 28, 2016 2:32 pm

If there was a civilization orbiting the target star they’d know something was up several years before a probe arrived.

Marcus
Reply to  Alastair Brickell
March 27, 2016 11:11 pm

…Toss out the anchor ???

Reply to  Alastair Brickell
March 28, 2016 8:24 am
george e. smith
Reply to  sunshinehours1
March 28, 2016 9:21 am

Gravity sucks; NO braking aloud !

tommoriarty
March 27, 2016 10:43 pm

“105 kg (100 tons)” Huh?

GoatGuy
Reply to  tommoriarty
March 28, 2016 6:34 am

10^5 = 10⁵ kg = 100,000 kg ≡ 100 MT

March 27, 2016 10:45 pm

Not that the whole of NASA’s “climate budget” wouldn’t be even more beneficially treated were it left in the pockets of the private citizens – the productive sector of our society – from whom it’s presently being mulcted.

Giving money and power to government is like giving whiskey and car keys to teenage boys.

— P.J. O’Rouke, Parliament of Whores (1991)

Autochthony
Reply to  Tucci78
March 28, 2016 12:55 pm

Tucci
+ loads.
A simple – yet accurate – exposition.
Auto

March 27, 2016 10:46 pm

The paper has 3 citations, all from the same author.
It says Submitted to JBIS, which I assume is the Journal of the British Interplanetary Society, but I haven’t been able to find out if it ever passed peer-review to be able to be published.
Skimming through the paper, I see quite a few hyperbolic phrases, but I don’t have the physics background to be able to parse the content. Still, all signs point to this being a waste of time, and it’s no good to just replace funding to one area of bad science with another.

Reply to  Kevin Roberts
March 28, 2016 12:12 am

It was probably an april fools joke For a sceptic, eric is sure gullible

Reply to  Steven Mosher
March 28, 2016 1:44 am

Pretty elaborate joke if that is what it is. Here’s a video.
https://www.facebook.com/FollowNASA360/videos/10156484765630285
The idea of directed energy propulsion has been around for a long time. I don’t know whether this paper breaks any new ground.

GoatGuy
Reply to  Steven Mosher
March 28, 2016 6:36 am

James Cross asks (rightly), I don’t know if it breaks new ground.
It does not.
This is a modern “hope and change” or “reach for the stars” articles. Pure compressed helium.
GoatGuy

Reply to  Steven Mosher
March 28, 2016 8:29 am
BFL
Reply to  Steven Mosher
March 28, 2016 8:56 am

Wouldn’t a laser with kind of power (100MT) burn right through the receiver (unless using ablative materials for propulsion which is not apparent in the drawing), and then there is the matter of powering the laser itself. There is also the focusing requirements at long range which would be difficult even for a laser. For once I agree with Steve.

Reply to  Steven Mosher
March 28, 2016 11:44 am

No, it’s serious – there are quite a few teams around the world working on similar concepts, including some really tiny ones, with each probe weighing just a few grams.

BFL
Reply to  Steven Mosher
March 28, 2016 3:57 pm

“there are quite a few teams around the world working on similar concepts,”
Well if the money flow works for climastrology, then why not?

john harmsworth
Reply to  Kevin Roberts
March 28, 2016 12:32 pm

I thought Mike Mann got a Nobel for this already!

Dodgy geezer
March 27, 2016 10:49 pm

That’s nothing!
The Brits have got a complete single stage to launch space plane, ready designed, and proven to work. Total cost of development – 12bn, which is peanuts. They spend this money on abortive CCS projects…..

LarryD
March 27, 2016 10:51 pm

“… but the GIS budget survived the review.”
Of course it did. Call me cynical, but I believe the point is graft, not research.

Unmentionable
March 27, 2016 11:09 pm

Page 6: “… this technology is NOT science fiction. Things have changed. The deployment is complex and much remains to be done but it is time to begin. Since the system is modular and scalable the costs to begin are very modest as even small systems are useful. The same system can be used for many other applications as outlined in our papers which amortizes the costs over multiple tasks. … ”
Ambitious but I’m wondering why they are not proposing a solar system scale transportation mechanism first? For we have proven we can build reliable electronics that lasts many decades in space, so we can pre place decelerator lasers around the solar system, at each planet and moon of interest, and ping-pong materials stuff around the solar system quickly. Walk before run?
Or do they want long range probes, as well, in parallel to doing that? If not science fiction, but doable, this is a pretty interesting approach.

Marcus
Reply to  Unmentionable
March 27, 2016 11:23 pm

..It is only good for 105 kgs..I think ??

Unmentionable
Reply to  Marcus
March 27, 2016 11:47 pm

No, it’s actually 100 tons.
If the distances are shorter, solar system scale, it may be possible to accelerate a much larger load to slower, more manageable interplanetary speeds. Depends how long it takes to accelerate and decelerate it. There would be a happy medium somewhere between weight and speed of transit, against cost and requirement.

Unmentionable
Reply to  Unmentionable
March 28, 2016 12:15 am

Ah, there it is, as currently envisioned, it has a single use sail.
“… Laser Sail. The laser sail is both similar to and fundamentally different than a solar sail. For small sails, even with low powers the flux can easily exceed 100 MW/m2 or 105 Suns. This requires a very different approach to the sail design. Fortunately the laser line is very narrow so we can tune the laser sail reflectivity to be extremely high and the absorption to be extremely low using multi layer dielectric coatings. The relativistic aspects of the highest speed missions present another problem as the laser wavelength is shifted at the reflector. Laser coatings on glass already can achieve 99.999% reflectivity or absorption of less than 10-5. We have started working with industrial partners and have designed a “roll to roll” process that is a multi-layer dielectric on plastic that achieves 99.995% reflectivity (in design). …”

GoatGuy
Reply to  Unmentionable
March 28, 2016 6:38 am

10⁵ suns, absorption < 10⁻⁵ …

Unmentionable
Reply to  Unmentionable
March 28, 2016 8:48 am

The complication is the drop in frequency as it accelerates away. The absorption of the sail has to maintain that low absorption at all intervening frequencies. If they’re using coatings this implies each coating is going to be burned off to reveal the next low-absorption coating or membrane for that new lower frequency.
Thus rendering the sail a single-use item. And meaning you can’t use it for deceleration either, within the solar system, as the deceleration will occur first at a higher frequency as the sail approaches.
However, in the solar system context the velocities involved would be much lower, so frequency shifts lower than at interstellar speed. So not impossible to make a sail that could work for both acceleration and deceleration.

Michael J. Dunn
Reply to  Unmentionable
March 28, 2016 12:52 pm

That’s 10,000 watts/sq.cm. In the laser weapon business, it was typical to specify an “open fire” threshold no lower than 100 watts/sq.cm. What about high reflectivity? We regarded that as merely a theoretical possibility, not an operational one. In the real world, random accumulations of “stuff” would be enough to reduce the reflectivity, even if only as a speck. The equilibrium radiant flux of molten titanium is on the order of a few tens of watts per square centimeter, so we took it for granted that the inevitable imperfections would result in surface blemishes that would grow and deteriorate the rest of surface.
Also, what total power level are we talking about? I presume any such sail might be 1 km2 in extent, which would imply a laser projecting 100 trillion watts. Even 100 million watts is a pipe dream. Any such system would be, de facto, an anti-satellite weapon par excellence. It could probably be used to write imperishable graffiti on the face of the moon! (Maybe even on Mars.) I won’t stay up late nights in expectation…

oeman50
Reply to  Unmentionable
March 28, 2016 9:42 am

Has anyone read, “The Mote in God’s Eye,” by Niven and Pournelle?

john harmsworth
Reply to  oeman50
March 28, 2016 12:56 pm

Yes, one of my all time favourites!

March 27, 2016 11:39 pm

America could do a whole lot of useful and worthwhile things if the government was not obsessed with wasting money on ‘Climate Change / Global warming / CAGW. One of them could be the NASA Relativistic Interstellar Laser Launcher:

March 27, 2016 11:51 pm

NASA Marc Millis talk on interstellar space travel….
https://youtu.be/9doOLHeW8p4?list=PLP52dI6_8CQIWy87oJwSUtwg6hMSDJSSC

Reply to  Ben D
March 28, 2016 2:02 am

here are some other projects, worked on, including his at NASA
http://www.bbc.co.uk/news/magazine-35861334

Dudley Horscroft
March 27, 2016 11:52 pm

Kevin Roberts March 27, 2016 at 10:48 pm said “If you read the pdf it shows up as 10^5 kg, which is precisely 100 metric tons.”
Thank you Kevin, but what a pity. It reminded me of the old saying “2 plus 2 = 5 for sufficiently large values of 2”
According to Wikipaedia:
Orwell’s protagonist, Winston Smith, uses the phrase to wonder if the State might declare “two plus two equals five” as a fact; he ponders whether, if everybody believes it, does that make it true? The Inner Party interrogator of thought-criminals, O’Brien, says of the mathematically false statement that control over physical reality is unimportant; so long as one controls one’s own perceptions to what the Party wills, then any corporeal act is possible, in accordance with the principles of doublethink (“Sometimes they are five. Sometimes they are three. Sometimes they are all of them at once”)
Reminds me of CAGW.

Robert
Reply to  Dudley Horscroft
March 27, 2016 11:58 pm

What a stupid idea , why would NASA want to waste money on space exploration or any space related matter when they can gouge the money and just use a crystal ball for doing earth research . Priorities please !

Reply to  Dudley Horscroft
March 28, 2016 10:01 pm

“Sometimes they are five. Sometimes they are three. Sometimes they are all of them at once”

Hmm. I had no idea Orwell was a quantum physicist.

Scottish Sceptic
March 28, 2016 1:24 am

Like almost every thing NASA does, from climate to Mars, it serves absolutely no purpose except to create work for NASA

Reply to  Scottish Sceptic
March 28, 2016 4:07 am

100 % agree.

ozspeaksup
Reply to  Scottish Sceptic
March 28, 2016 4:46 am

err a no tech in that area Q…
HOW??? do they plan to power this setup?
surely its going to require some massive power supply to get tons of stuff thrown up to space?
replace fuel in rockets to???? power to run a laser

D. J. Hawkins
Reply to  ozspeaksup
March 28, 2016 8:36 am

Never heard of solar cells? And you probably don’t need a whole lot to boost a few wafersats as proof of concept.

exSSNcrew
Reply to  ozspeaksup
March 29, 2016 9:40 am

Power doesn’t come spontaneously from the wall socket? Who knew!?!?

Gary Pearse
Reply to  Scottish Sceptic
March 28, 2016 9:56 am

Like Columbus setting sail, a complete waste of money and time on exploration. The Wright brothers aircraft is another example of expensive useless ventures. We were very happy with a flat earth and some of us wish we could go back to it.

Glenn999
Reply to  Scottish Sceptic
March 28, 2016 5:25 pm

Scottish Sceptic
What would you like to see NASA doing?

exSSNcrew
Reply to  Glenn999
March 29, 2016 9:46 am

Empower private commercialization by providing the R&D and documentation support for legislation. The more opportunities for people to make money  the more rapidly space becomes viable venue for humans. Rather than create the lift vehicles and infrastructure via NASA, help the private sector take on those roles.

March 28, 2016 1:26 am

I like it. Will it work? I don’t know. At least someone one is thinking, proposing and exploring.
That to me is a step forward. Without that we’d be stuck.
I like the idea!

john harmsworth
Reply to  asybot
March 28, 2016 2:28 pm

Amazon announces plans to fire packages at peoples homes at .25C with no method for stopping them! Asking for volunteer recipients.

March 28, 2016 1:38 am

So which politicians would we elect to go on the first manned one?
I can think of quite a few ………. .

prjindigo
March 28, 2016 1:50 am

We need to get on this NOW so we’ll be ready for the Kzinti when they show up!

JohnB
Reply to  prjindigo
March 28, 2016 7:08 am

“A reaction drive’s efficiency as a weapon is in direct proportion to its efficiency as a drive.”

Analitik
March 28, 2016 2:17 am

So we’re the Moties?

Reply to  Analitik
March 28, 2016 4:55 am

Indeed! Seems we’re going full ‘Crazy Eddie’.

Reply to  Analitik
March 28, 2016 7:30 am

Analitik asks:

So we’re the Moties?

Our more technologically advanced cultures seem to be suffering reduced fecundity, though it’s true that the cultures dominated by a 7th-Century barbarity (and therefore incapable of the sustained scientific advancement needed for high-tech civilization) are showing high birth rates, whereas on the gripping hand dar al-Islam sanctions such a high degree of consanguinity in their marriages that they’re manifestly breeding for imbecility….

oeman50
Reply to  Analitik
March 28, 2016 9:43 am

Oops, answers to an earlier post about “The Mote in Gods’ Eye.”

Reply to  oeman50
March 28, 2016 10:08 am

oeman50 writes about

…answers to an earlier post about “The Mote in Gods’ Eye.”

…with regard to us being the Moties, and apparently I have to clarify my response.
In Pournelle & Niven’s The Mote in God’s Eye (1974), the writers posited that the Motie civilization was biologically destined for cycles of catastrophic war because of a drive to reproduce that’s literally a matter of life or death for each individual, resulting in horrendous population pressures, and that the “natural selection” thereby imposed had resulted in advancing (specialized) intelligence and ferocity in the species.
With regard to H. sapiens terra, however, what we’re apparently seeing is that the more technologically advanced one of our societies becomes, the lower the prevailing reproduction rates. This observation seems to justify C.M. Kornbluth’s premise in “The Marching Morons” (1951; plagiarized most prominently as the premise behind 2006’s Idiocracy) that as human technological and economic advances continue, we’re breeding against intelligence.
As dar al-Islam is definitely breeding for Abdul Kallikak and Mohammed Jukes imbecility.

March 28, 2016 2:43 am

God another NASA money black hole.
NASA cant get satellites into low orbit without blowing up rockets, are currently too concerned to send manned flights through the VB and depend on Russia for rocket tech for missions.
Can we come back to reality, this is a concept, based off of a theory. While interesting to explore, beware of concepts, reality tends to leave the room.
The technological reality is this is currently dreaming, interesting as it is, nothing more.

A C Osborn
Reply to  Mark
March 28, 2016 4:20 am

It was not that many years ago that automobiles were dreaming, flight was dreaming, space flight was dreaming, Computers were dreaming, Phones that are portable, take photos and connect to the internet were dreaming Atomic Energy was dreaming, most modern medicine was dreaming.
That is what Science, Engineering and Mankind’s advance is made of, your negative attitude stinks.
What is required is Application, another space race, or leave it to the current batch of entrepreneurs who are adding to our advancement.

Reply to  A C Osborn
March 28, 2016 7:59 am

Exactly right. Ad astra per aspera.
/Mr Lynn

D. J. Hawkins
Reply to  A C Osborn
March 28, 2016 8:46 am

@L.E. Joiner
The motto of my Alma Mater.

Reply to  A C Osborn
March 28, 2016 9:04 am

Latin is a DEAD language.
Why not use Klingon sayings.
Oh, then you would not be so erudite.

Bob Boder
Reply to  A C Osborn
March 28, 2016 9:31 am

Do you realize there was less time between Lindbergh crossing the Atlantic and the Moon landings then between now and the Moon landings. Is technology really progressing or have we lost all ability to do things for ourselves? Image for a second what the people at NASA 50 years ago could do with all the new systems and materials we have today, yet we can’t even match what they could then.

Reply to  A C Osborn
March 28, 2016 8:14 pm

@ Rob Roy: Not intending (or imitating) erudition.
Ad Astra is the name of the National Space Society’s magazine.
Also:comment image
/Mr Lynn

Reply to  L. E. Joiner
March 29, 2016 2:30 am

In a tower of flame in Capsule Twelve, I was there.
I know not where they laid my bones; it could be anywhere.
But when fire and smoke had faded, the darkness left my sight,
And I found my soul in a spaceship’s soul riding home on a trail of light.
And my wings are made of tungsten,
My flesh of glass and steel.
I am the joy of Terra for the power that I wield.
Once upon a lifetime,
I died a pioneer;
Now I sing within a spaceship’s heart
Does anybody hear?

— Julia Ecklar, “The Phoenix” (1983)

Reply to  A C Osborn
March 29, 2016 6:32 am

@Tucci78 March 29, 2016 at 2:30 am
Nice writing. I found a YouTube video of the song here:

/Mr Lynn

Reply to  L. E. Joiner
March 29, 2016 12:32 pm

Regarding Julia Ecklar’s filksong “The Phoenix” it might be remembered that the fire which killed Grissom, White, and Chaffee (as well as the Challenger and Columbia disasters) had arguably instantiated the bureaucratic imperative at NASA in action.
Track down a copy of Victor Koman’s Kings of the High Frontier (1998) for a speculative examination of the cogent argument that NASA is principally the vehicle by which the governing class (our enemies foreign and domestic) is preventing private-sector exploitation of “the High Frontier.”

Robert of Ottawa
March 28, 2016 4:21 am

1. Billions of dollars a year will enable us to develop ANY rocketry system.
2. Laser impelled rockets are not new.
3. A lot of work needs to be done to create sensor systems that will gather information in the 1 hour it passes through the solar systems it encounters.
4. If the Keunesians cannot resist spending invented government money, then buying rocketry seems like the least bad way to do it.

D. J. Hawkins
Reply to  Robert of Ottawa
March 28, 2016 8:54 am

At 0.25C, it’s going to take a lot longer than an hour to pass through a solar system the size even of our own. At that speed, Mars is about an hour away from Earth, depending on orbital position. The width of our solar system at light speed is 8 hours, plus or minus, based on the orbital path of the farthest planet.

Gamecock
March 28, 2016 4:44 am

What if the Centaurians back engineer it and come to get us ?!?!

Tom in Florida
March 28, 2016 4:59 am

The problem with such speeds is how do you stop. Let’s take a trip to the Moon. It only takes 10 hours from Earth orbit. (distance approx 250,000 miles at 25,000 mph). In order to slow down enough to enter lunar orbit you must carry the fuel to do so. That means at launch you have a heavier payload so you need a bigger rocket and more fuel to launch but then you have to calculate how much more fuel you need to launch the extra fuel but then you have to calculate THAT extra fuel and so on. Eventually you break even but for the Apollo missions it was easier and less expensive to let Earth’s gravity do the slowing work so that the spacecraft had to carry a only a small amount of braking fuel.

Michael J. Dunn
Reply to  Tom in Florida
March 28, 2016 12:55 pm

Oh, yes. What is the density of interstellar matter? And what happens when a dust mote at 0.25 of the speed of light impacts the spacecraft? Not to mention a baseball. We keep thinking space really has nothing in it…excepting all the stuff that actually shows up.

Glenn999
Reply to  Michael J. Dunn
March 28, 2016 5:27 pm

obviously shield technology will have to be greatly advanced

March 28, 2016 5:17 am

The paper made the claim of reaching mars orbit in 30 minutes. At 57.6 million km a trip of 30 minutes would require acceleration of about 3,600 g’s. Wouldn’t that be enough to squash a steel ball-bearing into a pancake?

GoatGuy
Reply to  Randy Bork
March 28, 2016 6:44 am

No (stainless steel pancake). Well, not quite ‘no’ – because it depends on the size of the bearing. Volume goes up per D³ (D = dimension), so must also a solid sphere’s mass. Surface area however only goes up per D², so rises more slowly. At sufficiently large D, the force exerted by D³ overcomes the strength of the material covering D², and it deforms. But still the answer is “no” for ball bearings one might buy at the hardware store. GoatGuy

Reply to  Randy Bork
March 28, 2016 10:34 am

Lets try something a bit more modest, accelerate comfortably at 1g (10m/s^2) and do so for ~1 day (100,000 secs).
At the end of the day you’ll be traveling at 1,000,000 m/s (1,000 km/s), and will have travelled 100,000 km, well past Mars.

john harmsworth
Reply to  Phil.
March 28, 2016 3:23 pm

For human travel, this is the way to go. Accelerate at 1G or a shade more to half way or a shade more and then decelerate at 1 G to destination. A little harder ( 1.5G?) would be ok for a few days on the way out and on the last few days at arrival. The only way to travel.

Reply to  Phil.
March 28, 2016 6:55 pm

Should be 100,000,000km.

Joseph Shaw
Reply to  Randy Bork
March 28, 2016 7:19 pm

Not really. 3600g is within the range of accelerations experienced by projectiles fired from current artillery systems. We already have projectiles with electronic fuses, GPS guidance, and flight controls that survive these accelerations, Railgun systems with significantly higher accelerations are already in development.

Leonard Weinstein
March 28, 2016 5:40 am

The idea of using laser driven space travel (using a stationary laser beamed against a vehicle with collector sail) has been around for many years. At least two science fiction books used the concept and had enough technical details to show the practical possibility. If the author claims this is his idea, he is a plagiarizer.

Tom Halla
March 28, 2016 5:43 am

As an old science fiction fan, why not laser launchers to orbit, c.f. Pournelle in the 1970’s. I lack the hard science backround to judge, but Pournelle was not noted for making things up he considered implausible. However, we will not get anything of the sort without a major change in government, including the current management at NASA..

Philip Mulholland
Reply to  Tom Halla
March 28, 2016 1:24 pm

Not necessarily implausible, perhaps just very improbable:-

The Infinite Improbability Drive is a wonderful new method of crossing interstellar distances in a few seconds, without all that tedious mucking about in hyperspace. The principle of generating small amounts of finite probability by simply hooking the logic circuits of a Bambleweeny Fifty-Seven Sub-Meson Brain to an atomic vector plotter suspended in a strong Brownian Motion producer – say a nice hot cup of tea – were, of course, well understood. And such generators were often used to break the ice at parties, by making all the molecules in the hostess’s undergarments simultaneously leap one foot to the left, in accordance with the Theory of Indeterminacy.
Many respectable physicists said that they weren’t going to stand for that sort of thing, partly because it was a debasement of science, but mostly because they didn’t get invited to those sorts of parties. Another thing they couldn’t stand was the perpetual failure they encountered in trying to construct a machine that could generate the infinite improbability field needed to flip a spaceship between the furthest stars. And in the end they grumpily announced that such a machine was virtually impossible.
Then, one day, a student, who had been left to sweep up the lab after a particularly unsuccessful party, found himself reasoning this way: “If such a machine is a virtual impossibility, then, it must logically be a finite improbability! So, all I have to do in order to make one, is to work out exactly how improbable it is, then feed that figure into the finite improbability generator, give it a fresh cup of really hot tea… and then turn it on.” He did this and was rather startled to discover that he managed to create the long-sought-after Infinite Improbability Generator out of thin air.
It startled him even more when, just after he was awarded the Galactic Institute’s Prize for Extreme Cleverness, he got lynched by a rampaging mob of respectable physicists who had finally realised that the one thing they really couldn’t stand was a smart-arse.

Infinite Improbability Drive

Scene 6. Int. Heart of Gold

FORD: I think this ship is brand new, Arthur.
ARTHUR: How can you tell? Have you got some exotic device for measuring the age of metal?
FORD: No, I just found this sales brochure lying on the floor. “The Universe can be yours.” Ah, and look, I was right, “Sensational new breakthrough in improbability physics. As the ship’s drive reaches infinite improbability, it passes through every conceivable point in every conceivable universe almost simultaneously. You select your own re-entry point. Be the envy of other major governments.” This is big-league stuff.
ARTHUR: It looks a hell of a lot better than that dingy Vogon ship. This is my idea of a spaceship! All gleaming white, flashing lights, everything. What happens if I press this button?
FORD: I wouldn’t…
[ARTHUR presses button]
ARTHUR: Oh!
FORD: What happened?
ARTHUR: A sign lit up saying “please do not press this button again.”

‘The Hitch-Hiker’s Guide to the Galaxy’
by Douglas Adam

Leonard Weinstein
March 28, 2016 5:47 am

I retract the plagiarizer statement. I looked at the list of references, and the author has credited previous work.

Steve Taylor
March 28, 2016 5:59 am

Dr. Robert Forward used laser propulsion in his sci-fi novel series “Rocheworld”, the details are well worked out in there- including how to stop.

March 28, 2016 6:34 am

Tantalizing. But does anyone have a sense of how space particles might affect absorptivity? It seems that thermal issues could be significant if sail absorptivity can’t be kept exceptionally low.
Note also the “stability and shaping” issue raised on page 22.

Gary Pearse
Reply to  Joe Born
March 28, 2016 10:03 am

Or how space particles might effect the wafer-sized ship?

March 28, 2016 6:50 am

It seems a difficult task. If the laser drives are satellite mounted in earth orbit, then an equal and opposite beam will be required to maintain the satellite’s orbit. Multiple gigawatt beams increase risks to us earthings.
The wafer scale devices 2g or less, complete with nuclear power source, appear to have the greatest chance of ‘getting somewhere interesting’, but how can we get comms from such far distances, in such a small envelope, with so little power?
I suppose it can be said that if we aim in the right direction then the device must have reached the target and to doubt the achievement it is just being ‘negative’ – a bit like dismissing some of the outlandish climate stories!

March 28, 2016 6:56 am

Well, I read the pdf. BS-phd is my opinion of the piece. An armchair speculation for a sci-fi piece that has never really examined the technology that this is based on. I would suggest a real understanding of Laser energy dispersal would be the end of this speculation…pg

Reply to  p.g.sharrow
March 28, 2016 7:19 am

Could you elaborate?
I’m quite receptive to the idea that the concept has rubber-meets-the-road problems, but it didn’t appear that the author was relying on the probe’s subtending any individual the laser’s beam waist; he seemed to be relying only on the lasers’ phase relationships’ approximating those of a lens, and he then employed the diffraction limit to determine how well the radiation would be concentrated.
Could you further explain how that is inconsistent with “Laser energy dispersal.”

Michael J. Dunn
Reply to  Joe Born
March 28, 2016 1:05 pm

The math is arcane and I don’t have it readily to hand, but it turns out that a laser beam can project a “waist” only out to a certain distance (near field), after which it grows in accordance with the inverse-square law (far field). Moreover, diffraction allows some of the radiation to spread farther out in rings.
I haven’t read the proposal (seen too many of its like already), but I surmise that they haven’t really taken account of the physical limitations on laser beam propagation. It’s a common failing of such schemes.

Reply to  Joe Born
March 28, 2016 2:43 pm

Michael J. Dunn:
You’re correct that the waist length is limited and reduces with waist area. But the point I was making is that the author did not seem to be relying on the waist’s extending out to the probe; he proposed instead to use a phased array: an array of lasers focuses on the probe, producing the effect of a large lens.

Reply to  Joe Born
March 29, 2016 5:01 am

Oops! I misspoke. Beam-waist length increases with waist area, of course. I had said it decreases.

Michael J. Dunn
Reply to  Joe Born
March 29, 2016 1:34 pm

For Joe at 28 Mar, 2:43 PM–
A phased array of lasers is yet another pipe dream. Huge problems associated with that, specifically having to do with phase control. Which involves the laser wavelength stability. Which is limited by the variation induced by the fact that the photons originate from inherently transient sources (truly continuous-wave sources will have near-zero variation in wavelength).
In any case, it hardly matters. The distance at which a “waist” can be projected is not by any means interstellar, so long as you are using array apertures that are not larger than a planet. Figure it out. The equation for the distance to the beam waist is zmax = pi * w^2 / 2 lambda, where w is the beam radius at the waist and lambda is the beam wavelength. The beam radius at the waist is 70.7% of the radius of the source aperture.

March 28, 2016 6:57 am

You mean to say there are conceptual ways to fire thousands of probes to nearby stars and all over our own solar system, collecting much needed data advancing astronomy, science and engineering and even supplying planetary missions, and these concepts never get funding or off the ground? ya don’t say!!
It could be an exciting time for astronomy and science, how many much needed well paid jobs would be created having a developing space industry based around working concepts like this one?
But for the foreseeable future the fact is, we are stuck with political scientific hacks screwing around with data, boring the life out of ‘man made global warming sceptics’ across the planet for no other reason than to financially burden the less well off with heavily inflated energy bills, lowering industrial production and throwing away jobs all in the name of the latest political fad…
I really don’t want to be on this planet when I think about it, can I be put on one of these laser accelerators? lol

Asmilwho
March 28, 2016 7:29 am

Well if this ever happens I hope they do a good job with their security & comms software.
Otherwise we might find the bad guys hack into it and start vapourising people they dont like

TA
March 28, 2016 7:38 am

This sounds like a good way to explore our solar system relatively quickly, once it got up and running. We could put a probe around every significant body in the solar system, in our lifetimes. I like the thought of that. It’s the kind of thing where you can start out small and build from there. I would put money into it if it were up to me, whether it came out of the climate change budget or not.

Reply to  TA
March 28, 2016 5:44 pm

It sounds amazing doesn’t it? It’s just more fluff…

John miller
March 28, 2016 7:50 am

Where is Bob Newhart when you need him?

March 28, 2016 8:15 am

I can’t believe the naysayers on this thread—and on a science blog, no less! I skimmed the paper, and noted that the author carefully discussed many of the potential problems with the concept mentioned here, e.g. how to brake (no solution), how to communicate data from the distant star (some possiblities), how to minimize the danger from interstellar ‘dust’ (some ideas), etc. Yes, it is not a new idea, but the point that the technology—phased lasers, miniaturization, etc.—is now within our grasp is new, and welcome.
When I was a kid, lying on the summer grass gazing up at the stars (which one could see in suburban Montgomery County, Maryland much better than today), I assumed that by the turn of the century we would be on our way to Alpha Centauri. But here we are still, stuck in low-Earth orbit, and fretting about going back to the Moon, and to Mars. Frankly, I am getting impatient, so let’s get on with it. And as for you “Man was never meant to fly” Luddites, back in your caves!
/Mr Lynn

Reply to  L. E. Joiner
March 28, 2016 8:33 am

Writes L. E. Joiner:

I can’t believe the naysayers on this thread—and on a science blog, no less!

You don’t get it yet? It’s because this is “a science blog” (no less) that those who write, read, and comment here have great scientific literacy and familiarity with the federal bureaucracy’s politicized approach to scientific investigation and technological development.
Knowing what we know – in many of our individual cases on the basis of direct experience with “government science” in the various tax-funded federal agencies – how the hell else d’you expect us to regard what is either being proposed as Yet Another Boondoggle or is almost inevitably going to come into being as Y.A.B. by the career mediocrities of Obozo’s Islamic World Outreach Department?

Reply to  Tucci78
March 28, 2016 11:12 am

Yes, “government science” is to be regarded with a jaundiced eye, but you paint with too broad a brush. NASA has done some wonderful things, especially in the realm of astronomical and interplanetary research with telescopes, probes, rovers, and other space vehicles. I see this line of inquiry as an extension of that realm.
/Mr Lynn

Reply to  L. E. Joiner
March 28, 2016 2:29 pm

Protests L. E. Joiner:

Yes, “government science” is to be regarded with a jaundiced eye, but you paint with too broad a brush. NASA has done some wonderful things, especially in the realm of astronomical and interplanetary research with telescopes, probes, rovers, and other space vehicles. I see this line of inquiry as an extension of that realm.

Even granting these “wonderful things” accomplished under NASA’s aegis, what you subjectively perceive as benefits accruing by way of spending power and other resources put into play “in the realm of astronomical and interplanetary research” by this agency over the decades, you must come to grips with the iron law of bureaucracy, which Dr. Jerry Pournelle put pretty pithily many years ago:

In any bureaucratic organization there will be two kinds of people: those who work to further the actual goals of the organization, and those who work for the organization itself. Examples in education would be teachers who work and sacrifice to teach children, vs. union representative who work to protect any teacher including the most incompetent. The Iron Law states that in all cases, the second type of person will always gain control of the organization, and will always write the rules under which the organization functions.

Were that not enough, being the creature of the federal executive branch, NASA is wholly the tool of whatever creature currently flatulates into the big comfy chair behind the Resolute desk, and have we not yet ample appreciation of how the current occupant thereof has proven that any such imposition of malicious political priorities upon the sciences will invariably make of this and other agencies of the executive nothing more or less than engines of usurpation, duplicity, graft and corruption?

Reply to  Tucci78
March 28, 2016 4:53 pm

Re Tucci78 March 28, 2016 at 2:29 pm:
I would welcome a regimen that would enable us to undertake expensive interplanetary science (and any other kind) with no risk of bureaucratic ossification and with complete independence from political tentacles, but must confess that it is hard to see how to achieve this utopian system.
More broadly, the Founders really did not envision a fourth branch of government, an entrenched bureaucracy that essentially operates as a law unto itself. Conceivably a Convention of States (as Mark Levin has proposed) could rein it in with Amendments, requiring ‘sunsetting’ and new enabling legislation, but how that might affect quasi-autonomous agencies like NASA remains to be seen. Arguably the Federal government ought not to be involved in scientific research (or space exploration) at all, but it will be as long as we need a national defense, willy-nilly.
/Mr Lynn

Reply to  L. E. Joiner
March 29, 2016 2:21 am

L. E. Joiner writes:

I would welcome a regimen that would enable us to undertake expensive interplanetary science (and any other kind) with no risk of bureaucratic ossification and with complete independence from political tentacles, but must confess that it is hard to see how to achieve this utopian system.
More broadly, the Founders really did not envision a fourth branch of government, an entrenched bureaucracy that essentially operates as a law unto itself. Conceivably a Convention of States (as Mark Levin has proposed) could rein it in with Amendments, requiring ‘sunsetting’ and new enabling legislation, but how that might affect quasi-autonomous agencies like NASA remains to be seen. Arguably the Federal government ought not to be involved in scientific research (or space exploration) at all, but it will be as long as we need a national defense, willy-nilly.

During the conflicts of the 20th Century, militarized technology came to widespread consideration as conferring perhaps the critical “edge” in strategic, operational, and tactical planning and execution. World War II has been spoken of as “the war of the boffins, and with good reason. Scientific advances manifest as functional “milspec” engineering made the difference between defeat (or disaster) and success (to one degree or another) time after time.
As World War II segued without effective interruption into the perpetual state of Cold War between the First World and the Second (i.e., the Soviet Empire and the other authoritarian Communist powers), the boffins were perceived – correctly – as military assets, with the West having the advantage in both economic power to “push” endeavors in STEM and in the commercialization of technologies “spun off” from military research & development. The glory days of NASA were an unintended (but politically very welcome) consequence of the extension and intensification of the “Boffins’ War.”
To the extent that “pure science” endeavors as well as scientific investigation manifestly applicable in the development of technology continue to prove vital to government’s only legitimate purpose – as the agency to which the citizenry delegate their unalienable individual human right to exert deadly force in retaliation against violent aggression (the “breaking things & killing people” function of the police power in civil society) – agencies such as NASA have defensible reason to exist.
But only to the extent that NASA operations result in “force multiplier” functions accruing to U.S. military capabilities. If there’s justification for “blue-sky” pure astrophysical research, it’s better that the work be funded by other means than tax revenues, and removed utterly from the purview of GS-whatever sphincters controlled by graft-sucking jacks-in-office and other enemies of our republic, emphasis on our “good Muslim schoolboy” Indonesian-in-Chief.

Bureaucracy destroys initiative. There is little that bureaucrats hate more than innovation, especially innovation that produces better results than the old routines. Improvements always make those at the top of the heap look inept.

— Frank Herbert (1984)

Reply to  Tucci78
March 28, 2016 5:54 pm

You’re so full of shit.

Reply to  Sparks
March 29, 2016 1:34 am

Writes Sparks (I’m paraphrasing):

[I just invited the banhammer.]

Let’s see what happens as this post undergoes moderation.
[Well, it went to moderation. And? .mod]

Reply to  Tucci78
March 29, 2016 7:14 am

Writes Tucci78 March 29, 2016 at 2:21 am:

. . .To the extent that “pure science” endeavors as well as scientific investigation manifestly applicable in the development of technology continue to prove vital to government’s only legitimate purpose – as the agency to which the citizenry delegate their unalienable individual human right to exert deadly force in retaliation against violent aggression (the “breaking things & killing people” function of the police power in civil society) – agencies such as NASA have defensible reason to exist.
But only to the extent that NASA operations result in “force multiplier” functions accruing to U.S. military capabilities. If there’s justification for “blue-sky” pure astrophysical research, it’s better that the work be funded by other means than tax revenues, and removed utterly from the purview of GS-whatever sphincters controlled by graft-sucking jacks-in-office and other enemies of our republic, emphasis on our “good Muslim schoolboy” Indonesian-in-Chief.

I don’t disagree. But it would be a stretch to find the funds for expensive space probes like Pluto-faring New Horizons ($700m) in the Defense Department budget, and it is hard to know where else they might come from—private Silicon Valley foundations? A Kickstarter campaign? I’d rather my tax dollars went to space exploration than most of the other frivolities never authorized by the Constitution.
Then, ‘pure’ academic science in general has become so firmly wedded to the teat of government (taxpayers’) grants that weaning would be traumatic. A biologist I know reacted in horror: “Who else would pay for research?” But it can be argued that a lot of the ‘research’ has little point other than the generation of resumé fodder and employment for post-docs who can’t find teaching jobs. Might be interesting to shut down the NSA and the NIH and see what happens. But this is a large topic for another day.
/Mr Lynn

Reply to  L. E. Joiner
March 29, 2016 1:11 pm

L. E. Joiner observes that

…it would be a stretch to find the funds for expensive space probes like Pluto-faring New Horizons ($700m) in the Defense Department budget, and it is hard to know where else they might come from—private Silicon Valley foundations? A Kickstarter campaign? I’d rather my tax dollars went to space exploration than most of the other frivolities never authorized by the Constitution.
Then, ‘pure’ academic science in general has become so firmly wedded to the teat of government (taxpayers’) grants that weaning would be traumatic. A biologist I know reacted in horror: “Who else would pay for research?” But it can be argued that a lot of the ‘research’ has little point other than the generation of resumé fodder and employment for post-docs who can’t find teaching jobs. Might be interesting to shut down the NSA and the NIH and see what happens. But this is a large topic for another day.

It would be a “stretch” because projects like the New Horizons probe are of no arguable military utility, which means that they don’t accrue to the “breaking things & killing people” function which is (as I and Thomas Paine have both observed) the only reason why we (the private citizenry) don’t simply kill the governmentally inclined out of hand as a public health measure.
To the extent that government is allowed to exist, the “goons with guns” role is the institution’s only real justification. Goshwowboyohboy “big science” – except as it facilitate better thing-breaking and people-killing in defense of the Constitution against all enemies foreign and domestic – ain’t something that we should ever entrust to the governing class and their myrmidons.
Simply because “that’s the way it’s been” since the Good War is no friggin’ reason whatsoever to continue throwing pelf and manpower down a succession of ratholes defined by professional grifters, grafters, thieves, power-trippers, sociopaths, psychopaths, and vacuities with Civil Service ratings.
The fact that “big science” researchers (like your biologist buddy) have become utterly dependent upon stolen money (and what the hell else is taxation but theft?) to pursue their investigations ought to clue you and everybody else reading here in on the fact that the perverse incentives imposed by the politicians’ command and control are no more healthy for the sciences than is trailer-cooked methamphetamine for the average high school student.
((Okay, enough with the Ritalin jokes already….))

Reply to  Tucci78
March 29, 2016 7:18 am

Any reason why my thoroughly innocuous comments are going to moderation? Aside from inspiring one ‘Sparks’ to vulgarity, I mean?

Reply to  L. E. Joiner
March 29, 2016 12:10 pm

Asks L. E. Joiner:

Any reason why my thoroughly innocuous comments are going to moderation? Aside from inspiring one ‘Sparks’ to vulgarity, I mean?

Durned if I know. I’ve been on “permanent double-secret probation” for more than a year myself.
I suspect it’s for the crime of eloquence.

Reply to  L. E. Joiner
March 28, 2016 9:03 am

I just don’t understand this attitude. If all you are looking for is a relativistic projectile then this technology is perhaps onto something and may be possible to develop. If you want a probe which can be inserted into orbit then until you have a braking solution – or at least a ghost of a practical idea – it’s as much use as an ashtray on a motorcycle. It’s no good dreaming of our sci-fi fueled youths and boldly exclaiming that if people hadn’t tried stuff in the past we wouldn’t have got anywhere. People guessed that man might fly because all manner of other creatures were doing exactly that. Research doesn’t start with ‘well I’d like to have some currently impossible thing and I have no idea how that currently impossible thing might be achieved but I’m damn well going to sit here researching away until I do – so there!’ What you need is some sort of idea to start with. If everyone sat around bashing their skulls against problems with no glimmer of a solution or even in which direction to look for that glimmer on the principle that with sufficient effort they would get there sooner or later we really would never have got anywhere.

Michael J. Dunn
Reply to  cephus0
March 28, 2016 1:18 pm

Old story. I did a mission analysis (in the 1980s) of an interstellar mission and arrived at the conclusion that the mission duration should take no more than 50 years, in order to be sustainable from a funding and project management standpoint. Skipping a lot of math, this resulted in the derivation of a requirement for a propulsion system that could produce about 1 million seconds of specific impulse. It turns out that such technology exists (look up Birkeland rays), The problem, always the case with high-specific-impulse reaction drives, is that a high kW/kg power supply is needed.
Another approach is direct application of continuous nuclear fission reactions…much more to my taste!
I’m surprised that no one, to this point, has mentioned the Orion nuclear explosion drive system. Dramatic and controversial, but not controversial as to its efficacy. It would work. If we are serious about actually GETTING THINGS ACCOMPLISHED, we will throw over our taboos and prejudices and get on with the show.

Reply to  cephus0
March 28, 2016 6:13 pm

Michael J. Dunn
There’s a job for you, we need a way to send probes across our solar system and to nearby stars. There have been no practicable experiments to date, which is strange.

Reply to  L. E. Joiner
March 28, 2016 8:18 pm

@Sparks March 28, 2016 at 5:54 pm
Thanks for your contribution.

Reply to  L. E. Joiner
March 29, 2016 7:10 am

😉

Reply to  L. E. Joiner
March 29, 2016 8:49 am

L. E. Joiner Says:
“…Aside from inspiring one ‘Sparks’ to vulgarity, I mean?”
You’re just so inspirational, next time wear your big boy pants, lol no offence intended toward you though honestly…

Cornelius
March 28, 2016 8:31 am

Nitpick, but should use lower-case c for the speed of light. When I read .25C it looks like a temperature.

Reply to  Cornelius
March 28, 2016 6:15 pm

Shut up lol

Cornelius
Reply to  Sparks
March 28, 2016 10:53 pm

Ugly to a physicist’s eyes. Irrelevant to probably anyone else.

March 28, 2016 8:36 am

From the article: “Braking to Enter Orbit on Arrival – A very difficult challenge is to slow the spacecraft to typical planetary orbital speeds to enable orbital capture once arriving. This task is extremely difficult as the
initial entry speeds are so high (~ c) and the orbital speeds are so low (~ 10-4 c). Dissipating this much
energy is challenging. We have considered using the stars photon pressure, the stellar wind (assuming it
is like our own solar system), using the magnetic coupling to the exo solar system plasma. None of these
techniques appears to be obviously able to accomplish this task and much more work and simulation is
needed. A simple fly-by mission is clearly the first type of mission to explore in any case to assess the
environment in a given system to design (if possible) an optimized braking strategy.”
Basically they have no idea how you might even in principle go about braking the thing so until they figure that out they have at an outside best imagined a very high velocity interplanetary/interstellar bullet. Experience with climate pseudoscience has naturally enough made me a little gun-shy of statements like “much more work and simulation is needed”. I could of course say the same of FTL space travel and sit around for decades making computer sims on huge fat grant awards. Speaking of which I believe NASA has mercifully at least defunded research into Alcubierre FTL warp drives owing to the current unavailability of the required negative energy density exotic matter. Can’t even bear to look if they’re still funding space elevator research.

Reply to  cephus0
March 28, 2016 8:42 am

Sorry about the carriage returns – hadn’t realised.

Unmentionable
Reply to  cephus0
March 29, 2016 4:51 am

As long as the teleport budget is still good.

Frank Knarf
March 28, 2016 8:42 am

Beware of Motis.

BFL
March 28, 2016 9:01 am

But, but, but, the Saucers have already solved this problem (and beyond), the government just needs to release the secret propulsion systems for commercial use.

March 28, 2016 9:25 am

cephus0 March 28, 2016 at 8:36 am
Basically they have no idea how you might even in principle go about braking the thing so until they figure that out they have at an outside best imagined a very high velocity interplanetary/interstellar bullet. . .

No idea yet. So they should just scrap the concept? Whatever happened to “While the difficult takes time, the impossible just takes a little longer.”
/Mr Lynn

Reply to  L. E. Joiner
March 28, 2016 9:37 am

Trouble is that’s precisely the problem right there. It isn’t even a concept to scrap. There is no concept of how they might brake the thing. When someone comes up with a workable concept then it’s game on again. Meanwhile I appreciate the sentiment but “While the difficult takes time, the impossible just takes a little longer.” is a lovely glib phrase but best applied to poytailed and horn-rimmed advertising executives tackling particularly thorny Venn diagrams. I’m afraid in engineering the impossible usually just takes a little infinity.

A C Osborn
Reply to  cephus0
March 28, 2016 10:18 am

That would depend on the “device” that was sent, small has be recon only, but large means Atomic power. mass and maneuverability, so depending on the Solar System you could use all of those that have been mentioned, not just one of them, plus Solar and Planetary braking. I am not sure how many passes would be required to bring down the speed.
But the first item would be a very large nanotec Solar Wind sail and I mean huge, maybe 100Km across. It is what the Atomic power and mass would be used for the whole time they were going there.
All we get from modern science is doom, gloom, everything is against us and how we CAN’T do things rather than how we COULD do things, this paper makes refreshing change even if it is only half a concept.
I know one thing with your attitude Atomic Energy would never have been invented, after all how could anyone conceive of “Splitting an Atom” and releasing it’s energy.

Reply to  cephus0
March 28, 2016 11:47 am

Well as to your first paragraph I think perhaps the team would have mentioned it if they had a practical braking solution in mind. Second thing is I’m not sure you’re quite getting to grips with these relativistic velocities. For the smallest craft they’re looking at around 270 million km/hour and for the largest craft about 4 million km/hour and I don’t think second passes through the system are any kind of reality unless you can come up with a scheme for the required enormous braking. If you can then the people in the OP article would very much like to speak with you I feel confident in asserting.
I know, I really p1ss people off with the old doom and gloom! Thing is though that is how I think science should be done. If someone, or even I, come up with a novel concept then it is everyone’s including the proposer’s, duty to do their utmost nest to knock it down. Only when no one can does it begin to look exciting. False confidence in an effort to look enthusiastic is what makes me gloomy because then everything gets reduced to children playing in a sand pit. Being critical is not the same as being negative. I too find it interesting that they perhaps now have the laser tech down to a state where they can propose this but that doesn’t mean I’m going to go all doe-eyed and conveniently forget about the problems at the other end.
As to your final paragraph – I couldn’t agree less. Atom smashing became a reality because of the slow build up of experimentally supported physical theory until the point at which it was realised that to do such a thing was within the scope of the science and technology of the day. Had Democritus of Abdera proposed splitting his newly proposed atoms he would rightly have been laughed out of the academy because there was no theoretical or physical framework for attempting any such thing. Things only happen in science when their time has come and all the parts are in place to make them a reality. Maybe one day this interstellar proposal will have it’s day but by the looks of things that isn’t this day.
We used to submit projects for funding and they were judged on their likelihood of success because we have finite resources for these things. We also do blue-sky theoretical research for the sake of knowledge and – after all – who knows what may come out of it. What we don’t do – or rather didn’t used to – was run around like farmyard chickens, hemorrhaging tax payers cash on all manner of highly likely blind alleys. It’s a major component of why science is going horribly wrong and the tree is in dire need of a good shake.

Michael J. Dunn
Reply to  cephus0
March 28, 2016 1:11 pm

(Spoiler Alert) This has been presented in the professional literature: jettison the outer portion of the laser sail and use it as a reflector to shine the laser light back onto the remaining sail on the spacecraft, thus applying a braking thrust. The sail outer portion gets accelerated farther along, but it serves the purpose of slowing down the spacecraft.

Reply to  cephus0
March 29, 2016 4:53 am

Oh lordy if only those guys had known about that suggestion! Email them quick and you’ll be project director before you can say “I haven’t thought this through yet”. But seriously, if you read the article they are talking about acceleration phases lasting minutes after which it’s a free coast to destination. You aren’t suggesting they can target a 1 m sail with a laser from parsec distances – are you? I know that’s how the Moties did it in The Mote in God’s Eye but that was sc-fi for entertainment purposes.

tommoriarty
March 28, 2016 9:48 am

In “Encounter with Tiber,” a SF book by Buzz Aldrin (1996), the Tiberian ship used lasers pointed at its solar sail for propulsion. This was considered “hard” SF. I give it extra credence when Buzz’s name is attached to it.

Reply to  tommoriarty
March 28, 2016 10:45 am

A friend (to whom I sent the link to the paper) reminds me that the late Gerard K. O’Neill (The High Frontier: Human Colonies in Space [1976], founder of the Space Studies Institute at Princeton) proposed using solar satellites to power light energy to a ship with a sail.
/Mr Lynn

gnomish
March 28, 2016 10:05 am

The idea of interplanetary travel by light was mentioned by Jules Verne in From the Earth to the Moon.
Solar radiation pressure on earth, 1361 W/m2 at 1 AU, is 9.08 µN/m2 or 0.0013 oz.in.
There is no ‘mars in 30 minutes’ from radiation pressure.
The pressure is infinitesimal and requires lots of time to achieve any acceleration that can be measured.
Colossal lasers that could produce any pressure you could feel are unavailable to the mortal man.
The idea of a solar sail is one thing- the sun is already there and radiates in all directions so it’s stationary.
Laser powered light surfing is not remotely plausible to me.

LdB
March 28, 2016 10:06 am

Not sure what this all has to do with climate science except some very loose argument about better use of the money which Eric does in one small sentence. I am not sure people would however accept having a raft of tax and legal frameworks is necessary for what is essentially a science funding problem. I have a racehorse system that I am sure would benefit from more funding as well if we are going down this argument.
Now had Eric gone the path that would could fire all the politicians and climate scientists into space, I might have seen a more direct link but probably not a newsworthy article.

A C Osborn
Reply to  LdB
March 28, 2016 10:21 am

It does not need to have anything to do with Climate at all because AW used to have a different heading to this web site. Basically anything to do with Science.

Reply to  A C Osborn
March 28, 2016 10:49 am

The heading used to be, “Commentary on puzzling things in life, nature, science, weather, climate change, technology, and recent news by Anthony Watts.”
Maybe when the Climate Wars have been won (by the good guys, of course), AW will go back to that broad charter.
/Mr Lynn

co2islife
March 28, 2016 10:59 am

NASA Relativistic Interstellar Laser Launcher: We could do it NOW, for the cost of the NASA Climate Budget

IMHO this is one of the best ways to address Climate Change…its Opportunity Cost. We are wasting tremendous resources on nonsense, while more important research goes unfunded. NASA doesn’t even have a replacement system for the Shuttle, and they are wasting their money on climate research.

Earl Smith
March 28, 2016 5:09 pm

In addition to the SF novel “Roche world”, Robert Forward prepared a government study for the USAF about 30 years ago (which I had a copy) detailing how we could build a micro wave powered probe that could do the .25c flyby. ( Starwisp ). Because the sail is an array of wires (prepared by printing the wired array on plastic and then letting the plastic evaporate in space), you also have the power from a rectenna for the flyby.
For larger payloads there is the possibility of using the same microwave that launched the bird to do the deceleration by physically altering the sail with an annulus that receives the beam and then reflects it off the inner sail to stop at the destination.
We now have studies showing that we can use microwaves to accelerate a space craft that is deployed at 30,000 feet to orbital velocity while the craft is within the beam (roughly 150 degree arc) . The economics are favourable at roughly our current launch rates. Something that the laser concepts do not achieve. (with a massive computer crash I lost the citation – but it a brief mention within the last couple months on Jerry Pournelle’s site)

Michael J. Dunn
Reply to  Earl Smith
March 29, 2016 1:45 pm

There is an outfit called “Escape Dynamics” (look it up) who purport to be able to do this. I wouldn’t hold my breath. These are weapon-class radiation beams and I wouldn’t want to be at the catcher’s mitt.
What are the safety levels of serious power transmission, say a thousand horsepower (~1 MW)? Safest is by rotating shaft (think ocean liner propeller). Next safest is by electrical cable–but don’t touch! After that, if we use photons, we have the very definition of a beam weapon. Not safe at all. It can cut through metal like a blowtorch through cheese.

March 28, 2016 6:31 pm

Let’s just work out how and find a way to send probes to other planets fast. if it is possible it can be done. how is all that troublesome CO2 doing these days? if they can adjust polar ice data and temperature data, maybe they can adjust the CO2 data.

Jon in TX
March 28, 2016 7:26 pm

What good would it do to send one. Unless it’s coming back, there’s no way to retrieve any information from the destination.

Reply to  Jon in TX
March 29, 2016 9:06 am

Obviously you could send another laser accelerator to the destination and have a two way transport system.

gallopingcamel
March 28, 2016 9:35 pm

Real space travel requires nuclear rockets with at least 3,000,000 times more energy per kg of fuel than chemical reactions can supply. Even with nuclear rockets it will be necessary to collect fuel in transit as proposed by another NASA scientist long ago:
https://diggingintheclay.wordpress.com/2013/06/17/bussard-revisited/

Reply to  gallopingcamel
March 29, 2016 10:55 am

Real space travel requires energy, explosion drives are not an advantage…

Michael J. Dunn
Reply to  Sparks
March 29, 2016 1:52 pm

I beg your pardon? You are perhaps under the misapprehension that nuclear devices are deficient at producing energy? You haven’t read about the Orion system concept? Check out “Project Daedalus.”