Looking at the future of Low Earth Orbit

One hundred kilometers above the Earth's surface space is starting to fill up with debris, with hundreds of now defunct satellites and tens of thousands of smaller bits of waste.  As the cost for launching into space continues to go down the volume of satellites will continue to rise.  While we are unlikely to see a dramatic loss of orbiting equipment as portrayed in the movie Gravity, there is a risk that the volume of debris could reduce the overall life expectancy of spacecraft in more crowded orbits.  Researchers from around the world have suggested various ways to clear orbits, ranging from designing satellites that will intentionally fall back to Earth at the end of their useful life, to using high tech harpoons, and using lasers to slow down materials sufficiently for them to burn up in the atmosphere.

As of May 2019, there have only been handful of small-scale experiments intended to test some of the proposed methods of eliminating space debris.  While the results for these removal methodologies appear to show positive results, humans have yet to establish a standard for cleaning our space-based messes.  While all reasonable solutions to space debris should be given consideration, this article will make an argument for the use of satellite-based laser platforms as a way to control space debris.

Lasers can be used in two primary ways to eliminate space debris ablation and vaporization.  For most readers when they think of using a laser to clear space debris, they are likely thinking about vaporization.  Vaporization is achieved by aiming a strong laser at a piece of material as long as it takes to heat the material enough for it to be broken down into microscopic components.  This requires a very strong laser, several megawatts, and as a result a large amount of power.  The approach preferred by researchers at NASA deals with ablation.  Laser ablation happens when a strong laser is focused on a target for several hundred nano-seconds, this very short pulse is sufficient to cause microscopic pieces of material to be ejected from the target material, while leaving the remainder of the target seemingly unscathed.  As microscopic pieces are ejected from the target material, they create a small amount of thrust that causes the space junk's orbit to change.  Eventually the changes in orbit caused by the ablation of the space debris are sufficient to send the material back into the Earth's atmosphere, where the remainder of the debris will burn up.  Because ablation is only burning enough material to change the orbit of the debris, the overall energy requirements are drastically lower than vaporization, the tradeoff that it will take more time to clear out materials.

Currently there are proposals for both ground and space based laser platforms that could be used for clearing orbit.  According to this NASA paper, a single space based laser would be massive, where the solar panels alone would need to be over 500 meters in diameter to supply the roughly 108 Megawatts of power the laser would require.  At first glance a massive solar array in orbit would seem prohibitively expensive, such a massive undertaking needs a longer-term perspective.  Early in the life of the Anti-Debris Laser System (ADLS), almost all power generated by the solar arrays would be used to clear debris and maintain orbit.  Over the years the volume of debris would begin to drop off and soon our ADLS would have a power surplus and the ability to transmit that energy over a long distance.  The primary debris clearing laser could be augmented by a collection of smaller energy transmitters.  Much as the International Space Station now serves as energy source and orbital platform for a range of experiments, the ADLS could serve both as platform and power source for countless future scientific projects.

One extreme example of the ADLS being used as a remote power source would be for low Earth orbit satellites proposed by the European Space Agency.  These air breathing ion engines are intended to capture the rarified gases that orbit the Earth and use these materials to supply fuel for their ion engines.  A challenge facing current design proposals is the added drag that their solar panels would supply.  If the satellites were designed with the ability to receive additional energy from a directed energy source they would be able to get by with fewer solar panels, which would both reduce the weight of the space craft and reduce drag, a nice little win win.

Future Scenario

April 12th 2051

A new satellite communications start-up has submitted a power purchasing agreement from the United Nations Space Agency's ADLS division.  According to their filing, they are looking to buy sufficient power to supply a constellation of at least 2500 Ultra Low Orbit communication satellites.  These satellites will have some of the lowest orbits ever authorized to a non-governmental body.  In a press release yesterday their spokesbot said "Fastest Trade is looking forward to working with the United Nations Space Agency to help provide 7G Micro Latency communications to the global market of ideas.  Our technology will allow consumers around the world to shave critical nano-seconds off of their communications."  The press release was positively received by several High Frequency firms.  A researcher from the European Space Agency noted that without the external power provided by the ADLS, the orbits of the Fastest Trade satellites would need to be several kilometers* higher than what they have filed for.**

(Scenario 2)

12 hours ago disaster struck Bigelow Research Station El Dorado, due to a series of software errors the station's on board solar panels stopped orienting towards the Sun.  Seven minutes after the error was confirmed support teams from available ADLS platforms were able to add the El Dorado to the orbital power grid user base.  While investigators try to determine how and why the solar panels ceased to function, researchers were able to continue their various projects.  Currently the software team is pointing fingers at an unauthorized 3rd party addition to the solar control platform.

* yeah the scenario is fictional, but I do want to say its on the hard science side of things and the several kilometers value is basically random.  That being said lower drag with a better engine should mean a lower orbit I just don't know by how much.

** honestly high frequency trading is the only reason I can think of  as a long term use for satellites at a really low orbit, that being said I hope there are more generally beneficial uses of this concept.

I hope this idea was interesting, it was inspired by a friend asking me about the potential for using existing satellites and space debris as a source material for future missions.  If you are interested in ideas around re-using old satellites, feel free to check out this post I did a few years ago

Questions and comments are welcome

black body cooling on venus

a personal question, considering the incredible heat you find on venus, could a narrow band black body thermal radiator similar to that being developed at Stanford (other people are probably doing the research but, this is the team I am both aware of and find when I do a quick search), be developed for the atmosphere of venus.  On a planet with an incredibly thick atmosphere that holds onto heat harder than an action star hanging off of a helicopter in a movie, are there parts of the electro-magentic spectrum, that one could successfully dump heat into the void of space.

Making Gravity In Science Fiction

This blog has highlighted on several occasions that I am a massive sci-fi nerd (if this is news to you, this is probably your first time reading here).  When science fiction writers or TV producers have a space ship generate (or simulate) gravity they achieve it in three major ways.  Spin the ship, in movies like Interstellar or 2001 a Space Odessey, the crew is provided with something akin to gravity by spinning part or all of the ship.  This rotation effectively pushes crew members outward and the ground pushing back feels something like gravity.  In the TV show The Expanse (which I highly recommend, the more people who watch it the more likely I'm going to get the 30+ seasons of the show that I desire (and now I jinxed it))(back to the expanse) in the show humans have created advanced engines that are so efficient that ships can be in almost constant acceleration, this means that so long as the ship is under thrust, crews will experience some degree of faux gravity.   Another alternative is the use of "mag boots" specially designed footwear or general attire that has the ability to be attracted to the surface of the ship when crew members need it to be, and when they move their foot up, the magnetic attraction is removed.  This solution is incredibly reasonable, unfortunately, no one seems to have made a show where people in "mag boots" mode actually looks like only their feet want to go down.  (this is not to say doing so is easy, just an observation that it would be cool to see a space battle where mag boots are in use and while a crew member is reloading they just let the empty magazines float there, or less dramatically, while fixing an engine crew members are surrounded by their tools floating nearby.)

The most popular option for ship,s gravitym hand wavium generators.  Hand Wavium Grav generators are popular in , Star Trek, Star Wars, Earth Above and Beyond, Farscape, Stargate...... read all of the shows.  What irks me is that writers generally ignore how weird the behavior of ships gravity is.  (the one exception that does come to mind is the first episode of the TV show Enterprise (the prequal Star Trek show with Scott Baccula), and all they say is that there are weird points in ships where the gravity doesn't quite work.

What would be nice is a middle ground from truly hard science fiction solutions to simulating gravity and just getting rid of the problem with a quick phrase that only power nerds care about.  A "gravity laser" for space craft.  A reasonably advanced civilization might be able to create a narrow beam of gravity that could provide a pulling force on the entire ship.  What is cool about this technology, is if this attractive force is only effective in a single direction you also have a means of reaction-less thrust, helping to minimize how much space the ship "needs" for fuel.  While this approach is still very much fictional, to me it feels a bit more grounded.

I hope you enjoyed the post and if you have any questions, feed back, thoughts, please feel free to comment.  I will try to add a drawing later tonight.

Riding the Centaur (a long term plan for putting research satellites in orbit around Alpha Centauri)

Stopping when you are going really fast is hard, stopping or slowing down while going really fast while flying through the vacuum of space is really hard, slowing down while going really fast in space without using fuel wicked hard to do.

Breakthrough Starshot, the joint initiative between Stephen Hawking and Russian Billionaire Yuri Milner, discussed in the post Additioanl Uses for the Hawking Milner Interstellar Probes (sorry I didn't know the name of the initiative, if I had studied journalism or writing I would feel far more guilty about the mistake), is currently outlined as a fly-by mission, similar to how NASA's New Horizon spacecraft whipped past Pluto.  As stated before, the faster you're going in space the harder it is to slow down.  For an initiative like Breakthrough Starshot slowing down is probably right out off the table for the first generation of probes, the reason is simple, any fuel the probe would carry with it, would make the mission that much more difficult to get to a useful speed, and the amount of fuel you would need to slow down from .2C, well we won't be doing the math today, but it would be a poop ton (possibly quite literally).  

If mission designer's at Breakthrough Starshot can't use fuel how could they slow down their probes enough to achieve orbit?  

Quick answer, using probes to focus the star light of Alpha Centauri (this will not be as easy as it sounds)

The long answer:  The initial generations of Starshot probes will most likely be relatively simple in design, a large surface area solar sail attached to the actual sensor and communication suite, at least at launch, it seems (to this rather uninformed nerd) unlikely the space craft will try to remain attached to the solar sail once outside of the range of the laser propulsion system.  Why would the probe keep carrying something that can increase the likely hood of colliding with a piece of material that could throw everything off course?  As technology gets better it may become possible to create a solar sail material that can be manipulated in ways similar to how blinds can be manipulated to alter how much light can enter your home.  The ability to create a solar sail that can dynamically alter its shape after deployment would open up a world of possibilities, now the probe can protect their sails across the interstellar void, patiently waiting until the probe gets close enough to its target star and start to put on the breaks.  

(note to self add some drawings 6/1/16, dear readers please remind me to make some artwork)

Alas, as noted before, putting on the breaks when you are going at such extreme speeds would be difficult under even the best of circumstances.  In out solar system sunlight doesn't have sufficient density to provide any real pressure much past the orbit of Mars*.  With Mars having an average distance to the sun of about 1.5 AU, for sunlight to reach Earth at 1 AU it takes 8 min 20 seconds, or 12 min 30 seconds for light to reach Mars' orbit, this means if you are going at 20% the speed of light, that means you have just over an hour to use sunlight to slow yourself down, this makes it unlikely that your probe will sufficiently slow down before burning up.  

But we aren't thinking about the individual probes, Starshot probes are like ants in a colony individually cool but not super effective, but when they work together they can achieve wonderful things.  The probes that are able to control their sails will work together.  A simplified mission profile would look something like this.  Wave A is sent out, they are definitely all going to die horribly, when approaching their target stars, they reconfigure their sails to act as Fresnel lenses, focusing starlight towards those who will come behind them this focused light will increase the amount of breaking force supplied to the probes.  The waves will continue, some waves will be launched with lower initial velocities, the slower you are going when you leave the more time you will have to break on the other side, but it also means you are waiting that much longer to get results.  Eventually you will have a steady string of probes focusing the light of a far off star further and further out, providing a breaking zone for larger probes who come down the line.  Many years after the first wave of probes either burn up in the fires of Alpha Centauri or are left to wander the void beyond, a probe massing a whopping 10 grams slows enough to enter orbit.  This probe left Earth going a mere 5% the speed of light, but has now slowed to a much more manageable 22 km/s to begin its orbit around Alpha Centauri A.  

The advantage of this approach is that all of these probes could be made and launched incredibly cheaply, and if an individual probe is lost, no harm no fowl.

The negative, and it is potentially a big one, it will take at least 80 years for the suggested 10 gram probe to get all of the way to its target destination.  If we don't figure out how to make a space ship that can carry enough fuel to park itself in orbit or some truly sci-fi sounding propulsion method no big deal, humans weren't going to really be heading that way in the near term anyway.  On the other hand, if it turns out we can make some kind of FTL drive, or a fusion powered starship, we suddenly have a rather dangerous traffic jam of dangerous bullets on a potentially intercept course with your ships.  Who knows?

Another version of this idea, will be written about later, which will instead be optimized for helping really really big spaceships get into planetary orbit.

Any suggestions, questions, please leave a comment.

*citation will be added, as of June 1 2016 I am going off of recollection of some research I did.

Additional Uses for the Hawking Milner Inter-stellar Probes

In the middle of April Steven Hawking and Yuri Milner announced plans to invest roughly $100 million into researching technologies that would allow incredibly small spacecraft to be accelerated by laser light towards Alpha Centauri, hopefully going fast enough that the probes would reach one of our nearest celestial neighbors in under 20 years from launch day.  Many nerds, myself included, got a tad excited, but there are nay-sayers, as well as those who wonder why we should invest in such projects.  Why should we spend so much energy creating probes that may or may not A) reach their intended foreign star, B) provide data that probably could be gleaned by telescopes based in this star system, and C) produce any tangible benefits to humans here on earth.  In order this article should respond.
A) Will the probe reach the target destination?
Answer:   this is the wrong way to phrase the question, these probes will mass less than the spare change in your pocket (assuming you aren't hoarding coins in your pants).  The rational behind this kind of mission would be similar to that of how ant colonies work, individual ants may not make it back to the colony, or necessarily provide that much information about the world they explore, but thousands of ants cumulatively do achieve great things.  The many hundreds or thousands of probes we send out towards Alpha Centauri will most likely have at a respectable number reach their target trajectory.
B)  Will the data be better than that we can get from space based telescopes that we will deploy in this solar system?
Answer:  Hard to say, the size of the probes will mean the type of data will be different than that collected by radio or optical telescopes.  The kind of data they could collect will be unique, and that should be worth considering.  For example the chemical composition of the heliosphere of Alpha Centauri, nano-scale chemical tests could differentiate what molecules are actually found floating around empty space and other stars.  If the probes have visual sensors they could take snap shots from angles that are simply not possible from another solar system, even low resolution images at a different angle can provide tremendous clarification on what might be found.  Better space buffs will probably have better answers than me.
C)  What are the tangible benefits?
Glad you asked, this is where creativity comes in.  We are talking about infrastructure designed to launch and accelerate relatively large numbers of super tiny probes into space to 0.2C (which is amazingly fast)
Asteroid Deflection.  (hardish)
With the ability to launch these probes, humanity can start being more proactive about how it deflects asteroids.  As soon as we detect potentially threatening asteroid orbits, we can bombard asteroids with micro-impactors, the specific impulse for a given impact will be low, the chance of hitting the asteroid will also be relatively low, shooting at moving targets, from a moving object, is hard to do, but it is easier to change a trajectory years out, as opposed to the Armageddon approach (where we wait until the killer is within the moon's orbit).  (it is unlikely that the probes would be going at 0.2C (even if the platform could get probes going that fast) as there will be less time to accelerate)
Space Exploration Augmenting. (depends on the target, easy to hard)
Depending on how much targeting control the probes have, one use could be uncovering surfaces on asteroids and moons, similar to how NASA intentionally shot the LCROSS at the Moon to look for evidence of water.  This would make future space mining initiatives far more targeted.
Alternate Propulsion for Larger Spacecraft (really hard)
One of the craziest proposed methods for powering large scale spacecraft capable of brining humans along for the ride is Project Orion, a vessel powered by the detonation of successive nuclear bombs.  For those who don't want to follow the link, imagine a space craft in with two primary features, an upper section, filled with crew quarters, supplies, sensors etc... and a lower section comprised of a giant plate, connected to the upper section by massive hydraulic pistons.  While on course towards another body the spaceship would drop a nuclear bomb into position, where the nuke would explode, causing some of the push plates material to evaporate off and provide force.  In the current culture we live in, launching a spacecraft into orbit with hundreds, if not thousands of nuclear bombs is just not feasible.  But the core idea can be reused, instead of having nuclear bombs push against the plate, hundreds of probes hitting a large spacecraft at 0.01 C or above could conceivably achieve the same goal.  A long term space craft could gain velocity from the impact of tens of thousands of accelerated probes.  There are some challenges (understatement of the day for me) with this idea.  The probes would need to hit the ship with incredible accuracy, too much deviation from the optimal impact angle could cause the ship to spin excessively.  The period where the probes could actually be used to augment the acceleration of the ship are also limited.  The efficacy of this means of propulsion would require quite a bit of study.
Counter arguments to this suggestion should also be considered.  As the smaller spacecraft are primarily being powered by Earth based laser energy, why not directly accelerate the larger craft with the lasers.  For short term missions I agree, if you are close enough that the laser can provide sufficient power, for the love of god, use that as an energy source.  This strategy is intended for when the larger spacecraft is beyond the point where the laser light is dense enough to provide useful power.  It is only at that point where it would make sense to use the impactor suggestion.

If you have any questions comments, feedback, please feel free to write something.

The Next Generation of Electric Submarines

(please note this post is a shameless plug piece for my job application at OpenWater Power)
Military submarines are the silent hunters of modern warfare, for nations like the United States, Great Britain, and Russia, these vessels are frequently nuclear powered, allowing for vessels to go years without needing to surface (if the vessels did not have pesky humans requiring fresh food).  Other countries have less sci-fi sounding diesel electric submarines, where the vessels will surface as needed to bring in air to allow the diesel generators to recharge the vessels on board batteries.  Newer vessels are even looking towards hydrogen fuel cells, I would like to suggest an alternative, a vessel that possesses "hot swappable" power packs composed of Aluminum water fuel cells.
Aluminum water fuel cells have an incredible ability to store energy, over 2.00* kWh/liter, all without requiring air to be added to the system for power production.  Navies of the future could design vehicles that exclusively use these swappable fuel cell systems to power the vehicles energy needs.  By eliminating the requirement of a mechanical generator and the associated acoustic dampening vessels could be made smaller, contributing to the difficulty of being detected.  Depending on the design strategy of the organization creating these new fuel cell based submarines, the swappable elements could also include replacement air supplies, food stuffs and other materials for long term operations.

For navies working to extend their reach more covertly the swappable fuel cells could be hidden inside of shipping containers and said containers could "accidentally" be lost at sea for ships to pick up reserve power, the logistics would be complicated but not beyond the abilities of a mid-sized blue water navy.

Ok back to class work, the StartUp Institute is kicking my butt and I need to keep up with the torrent of projects and homework.  I will try to make some sketches during my lunch break, although it wouldn't be that crazy for the swappable fuel cells to go into bays similar to the ICBM launch tubes found on Ohio class submarines.

*A previous version of this post listed the energy density as 200 kWh/liter, not the official 2.00 kWh/liter, I apologize for the confusion, I did not read the specification as closely as I should have.

Depressing Foods of the Future

Articles discussing how species of bacteria have adapted to metabolize varying types of plastic.  One can imagine a sci-fi writer having the most impoverished part of a planets population eating foodstuffs derived from the bacteria that have consumed waste plastic.

*Yeah I know this post was short, I may write a short scene later, but I wanted to get better about posting, sometimes length will take a hit, which may or may not be a bad thing, you decide

Making Faster Than Light Travel Safer (for the people at your destination)

The Alcubierre drive is currently considered one of the most plausible means of an intelligent life form creating a faster than light vessel.  Needless to say, this is awesome.  Unfortunately there are some potential risks that come with violently bending the universal speed limit of light.  In rough terms, the way an Alcubierre drive would work involves warping space time.  By expanding space time behind the space craft, while simultaneously contracting space time in front of the vessel, the ship is able to isolate itself from the universe at large and get from point A to point B really fast.  So while this is really awesome, the contracting of space time at the front of the ship has a strong potential to become a rather dangerous weapon, the contracted space time would pull in dust and gases through out the journey, forming a super dense plasma, when space time returns to normal, all of the energy in that plasma is released, potentially fatally for the planets in the star system the ship was trying to visit.
Generally speaking, explorers aren't trying to kill the star systems they are visiting, to prevent the built up energy from being destructive, there are a few options.  One simply aim the ship so that when you stop, you are unlikely to kill anyone with the blast of energy.  Two limit your travels to relatively short hops, minimizing how much energy is built up.  Three (my idea), create a pocket universe in front of your ship.  A group advanced enough to create a faster than light ship, might also be advanced enough to create artificial pocket universes.  These artificial pocket universes could be generated right in front of the ship, providing a temporary storage volume for untold quantities of energy, ideally, the super hot plasma would be stored in the pocket universe where the energy could be slowly let out.  This torrent of energy could assist in allowing the ship to power up when it moves on to the next star system.

How Powerful are Phineas and Ferb

I watch kids shows, too many, I fully admit it.

On the show Phineas and Ferb, there is an episode, "Escape from Phineas Tower"  (Episode 315a) where the titular characters create a machine that within less than a day is able to enclose the entire galaxy.  This opens up an interesting question, how powerful of a civilization are Phineas and Ferb according to the Kardashev scale?  (I don't know who asks these questions really, but it is a good chance to do some math)  A quick explanation of the Kardashev scale, it serves as a means of scientists to roughly gauge how advanced a civilization is according to how much energy they can manipulate.  The scale is named after a soviet astronomer by the name of Nikolai Kardashev.  According to the current scale there are 3 types, a Type 1 can manipulate the total energy of a planet roughly the size of planet Earth (10^16 to 10^17 watts), a Type 2 civilization the power output of a local star (4*10^26 watts), and finally Type 3 where the civilization can capture the power output of their entire galaxy (4*10^37 watts), basically a boat load of power.

These values get us to a starting point of how to calculate how powerful Phineas and Ferb are, we know how much energy a given civilization type produces, and we know Phineas and Ferb's creation creates a barrier that encompasses the galaxy.  What we don't know exactly how quickly the barrier encompasses the galaxy and how thick the barrier is.  Both of these values are incredibly significant to our calculations, the thicker the more total energy required, the faster the more power production.

For me the first thing I want to calculate is the overall surface area of the barrier, for sake of convenience I am assuming a completely smooth surface and that the barrier is spherical, this makes the calculations a tad easier.  Much like the edge of the atmosphere the edge of our galaxy is not an instant transition from something to nothing, the density of stars tapers off, for convenience I will say this edge is at 50,000 lightyears from the center of the galaxy.

For the kind of math I would like to do, it is necessary to convert from light years to meters.

Using the above calculations we know that 1 ly or light-year is 9.461E+15 meters, or in terms that normal people use, 9.461 trillion kilometers, that's a big value.

Now that we know how many meters are in a single light year, we can multiply by 50,000 to get the number of meters for the radius of the galaxy.



From the above calculations we find our answer spells out to four hundred seventy three quintillion meters (4.73037E+20 m).  Honestly I am having a hard time properly coming up with a reference for how big that number is.

We now know our radius, with that knowledge calculating the surface area of our sphere is a pretty easy equation from high-school geometry, seen below.




The initial estimation will assume that the barrier is a massive sheet of graphene,  The choice of graphene is relatively arbitrary, but has the advantage of being a known material with an estimated surface area for a given mass (specific area), 2630 square meters per gram.  It is a relatively easy process of dividing the area of the sphere by the specific area to get the mass of the barrier.*



After this plug and chug we find that the graphene barrier has a mass of 1.069E+39 grams, to put that in perspective the Earth, has a mass of "only" 5.972E+27 grams.

Great, we know a lot of numbers, but how do we calculate the Kardashev civilization class of Phineas and Ferb.  We use one of the most famous equations in physics e=mc^2, using this equation we can calculate how much energy it would take to create the mass of the barrier**

The final answer is getting tantalizingly close, we now know the energy required to produce the mass of the barrier is 9.61E+55 Joules, a boat load of energy.  All that is left is to estimate the wattage of the system and from there we can guesstimate what Kardeshev civilizaiton class we have going on.  Calculating wattage is generally relatively straightforward, you divide the number of joules by the number of seconds it takes to release that energy.  First I will calculate how long it would take a Type 3 civilization to build this barrier.  This simply requires we divide the energy of the barrier by the power output of a Type 3 civilization
(9.61E+55 J)/(4E+37 W)=2.4E+18 seconds
That is the equivalent of 76 billion years, that means a civilization capable of capturing all of the energy of their galaxy would take over 6 5*** times longer than the universe has been in existence, to create that barrier.
On the show this takes less than a minute, but making life easier, it will be assumed that the barrier was built in 100 seconds.
(9.61E+55 J)/(100 s) =  9.61E+53 Watts  according to the wikipedia entry on the Kardashev scale, the entire visible universe only has around 10^45 Watts of power available, this would lead us to assume that Phineas and Ferb are the avatars of godlike beings whose rule encompasses a range of universes.

*For the general case we would arbitrarily designate a thickness for the barrier and the material the barrier is comprised of.  So long as the assumed thickness of the barrier is less than 500 light years there is no real need to do a complicated volume calculation, as the second radius is less than 1% greater than the original radius.  If you are so inclined to make your calculations overly accurate or make the barrier incredibly thick, calculate the volume of the larger sphere, and subtract the volume of a 50,000 light year sphere.  With the barrier's volume calculated, divide the volume of the barrier by a selected material's density.  Now you can rejoin the math above.
**  I am making the assumption that all of the barriers mass was created through some kind of matter synthesizer, this is because the episode doesn't show the barrier requiring any mass feed-stocks, that and it makes my life easier.  If some one wants to go crazier on details, please feel free.  Also I acknowledge this calculation ignores the chemical energy of the bonds in the graphene, if memory serves that additional potential energy should be negligible to the system's overall value, please correct me if I am wrong.

*** edited 12/14/2015 I forgot that the universe is currently estimated to be 13.82 billion years old, for some reason I was thinking 12 billion years, amateur hour malarkey I know

Making Universal Translators Lazy in Sci-Fi

A common trope in science fiction stories is that most species have some kind of universal translator that removes at least one barrier of communication between species.  Here's my quick question, why have tv producers not embraced characters mouths not syncing up with the audio, considering each party is hearing the audio differently, would it not make sense for their mouths to not move in a predictable fashion, this would make over dubbing so easy, and you could localize the show super duper easy.

This quick rant was inspired by stories of the teleporter in Star Trek The Original Series, which was created as the production company did not have the resources to actually make landing vehicles that would appear on set locations.  While my suggestion would be a cost saving, I really doubt it would inspire any cool creations.

Sci-Fi Spaceship Idea

This has no bearing on reality, and the idea is relatively vague, oh and it is dependent on a really crappy understanding of Schrodinger's Cat.  Sci-Fi writers feel free to use.

The Starship Gumdrop was on the run, speed had kept the crew alive for the last five days.  The Gumdrop had stumbled into an Inguat military convoy.  Reactors had been pushed to the limit and could give no more.  The captain had no choice but to activate the Cat.  No one outside a research lab had ever been able to understand how the hell the Cat did what it did, but it was amazing.  Within seconds the interior of the ship would become completely indeterminate with respect to the outside world.  Every element of the ships interior was both everywhere and somewhere.  Now, when the Inguats finally got within firing distance it would be almost impossible for critical interior systems to be targeted in the first volley.  The Cat was far from perfect, once the interior of the ship had been impacted the defense was gone, the quantum uncertainty found inside the ship would collapse and the crew would be vulnerable again.  Even if it only meant surviving one volley after shield failure, the Cat was better than nothing.



This idea was partially inspired by this Scientific American article involving the impact of gravity on macro-scopic instances of Schrodingers Cat.


A crazier version could involve multiple vessels somehow sharing the same interior at the same time, as the ships are destroyed only the remaining vessels continue to hold the shared mass until only one vessel remains.  This provides the crew safety within a larger swarm.  I hope you guys enjoyed the idea.

Changing the Light on a Thousand Worlds (or something)

This idea has been mocking me for completion, on my desktop, for let's say at least 6 months.

Space Exploration is, hopefully, the destiny of the human race and in some distant future we will try to colonize the wider galaxy.  One of the challenges of colonizing other planets is the available sunlight.  Some of the most common stars in the galaxy are red dwarfs, so if we can figure out how to make life around a red dwarf work, you can make colonization work in a large swath of the universe. The reason red dwarfs are potentially difficult to colonize is the amount of energy they radiate.  Unlike brighter stars, including the Earth's yellow sun, red dwarfs burn slowly, releasing the energy of fusing hydrogen and helium over a span of trillions of years.  This rate of energy output means that planets orbiting a red dwarf will be unlikely to receive enough energy to power the engine of an Earth like ecology. 

One potential solution, a modified Dyson swarm. For the uninitiated a Dyson swarm is a massive collection of artificial satellites orbiting a star, capturing as much energy as possible to power the needs of the satellite.  Instead of capturing the energy and locally consuming it, this modified design would redirect the energy of the star towards the planet(s), that is being terraformed.  The means of redirecting this energy are fairly legion, and that is with our current understanding of physics.  The image below gives a really crude example of what that could look like. 

Option 1) simple mirrors:  the name says it all and is pretty straight forward, sunlight hits a specially designed mirror, light is bounced roughly in the direction of the planet. Crude but reasonable.

Option 2) solar power converters, the individual elements of the swarm have solar collectors and some class of light emitter, the satellites capture the energy of the star, the broad spectrum energy is converted into electricity, which then powers some class of laser that aims light at the planet, (said lasers could be mono-chromatic or produce a range of useful light frequencies.

Option 3) Quantum dots.  This idea is similar to Option 2 but more sci-fi.  Quantum dots are cool pieces of material science where the piece captures energy in one part of the electromagnetic spectrum and re-emits that energy at a different frequency, examples include transforming infrared rays into visible light.  (there would probably need to be some mirrors to redirect the light emitted by the quantum dots.

These 3 options are broad categories and only indicate my inferences on possible solutions, others will most likely emerge if this idea is given credence.  

Challenges to this concept are legion, first and foremost, manufacturing and distributing these proposed swarm satellites, followed by how does a civilization guarantee that the satellites they use to ensure that the whole planet doesn't fall back into an ice-age.  

Positives of implementing light directing swarm. 

Multi-planet terraforming:  there are already proposals by engineers and science fiction authors to place arrays of mirrors at the langrangian points of Venus, Earth, and Mars to modify the quantity of solar radiation reaching these bodies with the hopes of regulating climates.  With a fully established swarm of satellites, a civilization bordering on Type 2 classification would have the ability to simultaneously regulate the climates of several worlds as opposed to a new array for each planet that needed to be modified.

Interplanetary trade would be far more feasible with a swarm of light directing satellites.  Depending on the level of sophistication of the swarm a civilization could provide highways of concentrated solar radiation, powering fleets of spaceships propelled by solar sails.

The planning required to produce this kind of swarm would be incredible, realistically building something as mind boggingly massive as a proper Dyson swarm would take centuries, but the benefits to the descendants of those who planned so far into the future would be tremendous.

Another thought before I go.  The nature of this kind of swarm, as opposed to more all encompassing proposals for modifying a star system, would ideally minimally impact the orbital plane that most planets find.  For researchers looking from Earth, I believe we would see the solar radiation of the star heavily modified, appearing compressed with semi-regular modifications to outputs that correspond to planetary orbits.  (honestly I'm talking out my ass here)

Edit 9/25/15:  I really should have re-read the Dyson Sphere entry on Wikipedia, in it they describe a range of designs, and consequently this entry is more of an example of a sub-category of development, that being said I still like the idea.

Mobus Bridge: A(n) (Im)Possible City in the Sky

Mobius Bridge is a mega-construction structure for the 31st century, built above the Earth's equator Mobius Bridge would be ring structure serving as a habitat platform.  Unlike many space rings proposed in science fiction works like Larry Niven's Ringworld the Mobius Bridge would not use centripetal force to provide the source of gravity, instead the Earth's gravity well would provide the attraction force.  For the Earth to provide the pull of gravity more naturally to the body of the Mobius Bridge, the structure of the Bridge would need to orbit around the Earth with the same angular velocity as the Earth's natural rotation.

What the the Orbital Rings might look like
Source: http://io9.com/if-earth-had-a-ring-like-saturn-508750253

Traditional approaches to placing objects in Earth Orbit would make it impossible for a space based structure to provide a gravity force not provided by some kind of additional acceleration put on a selected object.  The design of the Mobius Bridge would require some unique solutions to keep the ring structure both in orbit and having objects placed on the Bridge still feeling the downward tug of gravity.  Several potential solutions could be considered for keeping the Bridge suspended.  The first potential solution considered would involve using a collection of tethers linking up with counterweights, similar to the solutions suggested for building a space elevator.

        For a sufficiently low mass bridge designs a massive collection of thrusters would provide the necessary counter forces to keep the Bridge in orbit.  Unfortunately by the time the station got big enough to allow for a proper habitat the energy requirements to keep it suspended in space would only make sense for a species with near god like levels of energy production and control.  The most likely solution for keeping the Mobius Bridge in orbit would be to have the structure be made from two primary components.  The habitat segments of the Bridge would lazily drift over the Earth's equator maintaining the same day night cycle as the ground below.  Within the frame of the habitat would be one or more massive magnetic orbiting rings.  Each of these orbiting rings would serve as a track-way for the habitat structure to ride on, similar to magnetic levitation trains here on Earth.  The dynamic interaction of the forces between the inner rings and the habitat ring create a situation where the net balance leaves residents of the habitat ring experiencing the slightly reduced pull of the Earth's gravity, several hundred kilometers above the ground.

Roughly speaking the force of gravity on the Bridge would be a result of the tangential velocity of the ring and  its distance from the center of the Earth.  (for those who aren't power nerds, this means you are accounting for the tendency of objects being spun to pull outwards and that the force of gravity gets weaker at a distance)  To make the calculations easier, the primary sources of accelerations can be separated into two primary equations.  The biggest impact on the gravity felt by objects in the habitat ring of the Bridge would be the distance between the bridge and the Earth.  The force of gravity between two objects can be calculated using Newton's Law of Universal Gravitation, (see Fig 1)

Figure 1:  Newton's Law of Universal Gravitation

In this equation the variables are defined as follows

Figure 1A

F is the force of gravitational attraction.
G sub c is the gravitational constant (Fig 1A).
M1 and M2 are the respective masses of the objects                                                     being analyzed.
r is the distance between the center of mass of the objects

               While the above form is the most universal form of the Law of Gravitation for cases where M1 is much larger than M2 a slightly different version is used, where only the mass of the major body really needs to be considered.

Figure 2:  Acceleration of Gravity Near the Surface of a large body

Where g represents the rate of acceleration between the two objects, Gsubc is still the same and MEarth is the mass of the Earth, which is roughly 5.9736E+24kg and r represents the distance from the center of mass of the Earth to the center of mass to the object.  On the surface of the Earth r averages roughly 6370 km, for the Mobius Bridge that value will most likely fall between 6500 km and 6900+ kilometers from the Earth's center.

For the station being built at 130 km above the Earth's surface, or just 30 km above the line that defines what is legally space, the force of gravity would work out to be roughly 9.44 m/s^2.  At 530 km above the average surface of the Earth, gravity would still be an acceptable 8.37 m/s^2.   (note that these values don't yet factor in the centripetal force)

The second major influencing variable for determining the acceleration of gravity on objects on the Mobius bridge is the centripetal force caused by station rotating with the same angular velocity as the ground below. 

The relation of centripetal force to net acceleration would be a negative resultant of the equation 

Figure 3:  Acceleration of Gravity at the Equator
Reference:  Western Washington University

ω^2*r.  Where ω is equal to to the angular velocity of the planet Earth.  The value of is ω equal to 2*π/1day or 2*π/86,400s.  Putting all of these variables back into a single equation we get the equation to the right.  Using this equation we can create a rather useful table (Fig 4) on how much acceleration would be felt at different target orbits.  (A curve showing the estimated gravitational force at various altitudes will be found further down, useful detail the platform would experience roughly 0.5 g's around 2600 km above the Earth's surface)

Figure 4:  Force of gravity at 130, 330, 530, and 1000 km above the Earth

             Another consideration for making the Mobius Bridge would the trade off of habitable surface area vs how much of the sky would be blocked out by the station.  Making the Bridge too large would cause tremendous environmental impacts, affecting the amount of sunlight reaching plants, migratory patterns of regional fauna, and more.  To limit the impact of building a Mobius Bridge around the Earth, engineers would need to determine how much of the sun and moon could conceivably be blocked by the structure  before being problematic.  According to these sources NASA and Wikipedia the Sun and Moon are both roughly 0.5 degrees or 1800 arc seconds across from the perspective of an Earth bound observer (the decision to use angles allows for consideration of the perceived size of objects with respect to a terrestrial observer as opposed to the absolute size which will be constrained the most by this).  As this document deals with estimated values, we will roughly constrain the relative width of the station to between 1/100th and 1/10th the angular diameter of the Sun and Moon (between 0.005 and 0.05 degrees across).

Courtesy of Wikipedia.com: Angular Diameter

Fig 5 A geometric representation of the angular diameter
Courtesy of Wikipedia.com: Angular Diameter 

where d is the actual width of a selected object and D is the distance between the observer and the body and δ is the resultant angle. (see Fig 5)

Ex:  If engineers decide that they want to make a station that keeps its inhabitants at roughly 0.9 g's they would need to build it at an altitude of about 330km.  (See Fig 4) at that altitude and with the given constraints of keeping the station from not blocking the Sun excessively we get the equation shown in Fig 6

Fig 6 Angular Diameter with constraints

Solving for d @ D=330km we get the range 28.77m < d < 287.7 m

The final design would need to be a careful balance between the width constraints required for ecologically sustainable properties, maximizing internal working space, and a host of other variables.  One fortunate trait of the Mobius Bridge is that you are not limited to making a single structure around a planet, given enough time and patience by an advanced civilization a planet might be found with a collection of archologies that would rival the ring's of Saturn in beauty.

Follow Up Materials
One additional means of maintaining the operational altitude of the Mobius Bridge would be the use of electromagnetic tethers as a means of using the Earth's magnetic field to gently counter the pull of gravity and compensate for uneven mass distribution, both within the archology and the outside universe.  These tethers work by utilizing the Lorentz Force within the Earth's magnetic field. (I will try to add a less physics cut and paste explanation, once I understand this enough to do so)

Figure X  G force curve with respect to altitude (in meters)

Disclaimer Bit
It turns out the idea for building a Mobius Bridge was suggested at least as early as the 1870's by many geek's favorite inventors Nikola Tesla.  Wikipedia has a cool entry on Orbital Rings that provides a host of additional details.  A group called the Alna Space Program seems to have done an incredible amount of research into the design requirements of building an Orbital Ring, but I think I'm still going to call it a Mobius Bridge (seems sexier)  The author/engineer Paul Birch published a paper in the 80's into creating an orbital ring and other dependent structures, including a lightsail wind mill, and an orbital sphere built around a planet.
Other outlandish engineering proposals can be found on the Wikipedia entry for Megastructures, although something as large as the Mobius Bridge, you might as well go grandiose and call it a giga-structure.  Developing an orbital ring platform for planets like Venus could be integral in long term attempts to terraform the planet.

Other Stuff
Using the Lorentz Force for crazy orbits 
Further Reading on Tether Propulsion

Death Star Math: Return(ing) with a (possible) Solution

Solving the greatest (well maybe not but definitely one of its less sexy issues) engineering problem of science fiction, managing the surplus heat produced by all of the fanciful technologies imagined in far off worlds. 

When doing the math for the Death Stars exhaust port calculations it started to become more and more apparent* that if any civilization was developing warp drives, planet destroying super lasers, matter to energy converting teleportation platforms, and other crazy innovations that I would love to see during my life time, they would also need to be developing a way to keep these systems within some kind of operation temperature.  Previous entries on this blog on system cooling have hopefully created a rather deep explanation as to why heat management is such an issue in building your technological wonder, unfortunately for we hard science buffs, there isn’t much of a solution when it comes to applying traditional 3 spatial dimension based mathematics to radiative cooling.  Hopefully nerdier readers will most likely have latched on to the concept of using 3 spatial dimensions and started to ask themselves what I might be suggesting.  Right now I would ask those who saw this idea as critical, to take 5 seconds to imagine what solution I am inferring in the previous statement.

Anyone who honestly clued in and said to themselves “Hey, couldn’t you just add a new dimension for the heat to go out into” or something of that overall gist, please leave a comment bragging about this and I will happily add two points into your arbitrary cosmic score card that I have running in the back of my mind for most of humanity (not really).  Those of you who have come up with an alternative solution that you think makes even more sense or less sense really, I look forward to seeing your suggestions as well (if anyone ever reads this), also if you could make it a workable solution for cooling technologies like the transporters in Star Trek, I would be eternally grateful.    

Back to mathing.  The physics of black body emissions as a means of maintaining thermal equilibrium have been rather established with work starting with Ben Franklin (or earlier really I don’t know the history of physics that well).  Under our paradigms in physics a surface will transfer heat based upon the properties defined in the Stefan-Boltzmann Law, where the exposed area of the surface will emit some percentage of an ideal body’s energy flux, as a dependent on the relationship of the temperature of the objects surface to the ambient environment with both of those values raised to the fourth power. 

Within the physics of narratives like Star Trek, Star Wars, Babylon 5 etc… we are told that advanced species have discovered additional dimensions that are used for transport and communication.   For a power nerd like me, these additional dimensions seem like a perfect place to dump all of our spaceship’s surplus heat.

Long before Darth Sideous asked his various minions to begin developing designs for the Death Star, or before Captain.  James. T. Kirk seduced his way across the galaxy.  Some rather bright scientists and engineers got together and developed a technology that would allow them to make a radiator that cools 4 dimensionally.  No longer would only the exposed surface of your vessel be your only means of keeping your reactors operational.  These innovators created a solution that would allow each individual atomic layer of the cooling system to dump heat into a fourth spatial dimension and they would do it all with a really contrived acronym.  A smooth cube, one meter on a side, would go from having an exposed surface area of 6 sq m to 5.97E09 sq m of radiative surface area (this is actually a minimal estimate as I’m not super-duper certain as to how many liberties I can take with estimations.)  While not an exact comparison for various reason, one rather contrived analogy is saying that it would be like going from riding a horse from point a to b to traveling at the speed of light.  Additionally it is discovered that the scientists have found that subspace or hyperspace, whatever this fourth spatial dimension is called, is roughly as cold as the vacuum of space in the majority of our universe.  This critical property will allow you to reduce the heat transfer equation to the following.

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As I mentioned earlier the area of the radiator is where the math gets the fuzziest, the estimated value of 5.97E09 square meters per cubic meter was calculated by finding the inter-planar spacing of graphene on Wikipedia, listed as 0.335 nm or 3.35E-10m.  Graphene was chosen because it is awesome and for how arbitrary calculations are here it worked for me.  The cube can then be thought of as 2.985E09 individual atom thick layers capable of radiating their waste heat into the fourth dimension.  Each layer is somehow able to simultaneously transfer energy between layers and emit energy from both sides, a trait of the fourth dimensional special phsysics.  It should be noted, that by my logic it might make “more sense” to treat each individual atom as a four dimensional radiator and/or eliminate the concept of treating the radiator as a solid system, why not a 4D cooling plasma, and to that I say, I’m already spending too much time on theoreticals and not enough finding work (I wish it was otherwise).  Anyways all of this logic adds up to us creating a new function for balancing out the requirements of the cooling system.  Depending on how the variables are solved you then plug them back into the unit conversion shown below.

 

In the case of the super radiator material developed by the Death Star Development teams, one capable of operating at 20,000K and as a perfect black body.  The Death Star would also need to be at least      99.9999975563% efficient as a system for the radiator to fit within the exterior envelope of the Battle Station as in both have an estimated volume of 2.1447E+15 cubic meters. (before the theoretical detractor says that if I’m putting the radiators magic into a 4^th spatial dimension why should I even worry about its volume and to that I simply say, “eh, it shows scale and system complexity”) At 99.9999999% efficiency the radiator system would be about 4% of the volume of the non-moon.  I hope that someone found this interesting.