These are organizations that span that gray area between civilian law enforcement and the military. Much like the US Coast Guard. The Coast Guard is not a purely military force like the Navy, nor is it a civilian law enforcement agency like a transportation police. It performs some customs and security duties, but also does search and rescue functions plus environmental protection.
Outer space equivalent of terrestrial air traffic controllers. Monitors and controls the flight plans of local spacecraft. Generally only needed in "crowded" areas, such as the orbital space around inhabited planets.
This is more or less the space-going version of the Coast Guard. They are not military so much as they are a cross between a law enforcement agency and a search and rescue body.
Since the Coast Guard operates in the coast, the Orbit Guard operates within the Hill Sphere of inhabited planets.
Though the question of territory is a bit unsettled. A boat in the coast of Great Britain is stationary around Britain. But an orbital spacecraft constantly moves in its orbit around Terra, passing over many different continental nations on its ground-track. This isn't a problem if the entire planet is under one government, only if it is balkanized.
There is no hard and fast division between the Orbit Guard and the Patrol. They sort of blur into each other. In some cases they might merge into one organization. The Orbit Guard is more biased to the civilian/search-and-rescue end of the spectrum, while the Patrol is biased more to the military/pirate-hunting end of the spectrum.
Yes, I originally used the term "Orbit Guard" for those tasked with preventing asteroid bombardment warfare. I changed it for reasons explained here.
Orbital Patrol Ship Stats Propulsion Chemical
Exhaust Velocity 4,400 m/s Specific Impulse 449 s Thrust 3.5×106 N Thrust Power 7.7 gigawatts Total ΔV 6,100 m/s Mass Budget Engine Mass 7 mton Heat Shield Mass 15 mton
(15% re-entry mass)
(5% landing mass)
(5% landing mass)
(20% dry mass)
(5% dry m)
Tankage body 18 mton
INERT MASS 75 mton Payload,
25 mton DRY MASS 100 mton Propellant
300 mton WET MASS 400 mton Mass Ratio 4.0 Plus
This is a splendid spacecraft designed by Rick Robinson, appearing on his must-read blog Rocketpunk Manifesto. This was designed for his Orbital Patrol service, which he covered in three previous posts.
The important insight he noted was that if you can somehow get your spacecraft into orbit with a full load of fuel/propellant, it turns out that most cis-Lunar and Mars missions have delta V requirements well within the ability of weak chemical rockets. So you make a small chemical rocket and lob it into orbit with a huge booster rocket (heavy lift launch stack). This will be the standard Orbit Patrol ship.
It can also be boosted into orbit by a smaller booster rocket, then using the patrol ship's engines for the second stage. So as not to cut into the ship's mission delta V, it will need access to an orbital propellant depot to refuel. At a rough guess, you'll need 9,700 m/s delta V to boost the patrol ship into orbit (7,900 m/s orbital velocity plus gravity and aerodynamic drag losses). So the booster will need 9,700 m/s with a payload of 400 metric tons. Bonus points if the booster is reusable.
Actually, it reminds me a bit of the old Three Man Space Scout.
At a rough guess, Rick figures that if the ship is capsule shaped it will be about 12 meters high by 14 meters in diameter. If it is wedge shaped, it will be about 40 meters high by 25 meters wide by 8 meters deep.
In both cases, total interior volume of 1,200 m3 (of which 900 m3 is propellant), and a surface area of 800 m2
Present day expandable propellant tanks have a mass of about 6% of the mass of the liquid propellant. Rick is assuming that in the future the 6% figure will apply to reusable tanks as well.
If my slide rule is not lying to me, the 300 metric tons of H2-O2 fuel/propellant represents 33.3 metric tons of liquid hydrogen and 266.7 metric tons of liquid oxygen. About 470 m3 of liquid hydrogen volume (sphere with radius of 4.8 m) and 234 m3 of liquid oxygen volume (sphere with radius of 3.8 m). This is a total volume of 704 m3 which falls short of Rick's estimate of 900 m3 so I probably made a mistake somewhere.
Landing on Terra will use retro-rockets, the heat shield for aerocapture, maybe a parachute, and aircraft style landing gear for belly landing. Landing on Luna or Mars will be by tail-landing on rear mounted landing legs. That will also mean reserving some of the propellant for landing purposes.
Note that the heat shield is rated for the ship's unfueled mass (heat shield mass = 15% of ship's re-entry mass), there is not enough to brake the ship if it has propellant left. This assumes a "low-high'low" mission profile: start at LEO, go outward to perform mission while burning most of the propellant, then return to LEO or even land on Terra. So 15 metric tons for heat shield is for a ship with a mass of 100 metric tons at re-entry (ship's total dry mass).
If the ship is going to aerobrake then return to higher orbit, it will need more heat shield mass to handle the extra mass of get-home propellant. This will savagely cut into the payload mass, which is only 25 metric tons at best. For example, if the mission had the ship heading for translunar space from LEO after aerobraking, the extra propellant mass at aerobrake time will increase the heat shield mass from 15 metric tons to 31. This will reduce the payload from 25 metric tons to 8. But by the same token a ship that will not perform any aerobraking can omit the heat shield entirely, using the extra 15 metric tons for more propellant or payload.
Payload includes habitat module (if any) as well as cargo, since hab modules are optional for short missions. The gross payload is 25 metric tons, of which 20 is cargo and the other 5 mtons are payload bay structure and fittings. If you assume two tons of life support consumables per crew per two week mission; then the ship could carry a crew of five plus 12 mtons of removable payload, or a crew of 10 and 4 mtons of payload (the more that payload is consumables, the less mass needed for payload bay structure).
Patrol Missions Mission Delta V Low earth orbit (LEO) to geosynch and return 5700 m/s powered
(plus 2500 m/s aerobraking)
LEO to lunar surface (one way) 5500 m/s
LEO to lunar L4/L5 and return
4800 m/s powered
(plus 3200 m/s aerobraking)
LEO to low lunar orbit and return 4600 m/s powered
(plus 3200 m/s aerobraking)
Geosynch to low lunar orbit and return
Lunar orbit to lunar surface and return 3200 m/s
LEO inclination change by 40 deg
LEO to circle the Moon and return retrograde
3200 m/s powered
(plus 3200 m/s aerobraking)
Mars surface to Deimos (one way) 6000 m/s
LEO to low Mars orbit (LMO) and return 6100 m/s powered
(plus 5500 m/s aerobraking)
Representative samples of small space craft atop booster rockets:
All that junk in Terra orbit could trigger the dreaded Kessler Syndrome. If it happens, mankind might be cut off from space for generations. The Orbital Debris Collection agency is tasked with preventing that unhappy state of affairs.
The Kessler syndrome (aka Kessler Effect, Collisional Cascading, or Ablation Cascade) is where the number of pieces of orbiting space trash becomes so high that a single collision can start a chain reaction. A collision turns two pieces of trash into twenty. Most of those twenty new pieces will suffer collisions, now you have 400. When those hit you'll have 8,000. A couple of more collision cycles and LEO will basically become impassable. No more space launches, no more astronauts, no more GPS, no more communication satellites, no more space station.
If it actually happens space exploration and even the use of satellites could be rendered impossible for many generations. Egads.
The cascade may not spread to geostationary orbit, but that will just slightly delay matters. As those satellites wear out, they cannot be replaced.
A fictionalized version of this was depicted in the movie Gravity. It was exaggerated for dramatic effect, but not by much.
Note that this will probably be only an issue in Terra (or alien homeworld) orbit for hundreds of years to come. Other planets will need that long before enough trash collects in their orbit to become a problem.
Since the Kessler Syndrome could deny access to space for generations, it is logical to establish a (preferably multinational) organization charged with cleaning up orbital debris. But never underestimate the power of human stupidity.
Since politicians in general care little for anything happening beyond the next election cycle, they probably have little appetite for the money and poltical capital which must be spent to establish such an organization. Much like Spaceguard, actually. Action will probably be triggered by a close call or two.
And much like the manga Planetes the members of the serivce will be denigrated as "janitors" and "trash collectors".
Maybe after a partial Kessler the people (and corporations who suffer savage losses to their quarterly profits) will wake up and push for an orbital debris collection agency with teeth. Nations who recklessly launch rockets into risky trajectories will be hit with punishing sanctions. Or hit with an ODC commando team capturing the launch facilities.
And terrorists attempting to initiate a Kessler event will be a top-priority item with the counter-terrorism agencies of the world's nations. Classification: Hostis humani generis (Latin for "enemy of mankind"). Planetes had the The Space Defense Front, a terrorist organization that believes mankind is exploiting space without first curing global problems such as mass famine and the widened socio-economic divide on Earth.
There is no hard and fast division between the Orbit Guard and the Patrol. They sort of blur into each other. In some cases they might merge into one organization. The Orbit Guard is more biased to the civilian/search-and-rescue end of the spectrum, while the Patrol is biased more to the military/pirate-hunting end of the spectrum.
In the realm of science fiction, the Patrol was created by many authors. But the most well developed was in the space operas of Andre Norton. Norton's Patrol is right in the gray area between civilian and military, a combination of the police and the space navy. They appear in Star Rangers, the Jern Murdoc series, Star Hunter, and the Solar Queen series.
I wasn't sure how to logically justify such an organization, but Rob Garitta has a brilliant solution in his essay below:
Yes, they will sometimes have to do naval boarding in the discharge of their duties.
Payload Crew 25 Hab Module 100 tons Consumables 25 tons Other Payload 75 tons Total Payload 200 tons Propulsion Bus Engine+Radiator 200 tons Tankages+Keel 100 tons Stats Dry Mass 475 tons Loaded Mass 500 tons Propellant Mass 500 tons Wet Mass 1000 tons
The discussion thread about 'Industrial Scale of Space' veered, among other things, into a discussion of patrol missions in space. My first reaction was that (so long as you aren't dealing with an interstellar setting) there is no place in space for wartime patrol missions. But the matter might be more complicated, and for story purposes probably should be.
According to The Free Dictionary, patrol is The act of moving about an area especially by an authorized and trained person or group, for purposes of observation, inspection, or security. This fits my own sense of the word, and is in fact a bit broader, 'security' including SSBN patrols, which are not observing or inspecting anything, just waiting for a launch order if it comes.
In a reductionist way you could say that all military spacecraft are on patrol, since they are all on orbit, and if they are orbiting a planet they have a very regular 'patrol area.' But this is not what most of us have in mind. We picture a patrol making a sweep through an area, looking for anything unusual, ready to engage any enemy they encounter, or report it and shadow it if they cannot engage it.
Back in the rocketpunk era it was plausible that, say, Earth might send a patrol past Ceres to see if the Martians had established a secret base there. But (alas!) telescopes 'patrolling' from Earth orbit can easily observe the large scale logistics traffic involved in establishing a base; watch it depart Mars and track it to Ceres. If you want a closer look you can send a robotic spy probe. If you engage in 'reconnaissance in force' by attacking Ceres, that is a task force, not a patrol.
In an all out interplanetary war there may be plenty of uncertainty on both sides, but very little of it can be resolved by sending out patrols.
But of course all-out war is not the context in which the Space Patrol became familiar. I associate it with Heinlein's Patrol; apparently the 1950s TV series had an independent origin (unlike Tom Corbett, who was Heinlein's unacknowledged literary child).
The rocketpunk-era Patrol, which in turn gave us Starfleet, was placed in the distinctly midcentury future setting of a Federation. This is as zeerust as monorails. But plausible patrolling is not confined to Federation settings. It can justified in practically any situation but all out war.
Orbital patrol in Earth orbital space will surely be the first space patrol, and could be imagined in this century. It might initially be a general emergency response force, because travel times in Earth orbital space are short enough for classical rescue missions. On the interplanetary scale, with travel times of weeks or more likely months, rescue is rarely possible. But eventually power players will want some kind of police presence or flag showing in deep space.
As so often in these discussions, I picture a complex and ambiguous environment in which policing, diplomacy, and sometimes low level conflict blur together. To take again our Earth-Mars-Ceres example, there are kinds of reconnaissance that cannot be carried out by robots (short of high level AIs). If Ceres closes its airlocks to liberty parties from a visiting Earth patrol ship, that conveys some important intelligence information.
The ships that perform these missions will be fairly large (and expensive). They must carry a hab pod providing prolonged life support for a significant crew: at least a commander and staff, SWAT team of espatiers, and some support for both.
Let us say a crew of 25—which is cutting the human presence very fine. Now we can venture a mass estimate. Allow 100 tons for the hab compartment plus 25 tons for crew and stores plus 75 tons other payload, for a total payload of 200 tons. Let the drive bus be 200 tons for the drive, including radiators, and 100 tons for tankage, keel, and sundry equipment.
Our patrol ship with a crew of 25 thus has a dry mass of 475 tons, mass fully equipped 500 tons, plus 500 tons propellant for a full load departure mass of 1000 tons. Cost by my usual rule of thumb is equivalent to $500 million, perhaps $1 billion after milspecking, expensive compared to military planes, cheaper than major naval combatants.
This is no small ship. If the propellant is liquid hydrogen the tanks have a volume of about 7000 cubic meters, equivalent to a 7000 ton submarine. The payload section is about two thirds the mass of the ISS and of roughly comparable size, though the hab is probably spun giving the prolonged missions.
Armament is necessarily modest. The 75 tons of additional payload allowance probably must include a ferry craft for the espatiers and an escort gunship or two, plus their service pod, leaving perhaps 15-20 tons each for kinetics and a laser installation. The laser might be good for 20 megawatts beam power, with plug power from the 200 megawatt drive engine.
This ship is no laser star, but the laser is respectable. Assuming a modest 5 meter main mirror and a near IR wavelength of 1000 nanometers, at a range of 1000 km it can burn through Super Nano Carbon Stuff at rather more than 1 centimeter of per second. Its armament is also rather 'balanced.' My model shows that this laser can just defeat a wave of about 1000 target seekers, each with a mass of 20 kg, closing at 10 km/s—thus a total mass of 20 tons, comparable to its kinetics payload allowance.
Deploying troops, or personnel in general, is impressively expensive: About three fourths of the payload and cost of a billion dollar ship goes to support and equip a crew of 25, with perhaps a dozen espatiers. For comparison the USS Makin Island (LHD-8) displaces 41,000 tons full load, carries a crew of 1200 plus 1700 Marines, and costs about $1.8. So by my model it costs about as much to deploy one espatier as 80 marines.
And this ship is about the minimum patrol package, so standing interplanetary patrol is a costly and somewhat granular business, something not everyone can afford.
Rocketpunk Patrol Ship
Dry Mass 76.2 metric tons Wet Mass 384.6 metric tons Mass Ratio 5 Length Z 73 meters Length Y 20.1 meters Length X 15.2 meters Engine x2 F-26-A LH/LOX Thrust 7.7×106 N Acceleration 0.5 g ΔV 8,200 m/s
This is the same one from the other day, only dressed up with a nice logo and some stats. These are realistic capabilities made courtesy of the charts and other information available from Atomic Rocket and inspiration from Rick Robinson's Rocketpunk Manifesto.
My PL differs from the one in Rick Robinson's article in a few key areas. The main difference is that it is not made for long hauls. It only has a delta v of about 8200 m/s. This will not get one far in the solar system but it allows a forward deployed Patrol Craft a sufficient "range" to perform many of the missions we discussed in the last post on Building a Space Navy. Our little A-Class has enough Delta V to shape a light-second orbit around a convoy in deep space, conduct SAR missions anywhere in cis-lunar space, or to reach any moon of Saturn from any other moon. Obviously, this rocket is mostly propellant (mass ratio 5). If you drew lines through the side view of the rocket that bracket the docking rings, you would encompass the entire pressurized volume. I've got to say, it's nice to work on a warship for a change — I don't have to make it economical to run!
One of the interesting things about this design is actually the freedom the little carried craft gives me. It was a throw-away touch, originally — a design borrowed from another project. But as I got to looking at the little thing, I realized that it's about the size of the Saturn V stage/Apollo/LM stack. That means it should be able to go from Earth Departure to Lunar orbit. That means that it has the Delta V to ferry crew to and from a Patrol Craft on station away from the convoy. That means, like submarines, our Patrol Craft can have two crews and stay out for a lot longer than otherwise. This is one of those realistic touches that I hope add to the charm of the rocket's design.
ed note: a 1500 nanometer near infrared laser with a 10 meter fixed mirror can have a 4 centimeter spot size out to 220 kilometers or so. A 4 meter mirror can have a 4 centimeter spot size out to 87 kilometers or so.
Mass drivers and other rockets can be used to alter the orbits of asteroids (and mass drivers can use rocks from the asteroid itself as a built-in source of propellant). Popular with asteroid miners who want to nudge their claims into different orbits. Unpopular with the astromilitary of all nations, who think that civilization-destroying asteroid bombardment is not a power one wants to give to rock-rats.
The "Dinosaur-killer" asteroid was probably about 10 kilometers in diameter, and it caused a freaking mass extinction of three-quarters of plant and animal species on Terra. There are approximately ten thousand asteroids in the belt of size 10 km or larger. And of course there are much more than ten thousand "fun-sized" asteroids, not large enough to wipe out civilization on Terra, but big enough to obliterate a nation that you dislike. Space faring nations with asteroid moving technology will look at the list of small asteroids, look at the list of nations hostile to them, and start to get ideas.
If asteroid moving technology is cheap enough it won't be a game just for nations, you might find mere corporations and James Bond villains getting into the act.
Once asteroid-moving technology is available, one can foresee a branch of "spaceguards" in each astromilitary, patrolling the solar system to prevent unauthorized changes in asteroid orbits. Any rock-rat, corporation, or nation that wishes to move an asteroid will have to file a proposed trajectory and request a permit from the Spaceguard.
(ed note: Originally I called this branch the "Orbit Guard." I have gone to the trouble to change the name for two reasons:
 The term Spaceguard is already being used for this function.
 The term "orbit guard" is a much better fit for the space-going version of the Coast Guard.
I regret any inconvenience this has caused.)
The Guard would keep a close watch on all asteroids. If one starts to move without a permit, or if one with a permit strays off the filed flight plan, military spacecraft of the various space faring nations will pounce and blow the snot out of it. Spaceguard ships will be armed, since the evil asteroid movers will probably shoot back. Of course prior to that the evil asteroid movers will have all their crew and equipment scrubbed of anything identifying the nation behind this heinous act, since it easily fits into the category "act of war", or even "genocide."
Probably there will be a branch of spaceguards in all of the space faring nations. They will not just watch asteroids, they will also keep a close eye on the spaceguards belonging to other nations, just to keep them honest. If nation X has a spaceguard, enemy nation Y will want their own spaceguard as well. Otherwise nation X might be tempted to turn a blind eye to somebody targeting nation Y's capital city with an errant asteroid.
Requests for asteroid moving permits will have to be filed with the Spaceguards of all nations. Things might get a bit political here, since giving all the Spaceguards veto power can be abused. Say, if nation X was currently angry with nation Y, nation X might pressure their Spaceguard to automatically veto any asteroid moving requests from nation Y using specious reasons. Some kind of appeals process will have to be available.
And who knows? Spaceguard might actually find an errant asteroid that just happened to be naturally on collision course with Terra, instead of uncovering a Sinister Plot by Dr. Evil. It will be real nice to have the spaceguards there to bump it off course. Just ask the dinosaurs. Oh, that's right, you can't because an asteroid made them all go extinct.
Arthur C. Clarke invented an asteroid early warning system called "Project Spaceguard" for his novel Rendezvous with Rama in 1972. Clarke was most gratified when a real live Spaceguard was created in 1992 (duely giving Clarke credit for the name). David Levy stated in an interview "The giggle factor disappeared after Shoemaker-Levy 9." After the impact of Comet Shoemaker-Levy 9, asteroid detection programs all over the world abruptly received greater funding.
The main point is it is quite easy to nudge an asteroid off collision course if you have a few decades of lead time. If you only have a few days notice you are going to have to use nukes. So start discovering and surveying all those Near-Earth objects right now.
Getting a Spaceguard system set up is going to be tricky. Quis custodiet ipsos custodes? and all that.
Before spaceguards with space ships are established as a branch of the military, any civilian attempts at asteroid re-direction will have to be accompanied by a division of army solders. From several nations. Every propulsion event will have to have the math checked by military astrogators. Of each nation. And the execution of the propulsion events will be closely monitored. At gun point. Of each nation.
Don't forget the army fire-teams tasked with aiming their weapons at each of the foreign army divisions, just in case they try pulling a fast one. Don't drop an incandescent light-bulb or otherwise make a noise sounding like a rife-shot. Otherwise when the firing stops everybody will be dead and the room will look like a colander.
It is probably a requirement to have several nations establish spaceguards with space ships, since a single nation with a monopoly on orbit guards is dangerous. Not just that the owning nation might issue covert orders to "accidentally" drop an asteroid on hostile nation Y. There is also the danger that a spaceguard ship might revolt, be infiltrated by terrorists, be composed of enemy sleeper agents, snap under the pressure and go insane, be part of a military coup conspiracy, or otherwise turn rogue and drop an unauthorized rock on some nation. Including the owning nation.
If there are spaceguard ships from other nations constantly watching your spaceguard suspiciously, it becomes much more difficult for a ship to go rogue. It is much safer to have several nations with spaceguards.
Perhaps it would make sense to have something like the Two-Man Rule used in nuclear launch protocol. Spaceguard ships of a given nation would go in pairs, watching each other. Or in triples, in case one ship becomes disabled. You see how the complexity quickly snowballs.
However the Two-Man Rule was designed to prevent something from happening, not to ensure something happens. If Spaceguard ships Alfa and Bravo are near an asteroid, and Bravo turns rogue and tries to push the asteroid so it obliterates Terra, then according to the safeguard of the Two-Man Rule ship Alfa will shoot the ever-living snot out of ship Bravo. Everything is fine.
What is not so fine is if ships Alfa and Bravo are trying to save Terra by redirecting an asteroid aimed by Dr. Evil. Ship Alfa can start the redirection process, only to get the ever-living snot shot out of it by the subverted Ship Bravo. In this case the Two-Man Rule fails to ensure the desired result happens.
The spaceguard ships also might contain self-destruct devices, controlled by the owning government. Though you'd better be darn sure the enemy doesn't get its hands on the destruct codes. Or you will be really angry when your entire spaceguard fleet goes poof!
However, a spaceguard can still be used for nefarious purposes, such as making an excuse to annex the Asteroid miners.
A separate but closely related duty performed by the Spaceguard is that of range safety officer. If civilian ships can be used as weapons of mass destruction, in an emergency the Spaceguard can trigger the civy ship's self destruct device. Spaceguard shares this responsibility with the Launch Guard. Generally the Launch Guard's range safety keep watch around spaceport launch sites while Spaceguard's range safety officers keeps watch everywhere else. As far as Spaceguard is concerned, a civilian spacecraft on collision course with a colony is the functional equivalent of a rogue asteroid. Only of artificial origin and hopefully already equipped with a handy self destruct.
Spaceguard spacecraft will probably have the following equipment:
The Spaceguard spacecraft will carry their own high thrust equipment in order to re-direct errant asteroids. A nasty government might aim a large rock at an enemy nation then destroy the mass driver they used. The Spaceguard cannot count on the equipment being available to redirect the asteroid. The equipment might also become damaged in the battle to clear the asteroid of hostiles, especially if the bad guys use the mass driver as an impromptu kinetic energy weapon. The Spaceguard will be forced to neutralize the mass driver, which is never good for its warranty.
Scott Lowther figures that Orion drive style nuclear pulse units would be perfect tools for a spaceguard to redirect asteroids. They are more or less designed for the task (spacecraft pusher plate, asteroid, what's the difference?), they are powerful, small enough that any sized spaceguard ship can carry a large number of them (about 0.6 meters tall by 0.36 meters in diameter), and are certainly far more portable than lugging a full sized mass driver. If you position the charges far enough, the tungsten propellant will spread its impact evenly over the asteroid's entire hemisphere. This helps ensure that the asteroid is just nudged off course, not shattered into a deadly charge of cosmic buckshot still aimed at Terra.
The standard nuclear charge used in the USAF Orion report had a yield of one kiloton and would hit the asteroid with about 2.01 megaNewton-seconds of impulse. The Chelyabinsk meteor had a mass of about 10,000 metric tons. One USAF pulse unit would change its velocity by 0.2 meters per seconds. Doesn't sound like much but in the real world it's pretty good. So a single USAF charge could have made the Chelyabinsk meteor miss Terra by 100 kilometer if it was placed to detonate about six days before the meteor was scheduled to strike Terra. Or ten charges could make it miss by 100 kilometers if there was only 14 hours lead time prior to Terra impact.
If Spaceguard ships carrying Orion nuclear pulse units does not appeal to you, then perhaps the Spaceguard ships will have mass drivers as propulsion. And a large thrust bracing on the nose. After the resistance has been neutralized (i.e., all the evil asteroid movers have been blasted or are in custody) the Spaceguard ships will land on the asteroid, ship noses pressed into the aseroid's surface and the ship tails pointed skyward, deploy scoop conveyor belts to grab reaction mass, and start running their mass drivers at full bore.
Legitimate and illegitimate asteroid movers will probably have to make do with mass drivers instead of Orion pulse units. Most military forces are quite unreasonable about allowing nuclear devices into civilian hands. Evil asteroid movers might illegally use Orion units, but they will have to work quick. Multiple nuclear detonations will be visible all over the solar system and will quickly draw unwanted attention.
SpaceWorks Engineering did a study for NASA about deflecting killer asteroids on collision course with Terra. The concept they came up with is Modular Asteroid Deflection Mission Ejector Node (MADMEN) robots. They are unmanned, independently controlled, nuclear powered, and equipped with a powerful mass driver. The idea is to make a solution that is "scaleable". If the asteroid is larger, then send more MADMEN modules. Plus a few extras in case some of them suffer malfunctions.
A transfer vehicle delivers a MADMEN to the impactor asteroid. The MADMEN lands at the correct spot, the landing gear digs in to anchor the MADMEN, the heat radiator and mass driver unfurls, the reactor powers up, a drill head extend into the body of the asteroid to gobble rocks for mass driverpropellant, and the mass driver proceeds to lob the rocks at a rate of one per minute. If the asteroid is rapidly rotating, the MADMEN is intelligent enough to only fire a rock when the rotation brings the mass driver to point in the desired direction. The thrust of the mass drivers gradually alters the trajectory of the asteroid into a safe direction.
These would be useful to both Spaceguard and to evil asteroid movers. Spaceguard can station caches of MADMEN in strategic locations, without having to worry about life support for Guard crews (MADMEN are unmanned, remember?). Evil movers will not have to worry about Spaceguard capturing evil crews, who might be coerced into revealing which evil nation is responsible for the evil plot. MADMEN may also be easier for evil asteroid movers to secretly emplace on a lonely asteroid, but the onboard reactor and heat radiators will rapidly give away their positions once powered up.
|Baseline MADMEN lander parameters|
|Ejection Velocity||187 m/s|
|Ejecta mass per shot||2 kg|
|Mass driver length||10 m|
|Shot frequency||1 per minute|
|Total surface time of proces||60 days|
|Total power required||42.2 kW|
|Dry Mass||1,503 kg|
|Gross Mass||1,621 kg|
|Baseline mission parameters|
|Delta-V imparted to Killer Asteroid||0.2 m/s|
|Killer Asteroid Mass||2.7 × 109 kg|
|Killer Asteroid Diameter||130 m|
|Delta-V to get to Killer Asteroid||5,423 m/s|
|Dry Mass (with MADMEN payload)||2,207 kg|
|Gross Mass (with MADMEN payload)||8,816 kg|
Spaceguards in Science Fiction
The Launch Guard operates around spaceports, where launches occur (obviously).
At a spaceport, bulk cargoes can be launched with huge mass drivers. People and cargo can also be boosted into orbit using laser launch systems. Both of these can be used as ground-to-space weapons powerful enough for a planetary fortress. The Launch Guard controls these installations [a] to ensure terrorist do not use them as impromptu terrorist weapons of mass destruction and [b] to repurpose them as weapons of mass destruction to wreck death and destruction on any suddenly appearing invading enemy spacecraft.
If a spacecraft is on a collision course with something valuable or full of innocent bystanders (like the spaceport), or behaving erratically or suspiciously, the on-duty Launch Guard Range Safety officer will spring into action. They will trigger the off-course ship's integral self-destruct device or use surface-to-space weapons to blast it into smithereens. The range officer will have the agonizing task of weighing the lives on the ship with the lives at the projected impact point.
If civilian owned spacecraft have propulsion systems frightful enough to be weapons of mass destruction then by law all such ships will be equipped with destruct devices controlled by the launch guard. Just in case a tramp freighter with an antimatter engine has a drunk pilot and starts heading towards a major metropolitan area.
If the destructive energy is from the wayard ship's engine (e.g., antimatter) the self-destruct charge will just have to neutralize the engine. But if the destructive energy is the ship acting like an impromptu kinetic energy weapon, the closer the charge can come to vaporizing the entire ship the better.
Most real-world boosters and spacecraft include self destructs to prevent lawsuits and massive negative publicity if the rocket goes off course. Manned rockets generally have some sort of launch escape system to propel the habitat module clear of the blast radius (with the notable exception of the Space Shuttle).
The range safety officer with their finger on the big red button are usually located at some distance from the object they are blowing up. So they will have some objectivity (i.e., not hesitate because they are scared of committing suicide).
Huge solar power stations (SPS) can power MagBeams to push little spacecraft in near orbit or to give them a kick to another planet.
SPS can also power titanic laser arrays used for beam-powered propulsion for laser-thermal spacecraft all over the solar system. Especially since non-beam powered solar sails can only do about 3 milligees and you need at least 5 milligees to be practical.
They can also launch laser sail spacecraft on interstellar missions.
Such stations would be valuable and useful pieces of space infrastructure.
All of these provide advantage to people using spacecraft, but with the cost of being at the mercy of whoever owns the SPS. Ship captains have to file their flight plan with the SPS, and have to follow it to the letter or the beam cannot stay focused. And if your bill isn't paid up Beams-R-Us will pull the plug. Sure Beams-R-Us will need massive investments to construct the powersats and laser arrays, but it will be quite lucrative.
But then there is the awkward fact that a beam which could power a freighter in the asteroid belt is also powerful enough to vaporize a battleship in cis-lunar space. Not to mention that any space garbage scow could suddenly become a laser spitting death machine with only the support of a powersat and a few half-silvered mylar balloons used as laser combat mirrors. You will have Powersat Weapons. The military will not be happy...
...Unless the military owns and operates Beams-R-Us.
Naturally this can quickly turn into a Mutual Assured Destruction situation once there are more than one nation in the beam business. Which could sabotage efforts for the first beamsellars to get established. Solar power stations are such big targets and so very fragile. There might have to be an international treaty forcing three or more nations to build large solar-powered laser arrays simultaneously.
In Rocheworld by Dr. Robert E. Forward the military had a series of such laser stations around Mercury. Given the plentiful solar energy each station could crank out a laser beam that was about 1.3 terawatts.
In Larry Niven's "Known Space" series, the warlike alien Kzinti gleefully attack our solar system, knowing that the pacifistic humans had no quote "weapons" unquote. This disaster was called the Kzinti Lesson. Among other things the Kzinti discovered that even though terrawatt batteries of lasers used to push lightsail interstellar probes were technically "propulsion systems", nonetheless they could vaporize Kzinti warships like ants under a magnifying glass in the hot sun.
G. Harry Stine's (writing as Lee Correy) wrote a rocketpunk novel called Manna. In the novel, the military branches of the space-faring nations would like to put five gigawatt High Energy Laser (HEL) satellites in orbit. Using fancy techniques they are powerful enough to get their weapon laser beam through Terra's atmosphere and incinerate targets on the ground.
The trouble is the militaries want the HEL beamer satellites to be stealthy. The root of the trouble is that a five gigawatt HEL beamer containing a +five gigawatt power source is about as stealthy as a New York 4th of July fireworks display.
If only the power source could be at some distance from the HEL beamer, sending the energy by electromagnetic waves. You know, the same way a powersat sends microwave energy to ground power stations... hmmmmmmm.
That would work, the HEL beamers could be stealthy little dastards with no nuclear power plant, but rapidly unfurling a powersat reception antenna when it came time to zap something.
Now comes a bigger problem. Nobody can build any powerstats.
Why? Well, no corporation is going to embark upon a multi-billion dollar project like a powersat without insurance. And no insurance company is going to underwrite a multi-billion dollar installation which becomes a military target the instant it redirects its power beam from a power station in order to energize a HEL beamer. Especially a military target so huge, easy to hit, and incredibly fragile as a powersat.
How to solve the problem? Well, since it is an insurance problem, there should be an insurance solution.
Through a series of international agreements, the Resident Inspection Organization (RIO) was formed. This international group regularly inspected all powersats, and insured that they stayed pointed at ground power stations. In exchange, the insurance companies would underwrite the powerstats. If any powersat started to energize something that might be a stealthed HEL beamer, RIO would sound the alarm to all the astromilitaries, presumable giving the military units enough time to blow the living snot out of the powersat.
Naturally the astromilitary of Nation Alfa would be angry at RIO squealing when astromilitary Alfa tried to energize one of their HEL beamers. But astromilitary Alfa would be vary grateful if RIO squealed about astromilitary Bravo, Charlie, Delta or Echo doing the same thing.
If you are trying to establish a base or colony on a moon or other terrestrial body, you've got a problem. Such installations will require thousands if not millions of tons of pre-fab structures and support material. The tyranny of the rocket equation is going to make establishing the base more expensive than a mobster loan shark, because every gram counts.
This would be a perfect place to use in-situ resource utilization. But it is one thing to roast some gypsum to obtain some water. It is quite another to use local ores to create electronics and pressurized domes. Its not like there is a machine you can shovel dirt in one end and get habitat modules and stuff out the other.
Or is there?
Enter the Santa Claus Machine. You actually can shovel dirt in one end and get hab modules out the other. As long as all the chemical elements you need for the module can be found in the dirt. Such a machine will be priceless for creating planetary bases and spaceports.
But the trouble is such a machine can be a little too useful. It can make other stuff, like nuclear weapons, artillery lasers, unstoppable robot armies, and whatnot. Not to mention small items like undetectable counterfeit money. Heck, even the disassembler input stage is bad enough. It can quickly and easily turn tons of uranium ore into a lovely set of weapons-grade highly-enriched subcritical uranium ingots and a pile of waste uranium.
Blasted Santa Claus Machine is worse that a beam-propulsion array powered by a titanic solar power station. Unbelievably useful, but not the sort of thing you want in unsupervised civilian hands.
Well, lets use the same solution. Have them controlled by the military. Just like we have the Laser Guard in control of beam-propulsion arrays, we can have the Santa Guard in control of Santa Claus Machines. Also known as "Santa's Little Helpers."
So at the site of the proposed new base, the Santa Guard will emplace one or more Santa machines, and construct a secure housing where they can be kept under armed guard. The construction crew will submit blueprints to Santa Guard. The Santas will closely examine the blueprints to make sure they are not for weapons of mass destruction or other contraband, and supervise the printing. They will also be on the lookout for sub-units in several separate print runs that might be cleverly disguised components of a contraband item.
And in cases of illegal blueprints or illegal output, the Santas will do their best to arrest and bring to justice those who have broken the law.
Sovereign nations almost invariably impose controls on the import and export of trade goods (unless the nation is a freeport or something). The controls kick in when trade goods cross a magic line called the customs border. The border is patrolled by that branch of the civilian military called the Customs: collecting tariffs, halting or confiscating contraband, and apprehending smugglers.
If the custom border is located inside a spaceport, patrolling the boarder is the responsibility's of ground-based (or space station based) custom service. But if the custom border is drawn around the entire planet at orbital height, or even around an entire solar system / interstellar empire, then the job belongs to the space branch of the customs agency.
The primary difference is that the spacial branch has cutter-class spaceships, instead of wearing out shoe leather walking around the 'port.
Naturally the latter branch is a bit more … exciting. Ground custom agent's main excitement is seeing the ship's captain break out in a cold sweat when you discover something irregular. By contrast space custom agents never know when that innocuous blip on the radar screen might abruptly turn into a running gun-battle with a heavily armed smuggler spacecraft.
Ground customs also never know the gut-wrenching terror when a seemingly routine board-and-search operation turns deadly. Ground customs might not bother to carry sidearms, but space customs agents on a boarding mission invariably do. Otherwise they are just giving potential smugglers free hostages.
Ground customs agents just have to pound the pavement keeping an eye on the few openings in the spaceport's custom border. Space customs, on the other hand, may need to maintain constant deep space patrols of the huge border surrounding the planet/empire/whatever. The ease of the task depends upon the range and discrimination ability of the custom ship sensors.
The astronomical section will use telescopes or whatever to locate all the unexplored solar systems on the frontier. The scout section will send robot probes or manned expeditions to likely systems for a closer look at any planets that are possible colony sites. Sometimes a starship with a single person (called a "first-in scout") will to the initial once-over, and will tell Galactic Survey which planets are worthy of a full expedition.
The astronomical section can weed out some star systems unlikely to contain habitable planets. There are certain spectral classes of stars which are unlikely to to live long enough to nurture a habitable planet, others are unlikely to have any planets at all. The astro section can also spot the danger signs of indigenous intelligent alien species. That will be turned over to the first-contact and military branches of government.
The first-in scout can be a robot probe, but this poises a risk. In alien star systems, there is a huge chance of the probe encountering a situation totally outside the bounds of its knowledge set and initiative. In Larry Niven's "Known Space" series, there are quite a few colonies founded on really nasty planets because the scouting ram-robot space probes were programmed by people with insufficient imagination.
Scouting a new planet is a notoriously dangerous job. The scouts will have to discover the hard way what a new planet has to offer in the way of deadly plagues, hideous carnivorous animals, poisonous plants, geological death-traps, and killer weather. Not to mention alien inhabitants.
Scoutships will be equipped with huge remote sensing sensor suites to scan the entire planet in detail from orbit.
Scoutships need extensive sickbays or auto docs, to try and sew the scout back together after some planetary hazard has mutilated them. It would make sense to initially send out robots so the various planetary death-traps are discovered by something expendable.
The scoutship hulls should be armored like fortress walls in case something or somethings try to claw or shoot their way in.
And of course a self-destruct mechanism in case they run into something civilization-threatening that the scouts can't handle.
Scouting becomes really tricky if they stumble over intelligent aliens. If the aliens have starships, it is vitally important that they do not discover the location of any human planets. But chances are any aliens discovered will be either apes or angels. If it is the former the scout can play god over the primitive cave-man aliens. If it is the latter the scout will be placed in an alien petri dish and studied in an alien lab. It is highly unlikely that the alien's technological development will be equal with the humans, no matter what you saw in Star Trek.
In any event scouts will have some sort of training for "first-contact" situations.
The traditional way that scouts look for intelligent aliens is to check the radio waves for alien transmissions, and to check the neutrino detectors for evidence of alien fission or fusion power plants. This allows the scout to spot aliens at a range far enough to beat a hasty retreat. Usually.
And if the scouts detect gamma rays with a precise energy of 511 keV, it means they've discovered an alien civilization powered by antimatter, and should immediately run for their lives as stealthfully as possible.
Scouts may find Forerunners ruins or artifacts, remains of a long extinct alien interstellar empire. There also might be Forerunner xenopaleotechnology, high-tech artifacts of a higher tech level than yours. Such artifacts are both incredibly valuable and incredibly dangerous.
They are dangerous because messing around with alien technology you do not understand can kill you hideously. They are also dangerous because pirates and rogue interstellar Indiana Jones types love valuable things, so they are motivated to kill you on the general principle of Dead Men Tell No Tales.
There is the slight risk that the Forerunner race is not long dead but actually only mostly dead. If a Forerunner survivor becomes angry at you desecrating their tombs they will obliterate you with their higher-tech weapons. Even if they are long dead; their installations' automatic defenses, guard robots, and booby traps might still work.
Sometimes surveys will come in waves, with grand names like "The Third Uranographic Survey". Otherwise the surveying will be a constant low-level effort. In some science fiction novels (notably Andre Norton's "The Sargasso of Space") the Scout service will hold auctions for the right to establish colonies or to have monopolies of any trade goods on newly discovered planets. The former type is of interest to potential colonists, the latter is of interest to interstellar traders (both megacorporations and independent free traders).