PLANETARY DEFENSES
or
How to defend the Earth from space attacks
This is a lengthy post.
Many planets in both Star Trek, Star Wars and Buck Rogers in the 25th Century and even more that I cannot remember their names have sported not only surface based and orbital weapons, fighter defenses. Nevertheless the above three have sported the powerful planetary shields. This is here will lay out what I call the onion defense system. It is laid out just like an onion with multiple layers of defenses including all the above. This was used in a Star Trek episode we ran where the Borg was attacking a well defended planet with all of the following defenses that I will explain in detail. Some of what I propose is bending some of the rules… no twisting them like a pretzel to make this defense work… nonetheless it works.
(As a note the Resurrected version of Battlestar Galactica series made mention in one of the first season episodes of a planetary defense network which I believe were anti-aircraft guns and surface to air missile launchers with no shielding systems as it was beyond their technology.)
First let’s start with the planet I will be using the friendly old Earth as an example. The Earth is 12,756 kilometers (taken from The Writer’s Guide to Creating Science Fiction Universe) in diameter with a circumference of 39,249 kilometers (estimated using FASA system) with a surface area of 500,501,284 square kilometers (estimated using FASA system). At roughly 160 kilometers the atmosphere ends and space begins’ there. The air but far too thin to bother with worrying about. This is the ionosphere going out to 1000 kilometers where the atmosphere is finally blown away by solar winds.
Let’s get started where with the defense before I start in on the offensive weapons of defense.
PLANETARY DEFENSE
There are three shielding to this defensive system. Here is where the onion comes in there are three layers the orbital shield, the city shield and individual building shields.
Important buildings can have shields such as weapons facilities, power production, command centers, facilities, medical, defense shelters and communications, the list can be endless. These facilities are not listed in any order of importance. These are like an umbrella stopping just above street level protecting the building and those out side of the building.
City shields are the next layer out they cove the city just like the individual building shields do at least a kilometer or two above. Their interlinking shielding multiplies their defense levels so as an example a small circular city three kilometers could have five shielding projectors and thus the interlaced fields would strengthen the shield so a single shield integrating with five others would increase the protection five times that of a single shield if they are all set to the same shielding calibrations. These shields umbrella overlap one another strengthens and supporting the other this is how it have come up with the shield enhancements following is an example. So, a lone shield 1000 protection and a threshold of 300 would now integrate would have 5000 protection and a threshold of 1500. This means that it would take at least three Galaxy-class ships firing together three shots a peice to make a dent in the shields.
Orbital shields are in orbit 200 to 250 kilometers above the surface located in the ionosphere where the air is thin. So, the shield is 13,165 kilometers wide at 200 kilometers high and has a surface of 516,549,029 square kilometers. If your orbital satellites can cover ten square kilometers each overlapping one kilometer you would have over 64,000,000 satellites. I would use a shield generator for a spacedock size 50 ship scale creating a seventy square kilometer shield umbrella overlapping twenty kilometers ten per side thus you would only need just over 10,000,000 satellites. Nevertheless, each satellite with a shield protection of 1400 protection and 450 threshold would have six overlapping satellites increasing the protection seven times that of a lone satellite. So, your orbital shield would be generating a 9800 protection with a threshold of 2940 requiring five Galaxy class starships firing three shots each to begin to make a dent in the shield. Shields on maximum your protection would be 14,700 requiring an all-out assault from eighteen Galaxy-class starships firing FIVE shots each to overwhelm the shields completely breaking down the protection.
The tactical advantage of the overlapping shields is that it raises the shielding but if one satellite is destroyed there is a hole, so I would suggest that the satellite’s shield umbrella cover to next satellite if possible. Then if one satellite is destroyed the neighboring satellites adjust their position slightly and then the hole is covered shortly. In that time a ship can slip through the opening. You would need over 14 million satellites.
If your planet has planetary shield umbrella projectors it works, the same but when the facility fails or is destroyed the other facilities can not adjust their position to compensate like satellites. You could use both orbital and ground bases as well.
I will post an example of the shield satellites and ground-based shield projectors later.
PLANETARY OFFENSIVE SYSTEMS
It was said once by someone that the best defense if a good offense. I agree but then again there are some who don’t want a weapons system sitting in their backyard. I can see their point of view as it would paint a bullseye on you. but let’s put ground base energy weapons arrays one per small cities, three for a medium city and five to seven per large city or scatter them about one per every 5000 square kilometers of solid surface. With each energy weapons array having 540 degrees of firing arc any ship attempting to attack the surface of the Earth would have to be in the sight of one of these weapons unless they were attacking the water. Attacking over the water would limit the number of energy weapons s that could hit you but if you were knocking a hole in the shield to allow smaller ships in then it makes sense. That would be twenty-nine thousand planetary based weapons arrays littering the planets surface and with three to six persons manning each that would require two-hundred thousand plus persons unless the arrays were automated somehow.
In conjunction with the planetary defense and offensive systems there would be orbital satellites that would be either automated or maned capable of firing not only energy weapons but missiles as well. These orbital satellites stations could be integrated into the shield satellite system defending the neighboring satellites and taking potshots at the attackers. Each of these stations would take care of the repair and maintenance of the shield satellites when they are not protecting the planet. One Command and control satellites space station per every 250 shield satellites. I would suspect that most would litter this out to five hundred kilometers from the surface and naturally they would all have overlapping fields of fire covering the neighboring satellites from attack.
Then there is the idea that I am not a fan of mines. Not only are they a navigational hazard they can drift out of their position. In space they are kept in place by thrusters as the on Earth they are anchored to oceans floor. The whole idea of a mine is as a blockade that only you have the way through and as a deterrent to whom ever comes across them keeping them out. Don’t get me wrong I understand they are a tool of warfare I just don’t have to like them. Just this summer there was the discover of a mine drifted into the Seattle sound area that they had to toe out and dispose of. I see them as more trouble than they are worth. I can see that if you know the enemy is coming you litter the area with mines as a defense then that makes sense in preparation for their arrival but after you place them, and they are not used you have to go get them. Each mine is size one with an explosive yield of at least 100 damage depending on their type.
Starship and fighter defense this can be any armed ship whether a shuttle or starship that stands a defensive perimeter one hundred kilometers out from the planet confronting the approaching the planet. One ship against an armada good luck, ten ships a little better depending on what kind of ships they are. In the Star Trek: The Next Generation episode Best of the Both Worlds mars had hot dog shaped fighters that attempted to assault the Borg Cube and were quickly swatted away with superior numbers these little ships could maybe have made a dent… no I guess not. I have never worked up these little ships as I don’t have much to go one other that the thought that they are all guns, shields and engines and little else with maybe a warhead for after ramming into another ship.
So here is how it all works.
The armada approaches the planet. Once Armada have ignored the warnings to approach the first layer of the Onion, the orbital defense satellites open fire taking out who and whatever they can. Naturally the armada has to clean out these satellites. Littered in among these will be the mines whether the Armada sees them they have to be cleaned out. This should take a toll on the Armada causing them to lose a few ships.
Once the outer layer is taken care of the second layer of the onion is the defense ships and what ever ships that have arrived sense the long-range sensors have detected a very large group of ships approaching. This does not preclude the defensive fleet from taking pot shots at the Armada during their tangle with the satellites. Among these will be the defensive space stations, starships, armed shuttlecraft, and fighters or what ever they have available. This does not preclude a few fast ships hiding behind the moon or dust ring swinging around in a pincer move and attacking the side or the back of the Armada.
Now if that onion layer is peeled away the shield is the line of defense. The Armada would likely be down to half its fleet if the defenders are good and lucky. The Armada would start probing the shield with a shot here and there testing it for a weakness. While this is happening the surface batteries would be blasting away as well as the defenses that are closer to the shield. This would eliminate a few more ships here and there.
Hopefully the defender’s reinforcement arrive in time and drive the Armada off. The defender’s reinforcements have fresh supplies and well rested, while the Armada has expended a good deal of energy and supplies to get this far, and the crew would be battle weary. This all depends on how many ships are left and how many reinforcements there are.
If the Planetary Orbital Shield fails, the Armada has to either land ground assault forces that are either on the ships that have survived or standing off just out of the system or begin an assault on the city shields. The objective it to take the cities without loosing them too much to damage. This is where the ground forces have to land and fight the forces on the surface. The Borg would attack the shields and anyone else would likely land ground forces.
If the Armada succeeded the planet is there at a cost.