Gigantic Space Station

Owner: Earth Union
Location: Earth Orbit
Add-Ons:
- Unknown
Mobile Suits (???):
- Unknown
Mobile Armors (???):
- Unknown
Defenses:
- Unknown
Occupants:

Sentinel is the Earth Union’s relative “border checkpoint” for Earth, and its only notable installation in space of any type. It is placed in a non-synchronous, relatively low orbit (~390 km), completing one revolution of Earth about every ninety minutes. The station is based off of an incredibly heavily modified Stanford torus-type space colony, whose incomplete frame was “borrowed” by a joint Alliance/League task force in UC 220 from the L4 shoal zone and moved to geostationary orbit while construction work was resumed. The installation was completed in June of UC 224, now under the Earth Union’s banner, with only a fairly vague resemblance to its original form.

The torus-shaped colony structure itself has been augmented by four massive “arms” that project out from its equatorial axis, each bristling with a dizzying array of GN beam cannons and missile launchers. The arms rotate independently of the central structure, and can be halted entirely without altering the fortress’ rotation (typically during combat alert periods). As a military fortress, both the arms and the “wheel” have been heavily reinforced and plated with GN particle-impregnated materials, making it significantly more durable than typical space colonies or PLANTs. Instead of open air and natural turf, Sentinel’s wheel is essentially filled with tower blocks and monolithic structures, resembling a city in only the most liberal of senses – the interior could be more easily compared to ship than a space colony, with environment synthesized from harvested materials while carbon scrubbers purify the spent atmosphere.

In order to prevent rogue elements from harassing the fortress’ duties with regulating traffic to and from Earth, Sentinel is a veritable bastion against attack of all sizes. GN missile launchers and beam cannons, the same type employed on the Union’s GN Battleships, dot both sides of the station’s arms, with a single monstrous GN mega cannon positioned in the tip to provide maximum firepower against very distant targets, such as ships attempting to run the checkpoint. An innumerable amount of anti-beam gas mortars line the fortress’ outer shell, providing it a strong defense against potent beam weapon attacks. Finally, and perhaps most nefariously, is the very original minefield that “lives” around the station. The roughly spherical cloud of self-propelled GN bombs are intricately held in place by the space station’s gravitational pull, effectively matching its rotation, with a small number of safe “channels” to allow ships and mobile suits to approach the dock facilities. The mines employ a rather sophisticated IFF sequence to remain inert and dormant while Union ships and mobile suits pass by, otherwise the mines activate on detection of movement or GN particle emissions not originating from an authorized source.

To maintain its role as Earth’s checkpoint to space, the station utilizes a large series of communications and observation satellites rigged to match its orbital velocity albeit significantly higher, effectively allowing Sentinel to “peek around” the planet’s curvature. These automated “eyes and ears” transmit their feeds via encrypted laser communication to Sentinel’s powerful computer cores, processing the incoming information into a comprehensive visual reference of traffic to and from Earth’s surface. It is beyond the capability of even the best technology to pinpoint mobile suit-sized objects amid the debris drifting through Earth’s orbit from geostationary altitude, but more obvious feedback – surface launches and re-entries – come back as pronounced reports that are easily detected and plotted. Breaks in the system (e.g. a satellite being destroyed) provides immediate feedback to Sentinel, and the individual platforms are designed to self-destruct if tampered with.

While not nominally a mobile installation, Sentinel is provided with a powerful array of GN verniers, allowing it to alter its altitude and relative bearing as necessary. The station is theoretically capable of “parking” for a protracted period of time as well as leaving Earth orbit entirely, although it never has.