First Battle of Earth

Summary
DATE: October 20, 2552

LOCATION: Sol System, above planet Earth.

Involved: UNSC, Covenant forces.

Synopsis: This battle was somewhat unexpected. Fortunately the UNSC was more than prepared to defeat the Covenant. The more important task now is defending the planet during The Second Battle of Earth.

Outcome: UNSC successfully repels the invading Covenant but most of New Mombasa is destroyed.

UNSC
Commander: Fleet Admiral Sir Terrence Hood

300 Orbital Super MAC Cannon Platforms.

8 Cruisers (possibly ALL Marathon Class)

67 Frigates

1 SPARTAN-II supersoldier: SPARTAN-117

1 Confirmed Spartan-I soldier: Sergeant Avery Johnson

The Covenant
Commander: The High Prophet of Regret

2 Assault Carriers

13 CCS-class Battle Cruisers

Timeline
No official timeline is given, however the events of Halo 2 sum up the basic attack. Lord Hood, SPARTAN-117, Sergeant Johnson and Miranda Keyes are in an awards ceremony on the Cairo Station when the Covenant task force exits slipspace just beyond the range of the MAC satellites. Fleet Admiral Harper, in charge of the Earth defense fleet, prepares to engage the Covenant, however he is overriden. The Covenant launch boarding craft at the vessels and stations. Several vessels and stations are destroyed by boarding Covenant forces. When they feel they have made enough damage, the Covenant punch a hole through the Human defense and land at New Mombasa, Kenya. SPARTAN-117 pursues the Covenant forces, who have dropped a Scarab on the ground. After it is destroyed, the Prophet of Regret and his Assault Carrier enter Slipspace inside the city. New Mombassa is destroyed, but the UNSC In Amber Clad follows the carrier through Slipspace, ariving at Installation 05. The remaining Covenant vessels around Earth either disperse or are destroyed.

0140 hours- Slipspace whisper heard by Io. Minutes later the covenant fleet arrives with about 15 capital ships. Between 0140 and 0150 hours-Fleet Admiral Harper assembles the fleet. Covenant start sending small boarding craft to Cairo, Athens, Malta MAC gun stations to destroy them. Malta, unaware of the bomb on the station, happily reports Covenant boarding parties fleeing. A few seconds later and Malta is destroyed by the bomb. A few minutes later the Athens is also destroyed. Cairo is granted permission to open fire on the Covenant fleet. Then, Lord Hood sends the Master Chief to disarm the bomb.

Between 0150 and 01630 hours- Covenant start deploying forces in the area, including a Scarab for heavy armor. Sergeant Johnson and Master Chief's Pelican is shot down by the Scarab and hunker down at an isolated position and wait for extraction. Gunnery Sergeant Pete Stacker and a ODST squad move up the beach to Hotel Zanzibar and set up a bunker, wiping out several Covenant units along the way. Sergent Johnson is extracted to help with armored units entering the city. Pinned down units in Hotel Zanzibar are saved by Spartan 117. Units at the bridge are decimated as the Scarab blows through any and all UNSC forces. Spartan 117 arrives at bridge to assess situation and reinforcments are sent including a Scorpion Battle tank. The 405th out of Diego Garcia make landfall at city square and are quickly surrounded by Covenant troops. 105th ODST unit lead by Spartan 117 are called to city square for a last defense. Scarab is taken down as Prophet of Regret flees.

Forerunner Links
The following is pure speculation.

Cortana states during gameplay that the Covenant didn't expect any human presence on Earth. It is widely speculated that the Prophet of Regret simply considered Earth another Human colony, and not the Earth homeworld. However, another possibility exists. Considering that Coral contained an artifact of almost certain Forerunner origin, and that the Covenant definitely encountered this artifact; that, after their encounters with Forerunner technology on Installation 04 they are likely much more capable of understanding Forerunner information; and that Cortana was able to deduce the location of Installation 04 from a Forerunner artifact without extensive contact with Forerunner technology; it is likely that Covenant species, armed with their new ability to decode the not overly complex language of the Forerunner, deciphered the information stored in Coral's artifact to reveal the location of the Ark. The Prophet of Regret then rushed in to secure the Ark, without realizing that it was in fact the Human homeworld.

UNSC

 * Malta Station
 * Cairo Station
 * Athens Station
 * UNSC In Amber Clad

Covenant

 * Pious Inquisitor

UNSC

 * SPARTAN-117
 * Sergeant Major Johnson
 * Fleet Admiral Sir Terrance Hood
 * Commander Miranda Keyes
 * Major Easley
 * Fleet Admiral Harper
 * Private McKenzie
 * Corporal Perez
 * Sergeant Banks
 * Gunnery Sergeant Pete Stacker

Covenant

 * High Prophet of Regret