Scenario: Alien Invasion 2012

We were warned by the Mayans. But we didn't listen. We paid the price on December 21st, 2012.

2012

 * Throughout the year, UFO sightings reach a new high. The US Government is forced to reveal the true purpose of Area 51.
 * Messages from space start coming in. A well thought-out speech announces an invasion on December 21st, 2012. Most of humanity believes that it's just a prank. But government officials worry that humanity is at great risk.

Doomsday
All times Pacific Standard Time.
 * 12:01 AM: A message from the aliens comes through, saying that by day's end, they will be killed. US President Barack Obama declares DEFCON 2.
 * 12:05 AM: Contact is lost with the International Space Station.
 * 12:18 AM: The first alien saucer comes into Earth orbit. Obama orders that space junk be diverted into the ship.
 * 12:20 AM: The space junk causes the saucer to crash into the Sun.
 * 12:56 AM: The alien Invasion Fleet approaches Earth orbit.
 * 1:00 AM: Reports of small skirmishes between Syrian rebels & aliens start pouring in.
 * 1:05 AM: The Moon is taken over by the aliens.
 * 7:00 AM: News of the fall of Libya reaches the White House. Obama declares DEFCON 1 & orders all nuclear forces into launch-ready position.
 * 8:00 AM: Aliens start all-out assault all over the world.
 * 8:12 AM: Alien saucers begin relentlessly pounding population centers.
 * 8:13 AM: A resistance group in San Jose, CA, successfully manage to defend the city and place a stolen shield generator at the center of the Silicon Valley. No aliens enter the Silicon Valley for the rest of the invasion, and it becomes a safe haven for survivors and resistance groups.
 * 8:16 AM: Barack Obama is killed.
 * 8:17 AM: David Cameron is killed.
 * 8:23 AM: London falls.
 * 8:24 AM: San Francisco and New York fall.
 * 9:05 AM: All of the world's nuclear weapons are launched at the alien Fleet. At least 5 Saucers and 500,000 aliens are killed.
 * 9:32 AM: Fighting between alien and military forces intensifies. Special Weapons aliens begin assaulting fortified positions.
 * 10:53 AM: Chicago falls.
 * 12:18 PM: Sydney and Moscow fall.
 * 1:12 PM: Los Angeles falls.
 * 2:45 PM: Resistance groups have been mostly destroyed by this time.
 * 3:05 PM: The aliens' High Command decides to begin building processing plants where human prisoners will be systematically exterminated.
 * 3:30 PM: 60% of humanity is dead.
 * 4:51 PM: 65% of humanity is dead.
 * 5:13 PM: The alien leader orders a series of earthquakes to be set off along the major faultlines to snuff out survivors.
 * 6:00 PM: The alien leader declares the fighting to be over.
 * 7:27 PM: 80% of humanity is dead.
 * 8:00 PM: The earthquakes are set off, snuffing out 70% of the survivors.
 * 9:05 PM: Alien patrols find over 1,000,000 survivors.
 * 10:54 PM: The alien leader declares Earth the new homeworld of the alians.
 * 11:59 PM: At the end of the day, an impressive 10,000,000 humans survive.

Epilogue
After the invasion, the aliens killed most of the survivors. Three years later, a resistance group comprising of four teens (two American, one British, and one Japanese) overthrew the alien puppet government and killed the alien leader..