Bring Down the Sky

Bring Down the Sky was the first downloadable content released for Mass Effect, and was announced to be bundled for free with the PC version, which was later changed to "downloadable for free". The mission takes place in the Asgard system, where an asteroid has been hijacked and sent on a collision course with the human colony of Terra Nova.

Plot
"Terra Nova will die, Shepard. Not just the colony. The planet." - Simon Atwell

Kate's Message
On approaching Asteroid X57, the Normandy's computer reports that the asteroid, propelled with huge fusion torches to become a new orbital facility, is heading toward Terra Nova too fast. As the Mako drops on the surface to investigate, Commander Shepard receives an urgent message from a woman who sounds like she's in hiding. She says that 'they' are responsible for attacking the asteroid and begs whoever is receiving this message to shut down the fusion torches. Shepard enters the first torch station and discovers several troopers inside - batarian soldiers accompanied by varren. After clearing the station, Shepard finds the control station and shuts the torch off.

Another message comes over the comm from the mysterious woman. She says her name is Kate Bowman. She doesn't know why the batarians are here, but they've killed many of the personnel on the asteroid. Kate has to sign off before they find her.

Shepard leaves the station - and gets shot by a man hiding near the door. Luckily Shepard's shields take the shot and the man apologises, introducing himself as Simon Atwell, an engineer on X57. He tells Shepard that the asteroid is going to crash into Terra Nova and cause catastrophic damage. Not only will it destroy the colony and kill everyone on the surface, but the devastation will effectively kill the planet.

Shepard asks why the batarians are doing this. They're slavers, pirates, not planet killers. Simon doesn't know, but he has a warning. One of the fusion torches is surrounded by blasting caps. The Mako will set them off, so Shepard will have to approach on foot. Simon also asks the commander to look out for three members of his engineering team who haven't reported back. When Shepard asks if he knows Kate Bowman, Simon says she's one of his best engineers; both she and her brother Aaron signed up together. He hopes she won't do anything stupid.

Problems and Solutions
Shepard finds the next fusion torch, guarded by more batarians. Once the commander has disabled the torch there is another call from Kate, whispering that the batarians are really pissed off. Her message is cut short as her hideout is discovered - Shepard can only listen as the batarians find her. Kate's brother is held at gunpoint while Balak, the leader of the batarians, demands to know who's shutting off the fusion torches. Kate refuses to answer and turns away. Behind her back, Balak shoots her brother in the head. He then orders his second-in-command, Charn, to "find this problem and deal with it".

Elsewhere, having negotiated the blasting caps, Shepard leads the assault on the last fusion torch. Once it is shut down, Shepard is confronted by Charn, who suggests they try a peaceful resolution. He claims this was just meant to be a simple slave grab, but it's got out of hand. Balak is on a mission to destroy Terra Nova and the commander is in the way. Charn is under orders to kill Shepard... but he's getting tired of following Balak's little crusade. Shepard can use Charm or Intimidate, convincing him to get out while he has the chance, or just attack him. Either way, Charn yields a pass to the main facility.

Balak
Shepard enters the facility, which is guarded by turrets outside, and batarians and combat drones inside. Finally Shepard is confronted by Balak, who is furious that the torches have been shut down. He sees this as an act of reprisal for humanity's actions in the Skyllian Verge, stealing territories and resources that should have belonged to the batarians, all because the Council saw a military advantage in befriending the Alliance. Balak isn't going down without a fight. The remaining hostages are in one of the facility offices with a detonator, and Balak is holding the switch. Shepard then has to choose - let Balak go to save the hostages, or sacrifice them to take Balak out for good.

Either way, the entire facility becomes a battleground; either Balak's forces attack, or the building has been rigged with explosives overseen by hostile drones. Once Balak is gone and the area secured, Simon Atwell appears. Shepard can justify the decision to either save or sacrifice the hostages, and Atwell confirms that the commander's efforts worked. X57 was on a direct course for Terra Nova's capital. Now the torches have been disabled, X57 will miss the planet safely. Simon's family has been saved along with the entire colony. He offers supplies as a thank-you: Shepard can choose between human light, medium or heavy armor (the type depends on Shepard's current level), or a rare set of quarian armor. Shepard can also Charm or Intimidate Simon for a choice omni-tool.

If Shepard chose to save the hostages, the commander can then free them from one of the offices and finally meet Kate Bowman. She is glad to be alive but devastated at the death of her colleagues and her brother. Kate realises she never even asked the commander's name, and claims Shepard isn't what she expected, but she's very grateful for the help.

Tactics

 * You can receive Paragon points for using Charm or Intimidate on Charn. If you don't want to negotiate and attack him immediately, you get Renegade points. If you wait until the end of the conversation, then attack, you get neither.
 * If you allow the hostages to die and pursue Balak, the facility is not rigged with explosives to defuse.

Other Assignments

 * X57: Missing Engineers
 * X57: Avoid the Blasting Caps

Trivia
A small shack on a hill (near the fusion torch in the centre of the map) is home to X57 Radio, a small pirate radio station run by the X57 engineers. The computers mention a disagreement with the project director who wanted to shut the station down, because the music caused young engineers to "riot and sleep with aliens". When the director was asked if he'd actually heard the music, he said that he'd heard about it from someone else who'd heard something about what the station played. (PC only)

This is probably a response to the inaccurate reporting about Mass Effect's romance subplot that circulated after the initial Xbox360 release.

Achievement
Completing Bring Down the Sky gives the Colonial Savior achievement.