Stalker: Call of Pripyat → Quests → Surviving Monolith
Duty or Freedom:
- Give Morgan's PDA from the "Deal" quest to Duty or Freedom.
- Give one of them the Chief Debt Officer's PDA, obtained in the " History of Debt " quest.
- Complete the "Magpie" and "Retribution" quests for Duty or Freedom.
- If that's not enough: Agree on protecting the scientists in favor of Duty or Freedom.
The former Monolithists are located in the northwest area of Jupiter, though they're not on Yanov. Waiting out the emissions in the open isn't the most pleasant thing a stalker can expect, so let's help them out. They can be assigned to Freedom or Duty by talking to the commanders of these factions, but you'll need to earn their respect.
Editor's note: It's advisable to decide from the start which faction you'll be supporting so you have enough reputation to complete the quest. Give everything to either Duty or Freedom. Or no one at all. :)
See also:
Solar Eclipse. Events of Terraria