1998

• When SG-1 explored the planet Cartago (P3X-1279) and made first contact with the Byrsa people, Teal'c was recognized as once having been the First Prime of Apophis, and was put on trial for killing Hanno's father. Hanno realeased Teal'c however, when the planet was attacked by Apophis and he saved the Byrsa people.

• On an exploratory mission to the planet Tollan (P3X-7763), SG-1 found several survivors of an advanced civilization called the Tollan and returned them to their civilization.

• The Stargate malfunctioned whilst SG-1 were evacuating from a firefight on P4A-771, which sent O’ Neil and Carter to a previously unknown second Stargate in the ice of Antarctica. O'Neil and Carter were rescued, and the Antarctica Stargate was stored at Area 51.

• On arrival to the planet designated PX3-989, SG-1 were rendered unconscious and their consciousness were copied into the bodies of duplicate androids. SG1 were eventually returned to Earth, and their duplicates remained on PX3-989 with Harlan.

• On P3R-233, Daniel discovered the Quantum Mirror which transported him to an alternative version of Earth. An Earth were he never joined the SGC and which was under attack from the Goa'uld. Altenative members of SG-1 sacraficed their lives, so Daniel had enough time to return his own reality with a note containing the Stargate address of the world that was the staging point for the invasion.

• Daniel Jackson warned the SGC that an attack in Earth is imminent. Robert Kinsey however, recommended shutting down the Stargate program. SG-1 made an unauthorized mission to prevent Apophis' attempt to invade Earth. SG-1 succeeded, causing Apophis' position among the System Lords to weaken and allowed the Stargate Program to remain active.

(SG1: "Politics")
[(SG1: "Within the Serpent's Grasp") (SG1: "The Serpent's Lair")

• While SG-1 helped a group of people on the planet Nasya flee through the Stargate from a Goa'uld attack on their world, Captain Carter unwillingly becomes the host of Jolinar of Malshur, a Tok'ra symbiote.

• SG-1 are sentenced to life imprisonment in Hadante, an underground prison accessible only through a Stargate, which has no Dial Home Device (DHD). A prisoner called Linea however, helped SG-1 to escape through Stargate, which also ensured her own freedom. But when SG-1 returned to Earth, the SGC realized that Linnea was actually the notorious criminal nicknamed the "Destroyer of Worlds", who created a disease that wiped out an entire planet. Linnea escaped through the Stargate, before the SGC could re-capture her.

• SG-1 team travel to P7J-989 and were trapped inside a virtual reality machine. SG-1 are forced to relive past events, which included watching their friend and family die, as entertainment. SG-1 managed to escape, and in the process also helped the other inhabitants leave the virtual reality machine.

• While exploring P3R-636, Daniel saved a young women called Shyla, the daughter of Pyrus The Goslayer, leading SG-1 to become enslaved and forced to work in the Naqahdah mines. Daniel also become addicted to a sarcophagus.

• On Cimmeria, the System Lord Heru'ur attempted to subjugate the Cimmerians protected by the Asgard. SG-1 however, were able to contact the Asgard called Thor, who came in his vessel (Thor's Chariot) and removed the Goa'uld on Cimmeria.

• While SG-1 explored the dead planet P5C-353, they discovered an orb that sent out electromagnetic signals. Believing the orb contained messages from a lost civilization, SG-1 brought it back to Earth. However the Orb contained organisms which infected everything it touched, metabolizing its subatomic structure. SG-1 agreed with the organism to send the orb through the Stargate to P4G-881, which was a primordial world with no civilization.

• Teal'c's son, Rya'c, was kidnapped and brainwashed by Apophis. SG-1 and Bra'tac traveled to Chulak and rescued Rya'c, who was then un-brainwashed by Teal'c.

• Daniel returned to Abydos to inform his father-in-law Kasuf that he was been unable to rescue Sha're, but he discovered that Sha're was already on Abydos, and was carrying Apophis' child. Heru'ur, sworn enemy of Apophis, intended on stealing the child when he landed his mothership on Abydos, but Daniel and Teal'c gave the baby to Kasuf, who went into hiding.

• On an exploratory mission to BP6-3Q1 Teal'c is stung by a giant insect. When Teal'c returned to Earth, the venom began to rewrite his DNA, which nearly caused Teal'c to transform into the insects offspring.

• SG-1 make first contact with the Tok'ra on the plant P34-353J and Jacob Carter willingly becomes the host to the Tok’ra symbiote Selmak.

• When SG-11 do not return from PXY-887, SG-1 leads the SG-1 team through the Stargate to find SG-1 and negotiate with the mystical natives for a precious mineral called Trinium.

• A group that posed as the team SG-1 stole the climate-controlling Touchstone from the planet Madrona (PX7-941), which caused the plant’s weather to deteriorate, threatening the inhabitants with imminent death. The SG-1 made the disturbing discovery that the second Stargate on Earth, which had been officially decommissioned, had been reactivated by high-levels and used to steal the touchstone. SG-1 regained the touchstone and returned it Madrona, but the team who posed as SG-1 escaped through the second Stargate.

• While attempting to save the members of SG-10 from a black hole on planet P3W-451, the SGC activated the Stargate and created an artificial Wormhole between the two worlds, exposes themselves to the black hole's gravitational pull. Even without power, the black hole's gravitation continued to draw the SGC closer, warping the space-time continuum. Colonel Cromwell and O'Neill, placed an explosive device near to the event horizon, which caused the wormhole conneted to the Earth's Stargate to disengage.

• SG-1 travelled to the plant P3R-272 and encountered a device called the Repository of Knowledge, which downloaded the Ancients knowledge into O’Neill’s brain. The Ancients knowledge allowed O’Neill to add new Stargate destinations in the SGC computer, previously not from the Abydos cartouche. O’Neill also created a power-source that enabled the Stargate to dial an 8 chevron address. This enabled O’Neill to travel outside the Milky Way Galaxy and make physical first contact with Asgard race, in the Ida galaxy.

• Sometime in that year, the Wraith culled Sateda, which ended up in all but 300 Satedans killed or culled.