The Hansens' mission
Prior to the USS Enterprise-D's first encounter with the Borg, the Federation had little knowledge of their existence, based on encounters with surviving members of species that had been destroyed by them (such as the El-Aurians). However, empirical data on the Borg was very scarce. For example, there were descriptions of cube-shaped vessels, but no information on what Borg individuals looked like, other than rumors that they were cybernetically enhanced. Therefore, in 2353, Magnus and Erin Hansen petitioned the Federation Council on Exobiology to support them on an independent research mission to study the Borg. The Council agreed, providing them with a vessel, the USS Raven, despite security concerns expressed by Starfleet.
They made their preparations and, on stardate 32611, with Annika in tow, they set off. They made a stop at the Drexler outpost in the Omega sector, as recorded in the logs of the space station Deep Space 4. After leaving the station, however, they deviated from their flight plan, disobeyed direct orders to return and crossed into the Romulan Neutral Zone, effectively leaving the protection of Federation space. (VOY: "The Gift")
After tracking stray readings and sensor echoes for eight months, the Hansens were able to locate a Borg cube. The Raven trailed the cube, following it into a transwarp conduit all the way to the region of the Borg's origin, the Delta Quadrant. (VOY: "Dark Frontier")
The Hansens designed new technologies to allow themselves to study the Borg more closely and prevent the Borg from detecting them. They developed multi-adaptive shielding that made the Raven virtually invisible to Borg sensors, and bio-dampeners to mask their bio-signs while on Borg vessels. Magnus visited Borg cubes in person to observe first-hand the behavior and interactions of Borg drones. He and Erin also transported regenerating drones onto the Raven for study. The Hansens became very well-versed and comfortable in their endeavor, even giving certain drones nicknames such as "Junior" and "Needle Fingers." They continued researching the Borg for over three years, collecting ten million teraquads of data. (VOY: "Dark Frontier")
Then, in 2356 on stardate 32634.9, the mission came to a disastrous end. A subspace particle storm damaged the Raven's multi-adaptive shielding, putting it offline for 13.2 seconds. The Borg detected the Raven and deemed it a threat. Pursuit of the Raven began and attempts to escape them by masking the ship's warp trail failed. The Borg caught the ship and assimilated the Hansens and their daughter, who later became known as Seven of Nine. Erin's current whereabouts and status are unknown, though it is assumed that she (if still alive) has remained a Borg drone since the family's capture.
The Raven itself was partially assimilated, but the Borg chose not to keep it, and it eventually crash landed on an M-class moon orbiting the fifth planet of a yellow dwarf star in the region controlled by the species known as the B'omar.
For the first portrayal of this character, Nikki Tyler filmed her scenes on second unit on Thursday 17 July 1997 on location at the grassy area in front of the Paramount Administration Building on the Paramount Pictures lot. She is listed as "Mother" on the call sheet and had a makeup call at 7:15 am and a set call at 8:45 am. She filmed her scenes under second unit director Michael DeMeritt with fellow actors David Anthony Marshall and Erica Bryan and their stand-ins Keith Rayve, Cameron, and June Jordan.
Tyler is also listed as "Mother" on the call sheet and in the end credits of her second appearance, the episode "The Raven". For this episode she filmed her scene on Monday 28 July 1997 on Paramount Stage 16.
Erin Hansen's appearance in "Scorpion, Part II" was not scripted, with the shooting script of "The Raven" being the first teleplay to feature the character. The script of "Dark Frontier" describes Erin Hansen much more significantly than "The Raven"'s script, however, introducing her by stating, "She looks early to mid-thirties, has a dry sense of humor and an astronomical I.Q."
The Pocket TOS novel No Time Like the Past gives her mother's name as Elaine Bergstrom, a security officer aboard the USS Enterprise in the 2270s, whose death Seven helps to prevent by destroying a time/space travel device before it can be used or hunted for by the Orions.