In Avengers # 676, the second chapter of the story "No Surrender" where the Earth has mysteriously been "stolen", sending the world into chaos and calling all active and retired Avengers to action, we learned a lot about a mysterious character named Voyager.
Voyager was presented for the first time in Marvel Legacy # 1, when it was shown to be part of the statue of the founders of the group of superheroes that is outside the Mansion of the Avengers.
In this issue, it was revealed that in fact she was a founding member of the team and participated in many iconic moments over the years.
As for why it disappeared, it is reported that in Avengers # 70, the protagonist was forced to fight another "forgotten" character called Victory, The Electromagnetic Man as part of a game between the villains Grandmaster and Kang.
When the powers of both interacted, it caused them to inexplicably disappear from existence and memory.
This until at the events of Avengers # 675, where the Earth moved in some way that got her back to reality and immediately received the call of the Avengers. Some of the current members of the group remember her, others do not and we will surely know more of what happened to her while "No Surrender" continues. With Voyager back, it is almost likely that the same will happen with Victory.
The real question is whether Marvel will really re-connect the story of the Avengers and the Marvel Universe to include the heroine - not like they did to present Sentry - or if some character is manipulating reality and perception in order to use Voyager to achieve a hidden mission. Let me know your opinions in the comments.