Short answers, pulled from the story.
Veneneia crater is 395 kilometers in diameter, making it the second-largest impact crater on the asteroid Vesta. That size equals roughly 70% of Vesta's own equatorial diameter, placing it among the largest craters in the Solar System.
Veneneia is at least 2 billion years old. Scientists estimate it could be as old as 4.2 billion years, which would place its formation in the early Solar System.
Veneneia was discovered by the Dawn spacecraft in 2011. Dawn's observations revealed the crater's size and its connection to large-scale fractures on the opposite side of Vesta.
Veneneia is overlain and partially obliterated by Rheasilvia, an even larger impact basin that formed after Veneneia. Rheasilvia has erased a significant portion of Veneneia's rim and floor.
Saturnalia Fossae is a system of troughs on Vesta's northern hemisphere that are concentric to Veneneia. Researchers believe these troughs, with the largest stretching more than 400 kilometers long and around 39 kilometers wide, are large-scale fractures caused by the Veneneia impact.
Veneneia crater is named after Venenia, one of the founding Vestal Virgins of ancient Rome. The Vestal Virgins were priestesses dedicated to the goddess Vesta, who is also the namesake of the asteroid on which the crater sits.