The Orex II Gravity Well is an area of space located inside the Orex star system affected by the gravitational field of its second planet.
Nebula and Gamora engaged each other in fierce combat in a competition to retrieve a data ingot for Ronan. The girls were evenly matched and their fight led them to a cliff, where Gamora tossed Nebula over. Nebula was severely injured in the fall, and is forced to undergo cybernetic augmentations. Later, as she was repaired, Thanos openly expresses his disappointment on her, lecturing her on the limits of weakness.