The file extension suggests that this is the second part of a compressed archive (Gzip). In 2009, large video files were often split into multiple parts to make them easier to upload or download on older internet connections; you would typically need all parts (part1, part2, etc.) to successfully extract and watch the full video.
This indicates the file is the second part of a split archive and has been compressed using gzip (.gz) to reduce its size. The file extension suggests that this is the