 Astronomical objections centered on the fact that dust reddening and cloud silhouettes were used to determine that the outer arms lead.The galaxy disk is tilted only 19 degrees from face-on making near to far-side effects of dust hard to discern and because clumpy dust clouds might be concentrated on one side of the disk, creating misleading results.In response, the “backward astronomers” determined NGC 4622's spiral arm sense with a method independent of the previous work.