Well, i dont think itl do much damage during veg, specially if you only do it once. Its definitly not good for it however, avoid this.
i thought about this interuption for awhile, so i did some tests, yes it does hurt the plant if the light is first a high lumen output and if it is exposed than more than a certain amount of time, otherwise its fine for the small amount of exposure but make sure not to do it patternistic as it will be sensed by the plant and cause disruptions
Mine grow outside on my roof. There is a bright sodium streetlamp within 50 feet - has no adverese effect whatever. After all, MJ has evolved under a bright moon.