Look, Rahu period is that time which is considered suitable for prayers. It is considered ideal for any spiritual activity. So beginning any wordly project during that period is not considered appropriate because in our body there is a switching of channels (naadis) at that time.
However, we should not attach too much importance to this. If you absolutely have to do your work at that time, just say, ‘Om Namah Shivaya’ and move forward.
