Why isn't Mosche Niederland's Yahrzeit Exact?

We do not know the exact date of death of Mosche Niederland. According to Jewish tradition, if the exact date of death is not known, the yahrzeit of a person can be observed on any day, as long as it is that same day every year. Since that is the case, we observe the yahrzeit of Mosche Niederland on 18 Kislev. If you know the exact date of death of Mosche Niederland, contact us via the contact page. Be sure to include the url: https://eachofushasaname.org/person/4391/Mosche_Niederland.html