Q. We were learning on the Daf about the fact that you have to hold the lulav and esrog the upside way they normally grow. Since it is only a matter of time until we will be traveling in space, how do you hold the lulav on the moon?
A. Bikurey Yaakov (651 :13) debates whether Arva Minim that grew in another part of the planet are considered derech gedilosson (natural upright way of growth) in a different location or no. He and most contemporary Poskim maintain that if you hold them in your locality the way they would normally grow there, it is considered derech gedilosson. This is the accepted minhag today, as we constantly use imported arva minim. (See however, Pninney Halacha on Mesivtah-Suka 45b for a dissenting view)
Horav Shlomo Miller's Shlit"a opinion is that indeed on the Moon you would hold them in the normal way you are standing there, regardless of where they actually grew.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit"a
Important Numbers
