On Mars or the moon where no ears of any sort are supposed to be, anything falling there (rocks from space) would not make a sound. Hmmmm. I am not convinced. It depends on what you mean by a sound.
Think of ot this way sound is a human word in human language. It refers to what we hear. Physical conditions, trees falling, etc. create the sounds. But sound is merely what we hear, not the physical conditions per se. So, certainly, when a tree falls in the forest it creates the conditions that produce sounds in our ears. Certainly any animals nearby could hear it. But if no humans are present, no human is hearing these physical conditions. Therefore no sound.
Now, we can use sensors to detect sound. For example our space craft on Mars have recorded Martian winds.
Sugar and tea blends easily, so does sand and dirt. Different airs too, but if you could look at sugar and tea and the other things, would their different atoms still be apart?
Is this science?
Yes! It is your personal, every day science. I call it the loguc of everyday life! Keep on keeping on!