"For the smaller craters, it's like if you're filling a bucket, eventually your bucket gets full, but if you keep pouring cups of water into the bucket, you can't tell how many cups of water beyond full you've gone. Looking at the larger craters at the subsurface might give us insight, because that 'bucket' isn't full yet," Dr. Soderblom added.
Dr. Soderblom calculated the gravity signatures both in and around 1,200 craters that had been excavated by impacting objects on the lunar far side. He then went on to compare the gravity within each crater with the gravity of the surrounding terrain. Dr. Soderblom did this in order to determine whether an impact increased or decreased the local porosity.
We all have learned through School that the Moon is what affects the tides by its gravitational pull on the earth. Well the gravitational pull of the moon not only impacts the changing tides it impacts the activity of fish also.