Aside from the monthly phases of the moon, there is also a daily lunar effect on fish feeding habits. Moonrise and moonset appear to be very good times to go fishing, if other factors like the weather are cooperative. Studies show that fish are more active 90 minutes before and after either the moonrise or moonset. Given this, you now know when is a good time to go fishing, provided it fits your schedule! The moon and fishing are forever tied together and you can learn what you need to know with nothing more than a little research. That's right folks, it won't cost you one red cent to learn the information that you need to know about the moon and fishing. All you have to do is invest a little bit of time and you'll be good to go. There's no need to take the equivalent of a college course on this subject, just a little time will do. 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.