Are cell mutations always bad? A mutation is a change in the genetic material of an organism. We are made from trillions of cells, each with a nucleus composed of DNA â a set of instructions that tells the cell what to do. Cells copy themselves with astonishing accuracy, but every now and then a piece of code is copied incorrectly.
Seven eclipses occur in a minimum of 12 lunar months (about 354.37 days). Given that the calendar year is only about eleven days longer than 12 lunar months, the first of the seven eclipses has to come in early January for the seventh eclipse to occur before the end of the year.
Best Answer: Its amazing what you can learn if you read about this. Total lunar eclipses only occur when the moon is on the side of the Earth directly opposite the sun (it appears as a full moon). Full moon occurs every 29.5 days (about once a month). But the moon doesn't orbit the Earth in the same plane as the sun appears, so there are many times when the moon is either above or below that direct line with the sun - the moon misses Earth's shadow. Total solar eclipses ANYWHERE are more rare than lunar eclipses: - the moon has to be directly in line with the sun.