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.
A partial eclipse occurs when the moon covers only part of the sun. Only partial eclipses will occur in 2018. The first solar eclipse of 2018 will take place on Feb. 15. But it will be visible only from parts of Antarctica, the Atlantic Ocean and southern South America.