all right, welcome back, i'm fredricka whitfield. it's been more than 14 years since a mission to mercury has taken place. all that changed today when a space probe launched to the tiniest planet in our solar system to gather information on its composition, atmosphere and geophysics. here's cnn's robyn kurnow. >> reporter: it has a long journey ahead. 8 million kilometers to be exact. this spacecraft is headed to mercury, the planet closest to the sun. to travel that far, scientists expect it's going to take seven years to get there and it won't be easy. >> flying around mercury is one of the most challenging spaceflight endeavors that has ever been taken. we have a very long time to get