The existence of comets poses a problem for cosmic Evolution. Comets are effectively giant balls of dirty ice hurtling through space. They're not very stable, losing material at a high rate, especially when they approach the sun. Short period comets complete an orbit around the sun in 200 years or less, and couldn't survive more than 100 trips around the sun. If the entire universe is around 6,000 years old, this isn't a problem. If, however, our solar system is 5billion years old, comets don't make sense.
Oort clouds have been proposed as a rescuing device. According to legend, we still have short period comets because of these magical oort clouds that are producing these comets. The problem? Evolutionists have as much evidence for oort clouds as they claim we have for God: none. The only reason to believe in anything as fanciful as an oort cloud is the fact that thousands of comets still exist, to the detriment of cosmic Evolution theory. I simply don't have enough imagination to believe in such fairy tales. Until Evolutionists prove the existence of oort clouds, Christians have no reason to answer them. Comets remain just one more piece of evidence against magical explosions, millions of years and random chance.