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== Problems with uniformitarian theories ==

== Problems with uniformitarian theories ==

# The lack of impact craters forces evolutionists to admit that the surface of Venus appears relatively young. Scientist David Grinspoon suggests that "something dramatic happened on Venus which wiped out almost all signs of an older surface."<ref name=Bortman/> This, Grinspoon says, happened 600 or 700 million years ago. Venus has little to no wind, and any surface liquid water assumed by scientists would have long since evaporated. Therefore the youthful appearance of the surface remains very difficult to explain.

# The lack of impact craters forces evolutionists to admit that the surface of Venus appears relatively young. Scientist David Grinspoon suggests that "something dramatic happened on Venus which wiped out almost all signs of an older surface."<ref name=Bortman/> This, Grinspoon says, happened 600 or 700 million years ago. Venus has little to no wind, and any surface liquid water assumed by scientists would have long since evaporated. Therefore the youthful appearance of the surface remains very difficult to explain.

# Grinspoon also assumes, without discernible warrant, that Venus once had liquid-[[water]] oceans that have since evaporated.<ref name=Bortman/> Their sole grounds for so stating is that if Earth formed with such vast surface oceans, so Venus should have. Yet the atmosphere has no more than 20 ppm of water today. Moreover, the extensive explorations of Venus by both orbiters and landers has revealed no geological evidence that Venus ever had an ocean. (The conventionale explanation is that the resurfacing of Venus alluded to above would have destroyed any such evidence.)

# Grinspoon also assumes, without discernible warrant, that Venus once had liquid-[[water]] oceans that have since evaporated.<ref name=Bortman/> Their sole grounds for so stating is that if Earth formed with such vast surface oceans, so Venus should have. Yet the atmosphere has no more than 20 ppm of water today. Moreover, the extensive explorations of Venus by both orbiters and landers has revealed no geological evidence that Venus ever had an ocean. (The conventionale explanation is that the resurfacing of Venus alluded to above would have destroyed any such evidence.)

# Venus rotates retrograde to its orbit around the Sun. Nearly every other Solar System body rotates prograde. This presents a serious theoretical problem for the [[nebular hypothesis]] of the origin of the solar system. The usual suggested solution is a giant impact, or a series of impacts, that somehow reversed Venus' direction. But such models must also explain why these impacts left Venus in an almost circular orbit and with an axis tilted less than three degrees from being perpendicular to its orbital plane.

# Venus rotates retrograde to its orbit around the Sun. Nearly every other Solar System body rotates prograde. This presents a serious theoretical problem for the [[nebular hypothesis]] of the origin of the solar system. The usual suggested solution is a giant impact, or a series of impacts, that somehow reversed Venus' direction. But such models must also explain why these impacts left Venus in an almost circular orbit and with an axis tilted less than three degrees from being perpendicular to its orbital plane.