更多"Time was when the solar system had "的相关试题:
[简答题]Time was when the solar system had two watery worlds. 46) Directly next door to the warm. wet, loamy Earth was the warm, wet, loamy Mars, both planets covered with oceans and running with rivers-and both possibly teeming with life. Billions of years ago, however, the low-gravity Mars had both its air and water leak away, causing the planet to become the dead, freeze-dried place it is today.
That is what the prevailing thinking has been. Now, it appears that thinking may be wrong. 47) Recently, NASA released new images from the Mars Global Surveyor spacecraft that suggest water may be flowing up and streaming onto the Martian surface-dramatically increasing the likelihood that at least part of the planet is biologically alive. "If these results prove true," says Ed Weiler, associate administrator of NASA’s Office of Space Science, "[they have] profound implications for the possibility of life."
Finding liquid water on Mars’ surface has never been easy-because it