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  • Here is rotating globe of Mars and we're going to zoom in on the middle Southern latitudes,

  • the part of Mars where we find these active slope features, and we're zooming in on the

  • Newton Basin crater here. What you can see are lots of gullies. The

  • active features that we've recently discovered are on the slopes that are facing mostly to

  • the North to the equator. What we see are much smaller scale features

  • than gullies. You can see_an area of bedrock, a steep cliff here, and it's from that bedrock

  • that these dark features flow out. Given the latitude and the slope aspect and

  • particular the temperatures, it suggests that there's a volatile involved here and the appropriate

  • volatile for this temperature is water, probably salty water because sometimes these are active

  • when it's a little bit below the freezing point of pure water, salt lowers the melting

  • point. And water on Mars should be salty; we know there's lots of salts on Mars.

  • This is potentially actual water, in the liquid state, flowing on Mars today not millions

  • of years ago. In late spring and into the summer is when these features form and fade.

  • By late summer - early fall they'll be completely gone and we'll see just a normal looking slope

  • throughout the winter. Every place where we have multiple years these

  • features recurr. They're not exactly the same, they may be

  • more or less active one year than another but they keep coming back.

Here is rotating globe of Mars and we're going to zoom in on the middle Southern latitudes,

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火星上發現的水流 (Water Flows Discovered on Mars)

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    Jack 發佈於 2021 年 01 月 14 日
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