<story><title>Photos from NASA&apos;s Perseverance rover indicate ancient flash floods on Mars</title><url>https://www.science.org/doi/10.1126/science.abl4051</url></story><parent_chain><item><author>harwoodleon</author><text>I was watching the ISS live feed going over North West Africa and up to Italy. The landscape was red and arid and it struck me just how ‘Mars like’ it looked.&lt;p&gt;It got me thinking that Earth could be facing the same destiny many aeons from now. It’s hard to imagine with the amount of H2O on the planet right now, but if it can happen to Mars (the atmosphere is stripped away), it could happen here I suppose.&lt;p&gt;But I wonder if a Venus situation is more likely first, because of our proximity to the Sun?&lt;p&gt;This discovery certainly makes me feel that lifecycle of planets is an awesome thing.</text></item></parent_chain><comment><author>cletus</author><text>It&amp;#x27;s not even a question: the Earth is absolutely facing the same fate. The Sun is getting hotter and in ~1 billion years the Earth will be uninhabitable by us in its current form.&lt;p&gt;Eventually (~4-5B years) the Sun will expand while in its dying stages and probably swallow the Earth.&lt;p&gt;What can we do? That&amp;#x27;s actually quite &amp;quot;easy&amp;quot;. I mean &amp;quot;easy&amp;quot; in the essence that no weird new physics is required, it&amp;#x27;s just an engineering problem, albeit a massive one. Then again, we have a lot of time. So there are essentially three things we can do:&lt;p&gt;1. Reduce the amount of light and heat hitting the Earth. Example: large arrays of solar power collectors at the L1 Lagrange point. If the Sun is 10% hotter in 1B years and you reduce the light hitting the Earth by ~10% it about evens out. The captured energy can be put to use and I expect it wouldn&amp;#x27;t even be noticeable from Earth. The Sun will just be slightly dimmer;&lt;p&gt;2. You can move the Earth. Many people are familiar with gravity assists for spacecraft. Obviously gravity affects both bodies but the spacecraft is so low-mass it has no discernable effect on the larger body. Imagine taking large rocks and flying them past the Earth. The net interaction can be that the Earth moves slightly faster. Do this over a long enough time frame and you can move the Earth&amp;#x27;s orbit outwards.&lt;p&gt;3. The Sun itself can be manipulated to remove mass from it, particularly Helium.&lt;p&gt;A lot can be done in a billion+ years.</text></comment>
<story><title>Photos from NASA&apos;s Perseverance rover indicate ancient flash floods on Mars</title><url>https://www.science.org/doi/10.1126/science.abl4051</url></story><parent_chain><item><author>harwoodleon</author><text>I was watching the ISS live feed going over North West Africa and up to Italy. The landscape was red and arid and it struck me just how ‘Mars like’ it looked.&lt;p&gt;It got me thinking that Earth could be facing the same destiny many aeons from now. It’s hard to imagine with the amount of H2O on the planet right now, but if it can happen to Mars (the atmosphere is stripped away), it could happen here I suppose.&lt;p&gt;But I wonder if a Venus situation is more likely first, because of our proximity to the Sun?&lt;p&gt;This discovery certainly makes me feel that lifecycle of planets is an awesome thing.</text></item></parent_chain><comment><author>mixmastamyk</author><text>The much larger mass, gravity,  and magnetic field of Earth prevents large scale atmospheric losses.  Whether we have the resources to ignite another Venus remains to be seen.</text></comment>