Greetings, all, and time for another question on life, the universe, and everything! Did you miss these? I know you did.

This week! Our topic is the terraforming of Mars! You, Zoners, are now individual little entrepreneurs, with life-extension technology, and more yes-men than you can count. Your goal? Create a new Earth. You can go about this mostly as you please, and for whatever purpose. However, there are limits to what money can buy.
• Limit #1: Your wealth is not infinite. You can't simply snap your fingers, and have the combined GDP of Europe funnel into Orion rockets. Your expenditure is limited to $50 billion a year - whatever methods you use, document how the money is used.
• Limit #2: Physics is a thing. All activities must follow the guidelines of known physics, or the strongly supported theoretical. There are no wizards here!
• Limit #3: This is a shared setting! You can either collaborate, or compete, with each other to get the job done. However, as to who is the new God-Emperor of Dune Mars, there can only be one.

Win conditions are as follows:
• Mars must have a breathable atmosphere, resembling Earth's.
• Mars must have at least 50% of it's surface volume (72,399,250 sq. km) covered with water year-round.
• At least 15,000 humans must be permanently present on the surface.
• A biosphere must exist that can replenish the global oxygen supply, and support at least 15,000 humans.

Again, feel free to build off each other's idea's but remember: the person to achieve the most results with the least effort/time spent (r=e/t) wins!

Some resources to get you started :
• Encyclopedia Astronautica - http://astronautix.com/
• Atomic Rockets -http://www.projectrho.com/public_html/rocket/index.php
• Terraforming Wiki - https://terraforming.fandom.com/wiki/Main_Page
• Orion's Arm Universe Project - https://orionsarm.com/
• Rockwell Dynamics Integrated Space Plan - https://cdn.makezine.com/uploads/2013/07/integratedspaceplan2color.pdf
• Integrated Space Analytics Integrated Space Plan - https://www.wired.com/wp-content/uploads/2015/08/ISP-5-1-9c_FINAL_30x48v2_Print1.jpg