Editing Mars Direct (section)

==Alternatives==
"[[Mars to Stay]]" proposals involve not returning the first immigrant/explorers immediately, or ever. It has been suggested the cost of sending a four or six person team could be one fifth to one tenth the cost of returning that same four or six person team. Depending on the specific approach taken, a quite complete lab could be sent and landed for less than the cost of sending back even 50 kilos of Martian rocks. Twenty or more persons could be sent for the cost of returning four.<ref>{{Cite web|url=https://www.universetoday.com/19962/aldrin-mars-pioneers-should-not-return-to-earth/|title=Aldrin: Mars Pioneers Should Not Return to Earth|first=Ian|last=O'Neill|date=October 23, 2008}}</ref>