Pictured: An Ancient Martian . ... Alien? ... The tube-like form on the above highly magnified image is now believed by many to be a fossil of a simple Martian organism that lived over 3.6 billion years ago . ... A reconstruction of events indicates that the meteorite that housed this potential fossil was catapulted from Mars during a huge impact 16 million years ago and fell to Earth's Antarctica only 13,000 years ago. ... NASA's current missions to Mars are Mars Global Surveyor and Mars Pathfinder . ...