NASA’s Mars Exploration Program is a science-driven, technology-enabled study of Mars as a planetary system in order to understand:

• the formation and early evolution of Mars as a planet
• the history of geological and climate processes that have shaped Mars through time
• the potential for Mars to have hosted life (its “biological potential”)
• the future exploration of Mars by humans, and
• how Mars compares to and contrasts with Earth.

Timeline:

•   MARS 2020 PERSEVERANCE (rover): It is searching for signs of past microbial life and has a drill that collects core samples from mars.

•   INSIGHT (lander) 2018: InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) is a terrestrial planet explorer.

•   EXOMARS (orbiter/lander) 2016: ESA's Trace Gas Orbiter acts as communications relay support for landers and rovers on the Martian surface. The demonstration module lander was lost on touchdown.

•   MAVEN (orbiter) 2015: (Mars Atmospheric and Volatile EvolutioN) is obtaining critical measurements of the Martian atmosphere to help understand drastic climate change on Mars over its history.

•   CURIOSITY (rover) 2012: Curiosity's scientific tools found chemical and mineral evidence of past habitable environments on Mars.

•   PHOENIX SCOUT (lander) 2008: High-resolution perspective of the landing site's geology. Prodded range maps and identified local minerals.

•   MARS RECONNAISSANCE ORBITER (orbiter) 2005: Detailed view of the geology and structure of Mars, identifying obstacles that could jeopardize the safety of future landers and rovers.

•   SPIRIT & OPPORTUNITY (rovers): 2004

•   MARS EXPRESS (orbiter): 2004

•   MARS ODYSSEY (orbiter) 2001: Measurements to create maps of minerals and chemical elements and identified regions with buried water ice.

•   MARS POLAR LANDER (lander) 1999: Lost on arrival.

•   DEEP SPACE 2 (probe) 1999: Lost on arrival.

•   MARS CLIMATE ORBITER (orbiter) 1998: Lost on arrival.

•   PATHFINDER (rover) 1996: Returned images from the lander and rover, chemical analyses of rocks and soil, data on winds and other weather factors.

•   MARS GLOBAL SURVEYOR 1996: Studied Martian surface, atmosphere and interior.

•   MARS OBSERVER (orbiter) 1992: Communication lost prior to orbit insertion.

•   VIKING 1 & 2 (orbiter & lander) 1975: NASA's Viking Project was the first U.S. mission to land a spacecraft safely on the surface of Mars and return images of the surface.