Since the 1960s, robot spacecraft have made repeated visits to Mars’ surface and orbit. Their findings revealed a planet featuring mountains, canyons, and the largest volcano in our solar system.
Rovers such as Spirit and Opportunity explored rocks to gain insight into what composes this world and to look out for signs of water.
Spirit
Two decades ago, Spirit and Opportunity made history on Mars by landing separately at different equatorial locations on its surface. Their original mission plan called for them to last only 90 days while covering only 0.4 miles (0.6 kilometers). But both solar-powered rovers far exceeded expectations by exceeding them!
Scientists were delighted to discover traces of water on Mars. A trench dug by Spirit’s right front wheel revealed an opalescent patch of silica which scientists suspect may have formed in hot springs or fumaroles — two environments on Earth known for harboring microbiology.
Opportunity also discovered hematite on Mars’ opposite side, suggesting there may be water present. These and other discoveries led scientists to conclude that at some time in its past Mars had a humid, warm environment with volcanic explosions, flowing rivers, and steam vents.
Opportunity
NASA engineers at JPL had sent over 1000 commands in an attempt to save Opportunity as the storm continued engulfing Mars, yet hope seemed increasingly distant.
Opportunity has produced significant evidence supporting its mission’s key hypothesis – that ancient water once flowed across Mars’ surface – by discovering hematite and mineral crystals within niches that contained sulfates. Furthermore, Opportunity discovered much about Mars’ geologic history through analyzing rocks and soil at all sizes of craters including Endeavour’s.
Opportunity, located in the northwest corner of Gale Crater, used its rock-abrasion tool to clear away layers of dust at Pillinger Point in March 2014. A selfie taken that month showed relatively clean surfaces; increasing chances of recharge. Unfortunately, Opportunity lost power again later that summer, ending its historic journey.
Curiosity
Curiosity, an advanced robot field geologist sent to Mars by NASA, was designed to examine whether life ever existed on that planet and test technology that may aid human exploration of Mars.
This rover has detected signs of life’s building blocks as well as evidence of water on our planet’s surface, while also offering samples for testing purposes and collecting samples with its drill. Spirit and Opportunity both serve a larger scientific mission; Curiosity stands apart with its larger, more durable footprint and more comprehensive scientific mission.
Entry, Descent and Landing System — featuring rocket-powered parachutes and an impressive heat shield — was unrivaled and has served as a model for future missions carrying heavier payloads to Mars. Mars Atmosphere and Volatile Evolution spacecraft (MAVEN) studied how atmospheric loss happened while simultaneously relaying communications from surface missions back to Earth.
MAVEN
NASA’s MAVEN (Mars Atmosphere and Volatile EvolutioN) mission will conduct its first survey of atmospheric gas loss from Mars into space. The $485 million endeavor aims to give scientists insight into its transition from once hosting liquid water for habitability into its current cold, inhospitable state.
MAVEN consists of three science instrument suites. The Particles and Fields suite, developed at Berkeley Space Sciences Laboratory by the University of California, contains six instruments which characterize solar wind, ionospheric phenomena, and their interaction with Mars’ atmosphere and magnetosphere.
MAVEN makes use of an advanced telecommunications relay system known as the Electra UHF Communications Terminal that was previously utilized on Mars missions to communicate data back from Red Planet rovers to Earth. Reaction Wheels provide navigation and attitude control while star trackers supply 10 images every second that are compared against thousands of stars in order to determine its precise orientation in space.