Exploration of Mars through history

Engineers observed the first driving test for the Perseverance rover in a clean room at NASA's Jet Propulsion Laboratory in Pasadena, Calif., on December 17, 2019. Photo courtesy of NASA

Much of Mars is covered by sand and dust, but in some places, stacks of sedimentary layers are visible. In this image, exquisite layering is revealed emerging from the sand in southern Holden Crater. Sequences like these offer a window into Mars' complicated geologic history. Holden Crater once was a candidate landing area for the Curiosity Mars science laboratory, and still is an intriguing choice today. Photo courtesy of NASA

Engineers and technicians insert 39 sample tubes into the belly of the rover at the Kennedy Space Center on May 20, 2020. NASA's upcoming Perseverance rover mission will collect the first samples from another planet for return to Earth by subsequent missions. In place of astronauts, the Perseverance rover will rely on the most complex, capable and cleanest mechanism ever to be sent into space, the Sample Caching System. Each tube is sheathed in a gold-colored cylindrical enclosure to protect it from contamination. Perseverance will carry 43 sample tubes to the Red Planet's Jezero Crater. Photo courtesy of NASA

This NASA artist's concept depicts the Ingenuity Mars helicopter, which was prepared for launch from Florida in summer 2020, on the surface of Mars. Image courtesy of NASA

The Perseverance rover undergoes processing at a payload servicing facility at NASA's Kennedy Space Center on February 14, 2020. Initial processing took place on February 13, one day after a C-17 aircraft, with the rover aboard, touched down at the Launch and Landing Facility at the space center. Photo courtesy of NASA

The head of the Perseverance rover's remote sensing mast is seen in the Spacecraft Assembly Facility's High Bay 1 at the Jet Propulsion Laboratory in Pasadena, Calif., on July 23, 2019. The rover contains an armada of imaging capabilities, from wide-angle landscape cameras to narrow-angle, high-resolution zoom lens cameras. Photo courtesy of NASA

The Opportunity rover used its navigation camera for this northward view of tracks the rover left on a drive from one energy-favorable position on a sand ripple to another in 2010. NASA announced on February 13, 2019, that one of the most successful and enduring feats of interplanetary exploration was at an end after almost 15 years exploring the surface of Mars. The Opportunity rover stopped communicating with Earth when a severe Mars-wide dust storm blanketed its location in June 2018. Photo courtesy of NASA

The Curiosity rover finds an ancient oasis of a network of cracks in this Martian rock slab called "Old Soaker" that might have formed from the drying of a mud layer more than 3 billion years ago. The view spans about 3 feet, left to right, and combines three images taken by the MAHLI camera on the arm of Curiosity rover. Photo courtesy of NASA/JPL-Caltech/MSSS

The small spherules on the Martian surface in this close-up image are near Fram Crater, visited by the Opportunity rover during the 84th Martian day, or sol, of the rover's work on Mars on April 19, 2004. The area shown is 1.2 inches across. These are examples of the mineral concretions nicknamed "blueberries." Opportunity's investigation of the hematite-rich concretions during the rover's three-month prime mission in early 2004 provided evidence of a watery ancient environment. Photo courtesy of NASA

The Opportunity rover's shadow was photographed by the rover's front hazard-avoidance camera as the rover moved farther into Endurance Crater in the Meridiani Planum region of Mars on July 26, 2004. Photo courtesy of NASA

This scene from the panoramic camera (Pancam) on the Opportunity rover looks back toward part of the west rim of Endeavour Crater that the rover drove along, heading southward, during the summer of 2014. The vista merges multiple Pancam exposures taken on August 15, 2014, during the 3,754th Martian day of Opportunity's work on Mars. Photo courtesy of NASA

Mars InSight team members Kris Bruvold (L) and Sandy Krasner react after receiving confirmation that the Mars InSight lander successfully touched down on the surface of Mars. They are inside the Mission Support Area at NASA's Jet Propulsion Laboratory in Pasadena, Calif., on November 26, 2018. InSight, short for Interior Exploration Using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars -- its crust, mantle and core. Photo by Bill Ingalls/NASA

This image was acquired by the High Resolution Imaging Science Experiment (HiRISE) camera aboard the Mars Reconnaissance Orbiter on April 18, 2017. A close-up in enhanced color produces a striking effect, giving the impression of a cloud-covered cliff edge with foamy waves crashing against it. The reality is that the surface of Mars is much dryer than our imaginations might want to suggest. This is only a tiny part of a much larger structure -- a crater that has been infilled by material more resistant to erosion than the rocks around it, surrounded by bluish basaltic dunes. The edge of these elevated, light-toned deposits are degraded, irregular and cliff-forming. Photo courtesy of NASA

The foreground of this scene from the mast camera on the Curiosity rover shows purple-hued rocks near the rover's late-2016 location on lower Mount Sharp. The scene's middle distance includes higher layers that are future destinations for the mission. Photo courtesy of NASA

A new map of Mars' gravity, derived using Doppler and range tracking data collected by NASA's Deep Space Network from three NASA spacecraft in orbit around Mars -- Mars Global Surveyor, Mars Odyssey and the Mars Reconnaissance Orbiter -- is the most detailed to date, providing a revealing glimpse into the hidden interior of the Red Planet. This view of the Martian gravity map shows the Tharsis volcanoes and surrounding flexure. The white areas in the center are higher-gravity regions produced by the massive Tharsis volcanoes, and the surrounding blue areas are lower-gravity regions that might be cracks in the crust. Photo courtesy of NASA

Expedition 46 Commander Scott Kelly of NASA (C) is carried into a medical tent after he landed in the Soyuz TMA-18M spacecraft in a remote area near the town of Zhezkazgan, Kazakhstan, on March 2, 2016. Kelly completed an International Space Station record year-long mission to collect valuable data on the effect of long-duration weightlessness on the human body that will be used to formulate a human mission to Mars. Photo by Bill Ingalls/NASA

Dark narrow streaks, called "recurring slope lineae," emanate from the walls of Garni Crater on Mars, in this view constructed from observations by the HiRISE camera on the Reconnaissance Orbiter on September 28, 2015. The dark streaks are hypothesized to be formed by flow of briny liquid water on Mars. The image was produced by first creating a 3D computer model (a digital terrain map) of the area based on stereo information from two HiRISE observations, and then draping an image over the land-shape model. The vertical dimension is exaggerated by a factor of 1.5 compared to horizontal dimensions. Photo by NASA/JPL-Caltech/University of Arizona

The Opportunity rover's robotic arm, called the "instrument deployment device," at upper left, is seen as it continues to traverse Mars on November 26, 2014. Photo courtesy of NASA/JPL-Caltech

A United Launch Alliance Delta IV Heavy launches NASA's Orion Spacecraft on its "Exploration Flight Test" from Launch Complex 37 at the Cape Canaveral Air Force Station, Fla., on December 5, 2014. The unmanned mission will test the systems on NASA's newest spacecraft during a 4 1/2-hour, two-orbit flight. NASA's plans for Orion include flying future manned missions on voyages to deep space exploring asteroids and eventually Mars. Photo by Joe Marino-Bill Cantrell/UPI

The Curiosity rover uses the camera at the end of its arm in April and May 2014 to take dozens of component images combined into this self-portrait "selfie" where the rover drilled into a sandstone target called "Windjana" on the Martian surface. Most of the component frames of this mosaic view were taken during the 613th Martian day of Curiosity's work on Mars on April 27, 2014. Photo courtesy of NASA

The Mars Atmosphere and Volatile Evolution Mission (MAVEN) spacecraft undergoes final preparations at the Kennedy Space Center, Fla., on September 27, 2013. MAVEN will be launched by an Atlas 5 rocket scheduled for liftoff on November 18, 2013. The Lockheed Martin spacecraft will orbit the planet Mars for one year after completing a 10-month journey through space. The mission is to explore how the sun has affected Mars' upper atmosphere and ionosphere. Photo by Joe Marino-Bill Cantrell/UPI

This image comparison was taken August 6, 2012 by the Hazard-Avoidance camera on the Curiosity rover before and after the clear dust cover was removed. Curiosity, which successfully landed on the Martian surface on August 6, 2012, was equipped with a host of sensors, cameras and an onboard chemistry lab. Photo courtesy of NASA/JPL-Caltech/Malin Space Science Systems

Technicians look over the the Curiosity rover during inspections at the Jet Propulsion Laboratory's NASA Mars Science Laboratory in Pasadena, Calif. Curiosity, a mobile robot for investigating Mars' past or present ability to sustain microbial life, was launched on November 26, 2011. Photo courtesy of NASA

This false-color view is the first observation of a target selected autonomously by the NASA's Mars Exploration Rover Opportunity on Mars on the 2,172nd Martian day, or sol, of its mission, March 4, 2010. NASA's Mars Exploration Rover Opportunity used newly developed and uploaded software to choose a target from a wider-angle image and point its panoramic camera to observe the chosen target through 13 different filters. Images taken through three of the filters are combined into this false-color view of the rock, which is about the size of a football. Photo courtesy of NASA

The half-mile-wide Victoria Crater in the Meridiani Planum region of Mars, photographed by the HiRISE camera on NASA's Mars Reconnaissance Orbiter, is seen on July 18, 2009. Colors have been enhanced to make subtle differences more visible. Photo courtesy of NASA/JPL-Caltech/University of Arizona

NASA's Phoenix Mars Lander's Surface Stereo Imager took this image on on June 8, 2008. It shows two trenches dug by Phoenix's Robotic Arm, each trench is about 3 inches wide. Soil from the right trench, informally called "Baby Bear," was delivered to Phoenix's Thermal and Evolved-Gas Analyzer on June 6. The trench on the left is informally called "Dodo" and was dug as a test. This view is presented in approximately true color by combining separate exposures taken through different filters of the Surface Stereo Imager. Photo courtesy of NASA/JPL-Caltech/University of Arizona/Texas A&M University

In this artist's conception, the Phoenix Mars Lander, which was launched in August 2007 as the first project in NASA's Mars Scout missions, landed on Mars on May 25, 2008. The mission's plan is to land in icy soils near the north polar permanent ice cap and explore the history of the water in these soils and any associated rocks, while monitoring polar climate.The spacecraft and its instruments are designed to analyze samples collected from up to 20 inches deep using its robotic arm. The arm extends forward in this artist's concept of the lander on Mars. Image courtesy of NASA

NASA's Hubble Space Telescope took this close-up of Mars when it was just 55 million miles away on December 17, 2007. Mars will be at its brightest on December 24, 2007 as it aligns directly opposite of the sun, and will not be as visible for another nine years.This color image was assembled from a series of exposures taken within 36 hours of Mars' closest approach with Hubble's Wide Field and Planetary Camera 2. Photo courtesy of NASA/ESA/Hubble Heritage Team

A new space explorer, Phoenix, is pictured in the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center in Florida on July 10, 2007. The Phoenix will launch aboard a Delta II rocket to Mars and will dig in the soil and ice in the arctic region of the planet. Both the rocket and spacecraft are undergoing final preparations for the mission. Photo by Kim Shiflett/NASA

Children play with a meteorite fragment from Mars at the National Air and Space Museum's Mars Day celebration in Washington on July 21, 2006. The event marks the 30th anniversary of the landing of the Viking 1 craft on the Red Planet on July 20, 1976. Photo by Eduardo Sverdlin/UPI

The Viking II Lander landed September 3,1976, some 4,600 miles from its twin, Viking I. This image from Viking II shows the boulder-strewn field of red rocks reaching to the horizon nearly 2 miles from the spacecraft on Mars' Utopian Plain. Scientists believe the colors of the Martian surface and sky in this photo represent their true colors. Photo courtesy of NASA

A Lockheed Martin Atlas V rocket launches NASA's Mars Reconnaissance Orbiter Satellite from the Cape Canaveral Air Force Station on August 12, 2005. The Orbiter will take highly detailed images of the surface of Mars after a seven-month journey to the Red Planet. Photo by Joe Marino-Bill Cantrell/UPI

The surface of Mars is seen in this photo mosaic using both visible and infrared images recorded by the Mars Odyssey Spacecraft from August 2004. Photo courtesy of NASA

Spirit reached out its arm to meet with the Martian soil for the first time on January 16, 2004. Its Microscopic Imager, one of four instruments at the end of the rover's arm, took the highest resolution image of the Martian surface to date. Throughout the mission, this instrument will act as a geologist's hand lens, providing close-up views of rocks and soils. Photo courtesy of NASA/JPL-Caltech

President George W. Bush addresses those gathered at NASA headquarters in Washington, D.C., to announce his plans to expand the space program, on January 14, 2004. The president's plans include increased funding to send humans back to the moon, and eventually, to Mars. Photo by Michael Kleinfeld/UPI

This section of the first color image from the Spirit rover has been further processed to produce a sharper look at a trail left by the one of rover's airbags. The drag mark was made after the rover landed and its airbags were deflated and retracted. Scientists have dubbed the region the "Magic Carpet" after a crumpled portion of the soil that appears to have been peeled away (lower left side of the drag mark). Rocks also were dragged by the airbags, leaving impressions and "bow waves" in the soil. The mission team plans to drive the rover to this site to look for additional clues about the composition of the Martian soil. This image was taken by Spirit's panoramic camera. Photo courtesy of NASA/JPL-Caltech/Cornell

JPL engineers played Bob Marley's "Get Up, Stand Up" in the control room as they watched new images confirming that the Spirit rover successfully stood up on its lander, a major step in preparing for egress on January 9, 2004. This image from the rover's front hazard avoidance camera shows the rover in the final stage of its stand-up process. Photo courtesy of NASA NASA/JPL-Caltech

The second of two NASA Mars Rovers is driven over staggered ramps to test the suspension's range of motion before launch. The first of the rovers, Spirit, is scheduled to land on Mars on January 3, 2003. Photo courtesy of NASA

A Boeing Delta rocket lifts off from Cape Canaveral Air Force Station in Florida, carrying NASA's Mars Rover "Spirit" on a seven-month journey to Mars on June 10, 2003. This is the first of two rovers planned to be launched to the Red Planet, signaling NASA's return after six years. Photo by Joe Marino-Bill Cantrell/UPI

This is a false-color image of the surface of Mars as taken by the Mars Orbiter Laser Altimeter, an instrument aboard NASA's Mars Global Surveyor and released on May 27, 1999. It is the first 3D imagery of the Red Planet. This high-resolution map represents 27 million elevation measurements gathered in 1998 and 1999. The massive Hellas impact basin in the Southern Hemisphere, lower left, is nearly 6 miles deep and 1,300 miles across, and is surrounded by a ring of material that rises 1.25 miles and stretches 2,500 miles from the basin center. Photo courtesy of NASA

Astronomers using NASA's Hubble Space Telescope has discovered an enormous cyclonic storm system raging in the northern polar regions of Mars on May 19, 1999. Nearly four times the size of the state of Texas, the storm is composed of water ice clouds like storm systems on Earth, rather than dust typically found in Martian storms. This image has been processed to bring out additional detail in the storm's spiral cloud structures. Photo by Jim Bell, Steve Lee, Mike Wolff/NASA

Former Astronaut Edwin "Buzz" Aldrin Jr., the second man on the moon, stands besides a full-scale model of the Mars Viking I Lander with its digging arm extending to the surface, in Pasadena, Calif., on July 28, 1976. UPI File Photo

On July 20, 1976, at 8:12 a.m. EDT, NASA received the signal that the Viking I Lander successfully reached the Martian surface. This major milestone represented the first time the United States successfully landed a vehicle on the surface of Mars, collecting an overwhelming amount of data that would soon be used in future NASA missions. Upon touchdown, Viking I took its first picture of the dusty and rocky surface and relayed the historic image back to Earthlings eagerly awaiting its arrival. Viking I, and later Viking II Orbiter, collected an abundance of high-resolution imagery and scientific data, blazing a trail that will one day take humans to Mars. Photo courtesy of NASA