The largest craters in Elysium Planitia are Eddie, Lockyer, and Tombaugh. The planitia also has river valleys—one of which, Athabasca Valles may be one of the youngest on Mars. On the north east side is an elongated depression called Orcus Patera, and this and some of the eastern plains were imaged in the 1965 Mariner 4 flyby.
A 2005 photo of a locale in Elysium Planitia at 5°N, 150°E by the Mars Express spacecraft shows what may be ash-covered water ice. The volume of ice is estimated to be 800 km (500 mi) by 900 km (560 mi) in size and 45 m (148 ft) deep, similar in size and depth to the North Sea. The ice is thought to be the remains of water floods from the Cerberus Fossae fissures about 2 to 10 million years ago. The surface of the area is broken into 'plates' like broken ice floating on a lake (see below). Impact crater counts show that the plates are up to 1 million years older than the gap material, showing that the area solidified much too slowly for the material to be basaltic lava.
NASA'sInSight mission landed on Elysium Planitia on November 26, 2018. It took off from Earth on the 5th May 2018. The probe will study the internal structure of Mars and by so doing improve understanding of the planet's evolution. InSight Mars lander was able to take color pictures from the surface Elysium Planitia and sent them by radio signal back to Earth. During the descent sequence two additional items were jettisoned, the backshell with parachute, and heat shield, and they impacted in the vicinity of the lander.
First images of Elysium Planitia from InSight's Instrument Context Camera (ICC, left), without lens cover and stretched (ICC, Middle), and the Instrument Deployment Camera (IDC, right)
^Golombek, M.; et al. (2017). Selection of the 2018 Insight Landing Site. 48th Lunar and Planetary Science Conference. 20–24 March 2017. The Woodlands, Texas. Bibcode:2017LPI....48.1515G. LPI Contribution No. 1964, id.1515.