Image of a spacecraft during entry of Mars



Compared with Phoenix, though, InSight's landing presented four added challenges:

  • InSight entered the atmosphere at a lower velocity -- 12,300 miles per hour (5.5 kilometers per second) vs. 12,500 miles per hour (5.6 kilometers per second).
  • InSight had more mass entering the atmosphere -- about 1,340 pounds (608 kilograms) vs. 1,263 pounds (573 kilograms).
  • InSight landed at an elevation of about 4,900 feet (1.5 kilometers) higher than Phoenix did, so it had less atmosphere to use for deceleration.
  • InSight landed during northern hemisphere autumn on Mars, when dust storms are known to have grown to global proportions in some prior years.


  • InSight used a thicker heat shield, partly to handle the possibility of being sandblasted by a dust storm.
  • InSight’s parachute suspension lines used stronger material.


  • Entry - The spacecraft was controlled by small rockets during descent through the Martian atmosphere, toward the surface.
  • Parachute Descent - The InSight spacecraft slowed using a large parachute, jettisoned its heat shield and extended its three shock-absorbing legs.
  • Powered Descent - Once the lander separated from its backshell and parachute, 12 descent engines on the lander began firing and the onboard guidance software slowed down the spacecraft until touchdown.