InSight touched down on Mars at 11:52:59 a.m. PT on November 26, 2018.
NASA’s InSight has sent signals to Earth indicating that its solar panels are open and collecting sunlight on the Martian surface. NASA’s Mars Odyssey orbiter relayed the signals, which were received on Earth at about 5:30 p.m. PST (8:30 p.m. EST). Solar array deployment ensures the spacecraft can recharge its batteries each day. Odyssey also relayed a pair of images showing InSight’s landing site.
NASA’s InSight Mars lander acquired this image using its robotic arm-mounted, Instrument Deployment Camera (IDC). This image was acquired on November 26, 2018, Sol 0 where the local mean solar time for the image exposures was 14:04:35. Image Credit: NASA/JPL-Caltech
The panels are modeled on those used with NASA’s Phoenix Mars Lander, though InSight’s are slightly larger in order to provide more power output and to increase their structural strength. These changes were necessary to support operations for one full Mars year (two Earth years). In the coming days, the mission team will unstow InSight’s robotic arm and use the attached camera to snap photos of the ground so that engineers can decide where to place the spacecraft’s scientific instruments. It will take two to three months before those instruments are fully deployed and sending back data.
In the meantime, InSight will use its weather sensors and magnetometer to take readings from its landing site at Elysium Planitia — its new home on Mars.
What’s In a Name?
A dictionary definition of “insight” is to see the inner nature of something. The mission of InSight is to see inside Mars and learn what makes it tick. So while InSight is the first Mars mission dedicated to studying the planet’s deep interior, it is more than a Mars mission, because information about the layers of Mars today will advance understanding about the formation and early evolution of all rocky planets, including Earth. Although Mars and Earth formed from the same primordial stuff more than 4.5 billion years ago, they became quite different. InSight will help explain why.
A planet’s deep interior holds evidence related to details of the planet’s formation that set the stage for what happens on the surface. The interior heat engine drives the processes that lift some portions of the surface higher than others, resulting in a landscape’s elevation differences. The interior is the source of most of a planet’s atmosphere, its surface rocks, water and ice, and its magnetic field. It provides many of the conditions that determine whether a planet will have environments favorable for the existence of life.
Why This Kind of Investigation of Mars?
Several reports setting scientific priorities for planetary science have stressed the importance of investigating the interior of Mars. While the Mars Viking missions of the 1970s were still active, a report by the National Research Council’s Committee of Planetary and Lunar Exploration, Strategy for Exploration of the Inner Planets: 1977-1987, said, “Determination of the internal structure of Mars, including thickness of a crust and the existence and size of a core, and measurement of the location, size and temporal dependence of Martian seismic events, is an objective of the highest importance.”
In ensuing decades, several missions for investigating Mars’ interior were proposed, though none flew successfully. The National Research Council’s most recent decadal study of planetary-science priorities, Vision and Voyages for Planetary Science in the Decade 2013-2022, said, “Insight into the composition, structure and history of Mars is fundamental to understanding the solar system as a whole, as well as providing context for the history and processes of our own planet. …Unfortunately, there has been little progress made toward a better understanding of the martian interior and the processes that have occurred.”
A stationary lander capable of placing sensitive instruments directly onto the surface and monitoring them for many months is a mission design exactly suited to studying the interior of Mars. InSight will be the first Mars mission to use a robotic arm to grasp objects (in this case, scientific instruments) and permanently deploy instruments onto the ground. The mission has no need for a rover’s mobility. The heat probe and seismometer stay at a fixed location after deployment. The precision of the geodesy investigation gains from keeping the radio in one place.
Mars Surface Operations
InSight’s surface operations phase will start one minute after touchdown. The prime mission will operate on the surface for one Martian year plus 40 Martian days, or sols, until Nov. 24, 2020. Some science data will be collected beginning the first week after landing, but the mission’s main focus during that time is preparing to set InSight’s instruments directly on the Martian ground.
Placement of instruments onto the ground is expected to take about 10 weeks. Sinking the heat probe to full depth is expected to take about seven weeks further. After that, the lander’s main job will be to sit still and continue collecting data from the instruments.
InSight will rely on battery-stored energy as it descends through the atmosphere and until the lander’s solar arrays can be opened after touchdown, so deploying the arrays is a crucial early activity. However, the lander will first wait about 16 minutes to let any dust from the landing settle, in order to avoid having the dust settle onto the arrays’ photovoltaic cells. During those minutes, the motors for unfurling the arrays will begin warming in preparation. The two arrays will take a few minutes to fully deploy, beginning about 25 minutes after touchdown to allow sufficient warming of the motors.
Tasks on landing day will be programmed to be performed autonomously, without any need for the lander to receive communication from the InSight team on Earth. The landing-day activities other than deploying the solar arrays will include checking the lander’s health indicators, taking a wide-angle image toward the south, and powering down to “sleep” mode for the first night on Mars.
InSight has two official overarching science goals:
1) Understand the formation and evolution of terrestrial planets through investigation of the interior structure and processes of Mars;
2) Determine the present levels of tectonic activity and meteorite-impact activity on Mars.
- To get to these goals, NASA has determined these more specific science objectives:
– the thickness and structure of the crust
– the composition and structure of the mantle
– the size, composition, and physical state of the core
– the thermal state of the interior
– the rate and geographic distribution of seismic activity
– the rate of meteorite impacts on the surface