Unearthing Mars' Mysteries: A Deep Dive into NASA's InSight Mission

NASA’s InSight mission, an abbreviation for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, was a groundbreaking endeavor aimed at exploring and understanding the mysterious "inner space" of Mars. This mission, a first of its kind, was designed to study the Red Planet's crust, mantle, and core, revealing insights about the early formation and evolution of terrestrial planets in our solar system.

This article seeks to explore the various aspects of this ambitious project, from its inception to its scientific goals, and the groundbreaking data it has gathered so far.

The Genesis of the InSight Mission

InSight’s journey began as one of the 28 submissions for NASA's Discovery Program in 2010. This program was designed to fund highly focused science missions that sought to answer critical questions in solar system science. The initial proposal for InSight, referred to as the Geophysical Monitoring Station (GEMS), was selected as a finalist alongside two other proposals - Titan Mare Explorer and Comet Hopper, each receiving $3 million to perform a concept study.

Lockheed Martin hosted the InSight's solar wing test at its cleanroom in Denver. (Image Credit: NASA Mars Insight Mission)

In August 2012, InSight was selected for the next launch, marking the beginning of its construction in May 2014. Lockheed Martin Space Systems took the responsibility of building the spacecraft, basing it on the successful design from the 2007 Phoenix mission while incorporating the latest avionics technology and advanced science instruments.

The Journey to Mars

InSight embarked on its interstellar journey on May 5, 2018, launched from Vandenberg Air Force Base in California onboard an Atlas V vehicle from United Launch Alliance. It successfully landed on November 26, 2018, in the Martian Elysium Planitia. This equatorial zone, located just south of an ancient volcanic area, provided the perfect base for InSight to carry out its mission.

Alongside InSight, two mini-spacecraft, Mars Cube One, or MarCO, were launched. These briefcase-sized CubeSats, the first to travel into deep space, were part of a separate NASA technology experiment. Their goal was to test new miniaturized deep space communication equipment, which, if successful, could offer new capabilities to future missions.

The InSight Lander and Its Instruments

The InSight Lander, a stationary probe, was designed to withstand the harsh entry into Mars' atmosphere. The protective heat shield had to endure temperatures of 2,800 degrees Fahrenheit before deploying a parachute to reduce the descent rate. The descent engines then took over to ensure a propulsive landing at a speed of just 5 ½ miles per hour.

The lander was equipped with cutting-edge instruments designed to delve deep beneath the surface and seek the fingerprints of the processes that formed the terrestrial planets. It tracked the planet's "vital signs" - its "pulse" (seismology), "temperature" (heat flow), and "reflexes" (precision tracking).

InSight had three primary instruments: the Seismic Experiment for Interior Structure (SEIS), the Heat Flow and Physical Properties Probe (HP3), and the Rotation and Interior Structure Experiment (RISE). Each instrument plays a crucial role in achieving the mission's scientific goals.

Scientific Goals of the InSight Mission

InSight’s mission was to uncover how a rocky body forms and evolves to become a planet by investigating the interior structure and composition of Mars. The mission's primary science objectives were to understand the formation and evolution of terrestrial planets through the investigation of the interior structure and processes of Mars, and determine the present level of tectonic activity and meteorite impact rate on Mars.

An animation of NASA's InSight probe attempting to land on the surface of Mars. (Image Credit: Lockheed Martin)

Unlike previous missions that investigated the surface history of Mars by examining features like canyons, volcanoes, rocks, and soil, InSight's goal was to uncover the signatures of the planet's formation that can only be found by studying its "vital signs" far below the surface.

InSight's Findings

In early 2019, InSight began detecting and recording marsquakes, providing the first direct seismic observations on Mars. These seismic events were similar to tectonic activities on Earth, providing clues about Mars' internal composition and structure. Researchers extrapolated data from these marsquakes to determine the average thickness of Mars' crust, which lies between 24 and 72 kilometers.

Further investigations revealed the structure of Mars' mantle, which extends to a depth of nearly 800 kilometers, suggesting that a thick lithosphere lies close to 500 kilometers below the surface. The findings also suggested that Mars' crustal layer is highly enriched in heat-producing radioactive elements, which heats this region at the expense of the planet's interior.

The mission also uncovered details about the Martian core. Researchers found that Mars' relatively large liquid metal core has a radius of nearly 1,830 kilometers, beginning roughly halfway between the surface and the center of the planet. This suggested that the planet's mantle consists of only one rocky layer, rather than two, like on Earth.

The End of the InSight Mission

While InSight was initially slated to send back data about the Red Planet's interior for about 1 Mars year (728 Earth-days), NASA has extended the mission through December 2022, where it has concluded. In its first year on Mars, InSight returned information on marsquakes, possible models for the core of the planet, and the tiny wobbles in the planet's orbit.

Despite facing challenges such as the unexpectedly hard Martian soil, which prevented the lander's mole-like robot attachment from drilling its way under the surface, the mission continued to provide valuable data that will refine our understanding of Mars and its enigmatic mysteries.

“We broke new ground, and our science team can be proud of all that we’ve learned along the way," said the principal investigator of InSight’s seismometer - Philippe Lognonné - in a statement.

The InSight mission represents a significant step forward in our understanding of the Red Planet. By studying the interior of Mars, InSight helped us understand the formation and evolution of terrestrial planets, including our own.