NASA hope exploring the deep recesses of Mars will give scientists insight into the early history of Earth.
The US space agency recently gave the green light for the construction of a new lander that will examine the deep interior of the red planet.
Scientists hope learning more about the composition, layering and processes of the planet’s interior structure will also provide fresh insight into the creation of Earth-like planets, both within and beyond our solar system.
The mission, called the Interior Exploration Using Seismic Investigations, Geodesy and Heat Transport (InSight), is scheduled to launch its spacecraft from California’s Vandenberg Air Force Base in March 2016.
InSight was selected after competing against two other proposals for NASA approval and funding. One of the competing missions involved sending a spacecraft to a comet, while the other proposed sending one to one of Saturn’s moons.
Bruce Banerdt, from NASA’s Jet Propulsion Laboratory (JPL) is the mission’s principal investigator. He tells us that he and his colleagues have been working for about 20 years to convince NASA to approve their project.
Unlike the ongoing and highly successful Curiosity and Opportunity rovers that are traveling across Mars, InSight will be sent to a location near the red planet’s equator and remain stationary to conduct its scientific research.
InSight will map out the geography of the deep interior of Mars and Banerdt hopes it will provide valuable information about the composition and depth of the planet’s crust and core, as well its internal thermal characteristics, such as heat flow and energy production.
The proposed InSight landing site is labeled in white lettering. The landing sites of other current and past Mars probes are also marked. (NASA)
The spacecraft will carry a bevy of sophisticated new instruments to carry out its mission. The space agencies of Germany, France, Switzerland and the United Kingdom are providing two of the most important tools of the mission.
An international team of researchers will work together as InSight’s science team.
InSight’s mission will be made up of three main investigations, according to Banerdt.
The first is a seismometer called the Seismic Experiment for Interior Structure (SEIS), a device that will be placed on the planet’s surface to measure the shaking of the ground, mostly due to distant quakes, otherwise called marsquakes.
The advanced technology of SEIS will also analyze the seismic waves produced by the quakes sent through the interior of planet.
The interior of Mars is made up of a diverse collection of materials, such as different kinds of rock as well as iron in its core, which could be solid or liquid. The use of seismology here on Earth has allowed scientists to map out Earth’s interior in great detail, providing us with most of what we know about our planet’s core, such as that it’s made out of iron and nickel and has a liquid exterior surrounding a solid core.
The second of InSight’s three main investigations is a heat-flow probe. This device consists of a tool project members call a “mole”, which is basically a 31-centimeter self-hammering nail that will burrow down about 4 ½ to 5 meters into the planet’s surface.
Artist concept of the interior of Mars (NASA/JPL-Caltech)
As the mole makes its way beneath Mars’ surface, it will pull a string of thermocouples or heat sensors with it, which will sense the small increases in temperature as it goes further into the planet.
Banerdt says those tiny increases of temperatures will allow researchers to figure out how much heat is coming from the planet’s interior. These readings will help provide an indication as to how much of that heat is generated by radioactive decay and how fast it’s traveling up from deep within Mars and radiating out into space.
Since this heat-flow drives a lot of the planet’s geology such as volcanism, or perhaps the uplift of mountain ranges, the amount of heat developed inside of Mars will help scientists determine just how active the planet is.
The third of InSight’s investigations isn’t really an instrument, but a radio on the spacecraft that will send out signals to be tracked by project scientists.
By following the signal produced by the radio sitting on the rotating planet, Banerdt and his colleagues can watch Mars rotate on its axis and actually watch that axis “wobble a little bit”.
The size of Mars’ wobble will help scientists determine the distribution of material inside the planet and get a better understanding of the size and density of the planet’s core and determine whether it’s solid or liquid.
The InSight lander will also have a weather station and camera that will provide further information about Mars.
The new Mars lander’s mission is expected to last for about one Mars-year or two Earth years.
By better understanding what’s behind the interior of Mars, Banerdt said that scientists will be able to get a better idea of what the Earth might have looked like very early in its history.