NASA InSight Lander: Mars Mission Will Probe "Origin of the Planets"

While tech geeks go nuts on Cyber Monday this year, NASA’s InSight Lander will be making its historic touchdown on Mars. It’s expected to land at Elysium Planitia, an equatorial plane, on November 26, marking the first day of a Martian-year-long mission — that’s 687 days — to investigate the heart of the red planet. On Wednesday, NASA briefed the public on what exactly InSight will be doing during its stay.

The lander launched on May 5 from Vandenberg Air Force Base, but the end of its 301 million-mile journey is just the beginning of its real test, which starts with an atmospheric entry. As InSight enters the Martian atmosphere, clad in its heat shields, it will be going over 12,000 miles per hour, says Tom Hoffman, the InSight project manager. With the aid of a parachute, the lander will slow down as it falls, and retro-rockets further slow it to five miles per hour by the time it hits the surface. Then InSight will deploy its solar panels, which is when the fun really begins.

“Since we’re the very first lander on Mars to last for an entire Martian year — so 26 Earth months — not moving and just using solar power, it’s important to get those solar arrays out,” said Hoffman.

The lander has some special instruments aboard, so even though it can’t get around, it will still be the first Martian lander to dig deep below the surface of the planet in some key ways.

InSight Will Measure Seismic Activity on Mars

The SEIS instrument will allow InSight to probe the planet’s geological properties. The Seismic Experiment for Interior Structure consists of a small, domed device that will sit on the surface of Mars and collect information about Marsquakes. While Mars doesn’t have tectonic plate movement like Earth does, it may have seismic activity caused by magma or other geothermal phenomena. During its operational life, the SEIS instrument, with its six seismometers, will record the full spectrum of seismic waves, as well as the direction they’re traveling.

Bruce Banerdt, Ph.D., the InSight principal investigator, explained that collecting data on the seismic waves will help researchers untangle the mysteries of Mars’ interior construction.

“When we measure those amplitudes, measure those vibrations at the surface, we have techniques that we can use to sort of unravel the entire pathway through the planet and figure out what kind of materials that they pass through, what kind of interfaces that they may have bounced off of, and then we can use that information to understand the size, the composition, and the configuration of all the layers of the inside of the planet, particularly the core, the mantle, and the crust,” he said. “These parameters, these divisions and compositions, are all very closely tied to how that planet formed early on.”

In addition to the seismic activity on Mars, InSight will delve into the properties of the planet’s crust.

HP3 Will Collect Data on the Thermal Properties of Mars

The Heat Flow and Physical Properties Probe — HP3 for short — will let the stationary InSight lander reach beyond its immediate vicinity and investigate the properties of the rock and soil far below the surface. Using a spring-loaded internal hammer, explained Sue Smrekar, Ph.D., the InSight deputy principal investigator, the HP3 probe will pound itself deep down below the surface.

“We don’t have the benefit of the astronaut to drill a hole for us,” she said, “so the HP-cubed actually has to hammer itself into the ground.”

This probe, affectionately nicknamed “the mole,” will send out a pulse of heat and then detect how long the surrounding soil takes to cool off. This will tell scientists whether the Martian soil is conducting heat or insulating.

“We’re going to Mars specifically to look back into the origin of the planets of the solar system,” said Banerdt. “If you really want to know about the very beginning of the planets, sort of the birth of the planets, what happens to them just in the few first tens of millions of years after their formation, Earth is not a very good laboratory.”

This is because, with its constant volcanic activity and plate tectonics, much of the early evidence of Earth’s formation has been shifted or altered over billions of years. Mars, on the other hand, is large enough to show some of the geological signatures of planetary formation, but since it’s quite seismically inactive, it makes a great place for scientists to investigate the evidence from its early formation.