NASA evaluates four candidate sites for 2016 Mars mission

September 4, 2013
The process of selecting a site for NASA's next landing on Mars, planned for September 2016, has narrowed to four semifinalist sites located close together in the Elysium Planitia region of Mars. The mission known by the acronym InSight will study the Red Planet's interior, rather than surface features, to advance understanding of the processes that formed and shaped the rocky planets of the inner solar system, including Earth. Credit: NASA/JPL-Caltech

( —NASA has narrowed to four the number of potential landing sites for the agency's next mission to the surface of Mars, a 2016 lander to study the planet's interior.

The stationary Interior Exploration Using Seismic Investigations, Geodesy and Heat Transport (InSight) is scheduled to launch in March 2016 and land on Mars six months later. It will touch down at one of four sites selected in August from a field of 22 candidates. All four semi-finalist spots lie near each other on an equatorial plain in an area of Mars called Elysium Planitia.

"We picked four sites that look safest," said geologist Matt Golombek of NASA's Jet Propulsion Laboratory in Pasadena, Calif. Golombek is leading the site-selection process for InSight. "They have mostly smooth terrain, few rocks and very little slope."

Scientists will focus two of NASA's Mars Reconnaissance Orbiter cameras on the semi-finalists in the coming months to gain data they will use to select the best of the four sites well before InSight is launched.

The mission will investigate processes that formed and shaped Mars and will help scientists better understand the evolution of our 's , including Earth. Unlike previous Mars landings, what is on the surface in the area matters little in the choice of a site except for safety considerations.

"This mission's science goals are not related to any specific location on Mars because we're studying the planet as a whole, down to its core," said Bruce Banerdt, InSight principal investigator at JPL. "Mission safety and survival are what drive our criteria for a landing site."

This artist's concept depicts the stationary NASA Mars lander known by the acronym InSight at work studying the interior of Mars. Credit: JPL/NASA

Each semifinalist site is an ellipse measuring 81 miles (130 kilometers) from east to west and 17 miles (27 kilometers) from north to south. Engineers calculate the spacecraft will have a 99-percent chance of landing within that , if targeted for the center.

Elysium is one of three areas on Mars that meet two basic engineering constraints for InSight. One requirement is being close enough to the equator for the lander's solar array to have adequate power at all times of the year. Also, the elevation must be low enough to have sufficient atmosphere above the site for a safe landing. The spacecraft will use the atmosphere for deceleration during descent.

All four semifinalist sites, as well as the rest of the 22 candidate sites studied, are in Elysium Planitia. The only other two areas of Mars meeting the requirements of being near the equator at low elevation, Isidis Planitia and Valles Marineris, are too rocky and windy. Valles Marineris also lacks any swath of flat ground large enough for a safe landing.

InSight also needs penetrable ground, so it can deploy a heat-flow probe that will hammer itself 3 yards to 5 yards into the surface to monitor heat coming from the planet's interior. This tool can penetrate through broken-up surface material or soil, but could be foiled by solid bedrock or large rocks.

"For this mission, we needed to look below the surface to evaluate candidate landing sites," Golombek said.

InSight's heat probe must penetrate the ground to the needed depth, so scientists studied Mars Reconnaissance Orbiter images of large rocks near Martian craters formed by asteroid impacts. Impacts excavate rocks from the subsurface, so by looking in the area surrounding craters, the scientists could tell if the subsurface would have probe-blocking rocks lurking beneath the soil surface.

InSight also will deploy a seismometer on the surface and will use its radio for scientific measurements.

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1 / 5 (1) Sep 05, 2013
"3 yards to 5 yards"
No, not again.
"3 yards = 3 meters ??" he, he

Remember "NASA's Mars Climate Orbiter" ;)
"The software calculated the force the thrusters needed to exert in pounds of force. A separate piece of software took in the data assuming it was in the metric unit: newtons"
not rated yet Sep 05, 2013
Why are we sending yet another lander to Mars doing rather uninteresting stuff when there's much more interesting targets in the solar system just begging to be explored? (Ganymed, IO, Europa, Titan...and Ceres is also shaping up to be a hot candidate for interesting studies).

5 / 5 (1) Sep 05, 2013
Why are we sending yet another lander to Mars doing rather uninteresting stuff when there's much more interesting targets in the solar system just begging to be explored?

This is really a small mission compared to any of the ones you listed. The bulk of InSight is recycled Phoenix lander hardware, so it's not a big, high dollar, high risk mission.

This is probably also important if we hope to understand the exoplanets we're finding.

We will eventually want to do this on all the major bodies of the solar system with solid surfaces, I would guess. That would allow us to compare and contrast them.

Since we obviously won't be visiting any exoplanets in our lifetimes, if we hope to understand any of the ones we're discovering, then comparing the exoplanets to the bodies here in our solar system might be our only chance to know anything about them. That sounds like a worthy goal to me.
not rated yet Sep 05, 2013
We are doing this precisely because it _isn't_ uninteresting, according to the planetary science program that the scientists has agreed on. Also, going to Mars gets much faster turnaround on the science, so we learn faster.

Knowing if Mars is still active or when it shut down its core is key to open up habitability projections over volumes and times of the subsurface locales. Getting to know another planets core for the first time is even extra interesting re Earth.

We can argue for why we want to go to the other places too, but we should do it from a position of knowledge of what is prioritized and why. Else what is discussed will become a strawman ("rather uninteresting stuff").
not rated yet Sep 06, 2013
I'm not arguing that it's worthless. I'm saying there are much more interesting targets to explore. Also, even if we stick to Mars, there are a lot more interesting things to look for there than geological activity.

We should dig to look for water. We should dig to look for signs of (past) life. We should DIG to see iif we can - because that is the real test of whether we'll ever be able to set up research outpost or not.
We should send a friggin' microscope to Mars (if not an AFM or at the very least an EM. Both of which can be built compact enough to fit on a lander)..instead of these 'panorama-shot' bots.

They are cool - no doubt. But somehow NASA must start capturing the imagination of the people again. And photos of deserts just don't do that anymore.
1 / 5 (1) Sep 07, 2013
"They have mostly smooth terrain, few rocks and very little slope."
That sounds like tundra. Very boring, and a waste of resources. It really does matter where you land on Mars, if you want to find truly interesting things, and, that being said, we should therefore not be powering the Mars rovers with sunlight, but rather with a nuclear power source. They should be made tough enough to withstand weather extremes and mobile enough to navigate through rough and hilly terrain. The Insight project is a good example of where saving money just costs money.

Unless they're looking for oil. Then, maybe, they're in the right place. Don't laugh.
1 / 5 (1) Sep 07, 2013
For all the hype about Curiosity, there hasn't been much mention of it in the news lately, nor even on this site. It seems to have just dropped off the radar.

At least Spirit and Opportunity were mentioned quite often.

Perhaps the issue is that Curiosity hasn't found one thing to justify it's insane expense.

With nothing worthy to talk about, NASA just sort of sits in the corner quietly and hopes nobody notices.

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