“We’re in the instrument deployment phase,” says Matt Golombek of the Jet Propulsion Laboratory in Pasadena, California.
The robotic probe is slogging through its paces near the Martian equator at Elysium Planitia—smooth, sandy, and bleak. There, nights are typically 100 below zero Fahrenheit.
A volleyball-size sphere now shelters InSight’s seismometer from wind, cold, and wild temperature fluctuations. Inside that casing, SEIS is “fully operational,” says NASA—and able to discern “surface movements smaller than a hydrogen atom.”
Or detect a Marsquake “on the other side of the planet,” says Bruce Banerdt, InSight’s principal investigator. He expects SEIS to spot dozens of them during the two-year mission.
Before the shield went on, the seismometer was already running, even collecting data while bolted to the lander. No quakes so far, but dust devils abound, apparently; SEIS has already identified “probably a half-dozen,” says Golombek.
What’s next: InSight’s motorized arm will put the heat flow probe—with its mechanical mole—on the ground. One meter away from the seismometer (just over three feet) is about right, Golombek says. Any closer, and interference from either instrument could degrade the data.
The mole—self-hammering—will then pull the probe deep inside Mars.
That hammering likely begins late February. Three to five meters down (about 10 to 16 feet) is the goal. But the mole plods. “It will probably take more than a month to hammer down to the desired depth,” Golombek says.
Temperature sensors attached to the probe will measure the heat escaping the Martian interior. Comprehend a planet’s “heat engine,” says Banerdt, and scientists may discover how its “geological processes” happened—how mountains, valleys, lakes, and rivers formed. Clues to how life kickstarted on Earth will emerge.
That evidence is erased from Earth, a place so geologically lively that its early history is obliterated. But Mars remains much the way it was billions of years ago.
One thing may be in the way: a big rock.
The mole can push aside small ones, anything less than four inches across. Larger objects are tricky; conceivably, the mole might wriggle past a sizeable rock resting at a sharp angle.
But hit a flat one, straight on—and the mole is done. “It can’t go directly through hard, intact rock,” says Golombek.
Nor can the mole back up and try again: “One time in, and that’s it.”
Golombek suspects few rocks await below.
“We’ve done a thousand calculations,” he says. “We looked at the surface as best we could. There’s a fairly high probability of success.”
Nobody knows the odds better than Golombek, a planetary geologist and InSight’s landing site lead. For the past quarter century, he has worked “just Mars”—including the Spirit, Opportunity, and Curiosity rover missions.
“I often call myself the oldest Martian,” he says.
Yet even Golombek’s not exactly sure what might happen to the mole.
“This activity,” he sighs, “is not for the faint of heart.”
“On A Mission”—the new podcast series on InSight’s journey to Mars, presented by NASA’s Jet Propulsion Laboratory—is here.