Credit: NASA/JPL-Caltech

Credit: NASA/JPL-Caltech

Credit: NASA/JPL-Caltech

Credit: NASA/JPL-Caltech

Credit: DLR/Screengrab/Inside Outer Space


Components of the HP3 heat flow probe. Top left: the radiometer (RAD), which is used to measure the radiation temperature (roughly equivalent to the ground temperature) of the surface. Right: the casing with the mole penetrometer, the temperature measuring cable (TEM-P) and the data cable (ET) connected to the lander. In addition, the casing contains an optical length meter for determining the length of the temperature measuring cable that has been pulled from the casing. The mole contains the TEM-A active thermal conductivity sensor and the STATIL tiltmeter. Bottom left: the electronic control unit, known as the back end electronics (BEE), which remains on the lander and is connected to the probe via the ET.
Credit: DLR


InSight has deployed its domed Wind and Thermal Shield (WTS), setting it atop the French-supplied SEIS, short for Seismic Experiment for Interior Structure – a seismometer.

The WTS has a tripod and a protective skirt that tightly ‘hugs’ the ground around the seismometer to stop wind blowing and influence measurements.

Next up…and down!

The next major milestone for the Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) mission is deploying the German Heat Flow and Physical Properties Package (HP3).

It too, like the seismometer and Wind and Thermal Shield, will be placed on the surface of Mars by InSight’s robotic arm. HP3 is designed to burrow down beneath the Red Planet’s topside — with its tether embedded with heat sensors — to a depth of 16 feet (five meters). If successful, the HP3 will plow deeper than any previous arms, scoops, drills or probes before it.

On the surface

According to Tilman Spohn, HP3’s principal investigator at the German Aerospace Center’s Institute of Planetary Research in Berlin, Germany:

“We expect to be on the surface of Mars on February 13th and start operations about a week later,” Spohn told Inside Outer Space. “However, be aware that these dates are still not cast in concrete yet.”

Mole action plan

HP3 can take Mars’ temperature to reveal how much heat is still flowing out of the interior of the planet. Weighing a little over 6.5 pounds (about 3 kilograms) HP3’s “Mole” hammers itself under the surface. A maximum of 2 watts of power is available while burrowing underneath the surface.

The German Aerospace Center’s (DLR) HP3 heat flow probe has the Mole pulling a ribbon cable equipped with 14 temperature sensors behind it. Once the probe has reached its target depth, the temperature will be measured by all of the sensors every 15 minutes for several months.




























For an informative DLR video detailing how the Heat Flow and Physical Properties Package (HP3) works, go to:

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