26 November 2018
At the end of the critical approximately seven-minute landing process InSightis slowed down by autonomously controlled descent engines and lands on Mars.
Flight over the InSight landing site in Elysium Planitia
On 26 November 2018, the NASA InSight probe landed on Elysium Planitia on Mars at 4.5 degrees north and 135.9 degrees east. This video shows an overflight over the landing site and its surroundings. The video was based on a digital terrain model generated with stereo image data acquired by DLR's High Resolution Stereo Camera (HRSC) of the DLR.
DLR (CC-BY 3.0).
After the cruise stage is jettisoned, the landing probe will enter the Martian atmosphere at 20:47 CET at a speed of 3600 kilometres per hour. An intervention in the landing process is not possible: Since it takes a signal from Earth to reach Mars 8 minutes and 6 seconds, the landing will have already taken place by the time the last signal from InSight before entering the atmosphere reaches Earth. The probe will reach the surface seven minutes after atmospheric entry. About half a minute after entering the atmosphere, the friction of the gas molecules of the high atmosphere will cause the heat shield to begin to glow at the tip at a temperature of about 1500 degrees Celsius and then cool again. Peak deceleration will happen about 2 minutes after atmospheric entry 15 seconds later, at up to 7.5 g. Before the parachute is deployed, friction between the atmosphere and the heat shield will remove nearly 99.5 percent of the entry vehicle’s kinetic energy.
The InSight brake parachute opens at the supersonic speed of 1500 kilometres per hour. The initial load on deployment at an altitude of 12 kilometres is 55,600 Newton. Barely three minutes later, 1200 metres above the landing site, the probe will separate from the parachute and use its descent engines to decelerate until landing at around 20:53 CET. The picture shows the supersonic parachute at Lockheed-Martin in Denver, Colorado during a test.
InSight's solar panels are deployed and the probe is tested in its deployment configuration during a test in the clean room. In the middle of the platform, the protective cover of the seismometer SEIS, to the right of which is the heat flux probe HP3 developed at DLR.
DLR has contributed the HP3 experiment to the NASA InSight mission. HP3 stands for ‘Heat Flow and Physical Properties Package’ and the instrument was developed under the leadership of the DLR Institute of Planetary Research. The thermal conductivity of the material below the landing site and the heat flow from the interior of Mars to the surface will be measured using a penetrometer hammered five metres deep into the Martian regolith. The experiment is designed for an operational life of two Earth years. Essential components of HP3 are the ‘Mole’ and the ribbon cable with the temperature sensors, which the Mole will pull behind it into the ground to perform measurements.
Just a few weeks from now, the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) HP3 Mole will start hammering its way automatically into the subsoil of the Red Planet to measure its inner heat. "By participating in the InSight mission, Germany is making a major contribution to expanding our knowledge of the Red Planet," emphasises Pascale Ehrenfreund, Chair of the DLR Executive Board. "The HP3 experiment is an innovation in the exploration of our neighbouring planet – both scientifically and technologically. It is a view beyond the next horizon." The HP3 experiment landed on Mars with NASA's InSight space probe on 26 November 2018 at 20:52:59 Central European Time. The geophysical observatory travelled almost 500 million kilometres before settling gently on the Elysium Planitia plains just north of the Martian equator. "We are delighted that a DLR experiment is now present on Mars for the first time and that we can make a significant contribution to this hitherto unparalleled exploration of the Red Planet's interior, which is certain to go down in aerospace history," says Hansjörg Dittus, DLR Executive Board Member for Space Research and Technology after observing the landing from Pasadena, California.
Thomas Jarzombek, German Federal Government Coordinator for Aerospace, is also extremely pleased: "I congratulate the project managers on the successful landing on Mars. The InSight mission demonstrates the achievements of international cooperation in space research. Germany has made a key contribution to the HP3 experiment, which is proof of DLR's outstanding and internationally recognised expertise. In addition, Germany is providing additional contributions to the mission as part of the National Programme for Space and Innovation of the German Federal Ministry for Economic Affairs and Energy. All in all, this is proof of the German Government's successful support to science and technology."
The InSight mission was launched from Vandenberg in California on 5 May 2018. Hurtling into the Martian atmosphere at a speed of 19,800 kilometres per hour, it was slowed down to a landing velocity of just eight kilometres per hour in less than seven minutes. Its three legs finally came to rest on Martian soil at 20:52:59 CET. "We are very excited about the upcoming analysis of the landing craft's environment. Once that it complete, we will select the ideal place to position the instruments with our US colleagues", says Tilman Spohn, Principal Investigator of the HP3 experiment from the DLR Institute of Planetary Research in Berlin. "Our research will begin then."
A robot arm will place the Martian 'Mole' in January
Once InSight has delivered the first images of the area around the landing site, the next step will be to produce a 3D model of the surface. Researchers will then use this model to decide where – within a radius of one-and-a-half metres – the robot arm should deposit the Mars mole HP3. This will take place in early January. Release of the Mars seismometer SEIS (Seismic Experiment for Interior Structure) is already scheduled for December. DLR is also involved in this experiment, which was built by an international consortium led by the French space agency CNES.
"An ideal location for our Mars mole would be one that is as sandy as possible and does not contain any rocks," says HP3 operations manager Christian Krause from the DLR Microgravity User Support Center (MUSC), who will teleoperate the Mole together with his colleagues, initially in the control room at the Jet Propulsion Laboratory (JPL) in California and later at the control centre in Cologne. The Mole will burrow its way in small increments to a depth of up to five metres, dragging a tether equipped with highly accurate temperature sensors. The Mole will take a break every 50 centimetres to measure the thermal conductivity of the Martian soil. In total, the temperature sensors should deliver data on the temperature gradient in the subsoil for two years. Scientists will then use this data and the thermal conductivity to calculate how much heat the interior of Mars is still emitting today. "Our plan is to use these measurements to determine the temperature of Mars' interior and to characterise the current geological activity beneath its crust," explains Spohn. "In addition, we want to find out how the interior of Mars developed, whether it still possesses a hot molten core and what makes Earth so special by comparison." At present, researchers only have imprecise knowledge of how Mars is structured into a core, mantle and crust, their individual properties and why the dynamism of its inner development diminished so quickly compared to Earth.
The HP3 experiment on the NASA InSight mission
The InSight mission is being conducted by the Jet Propulsion Laboratory (JPL) in Pasadena, California, on behalf of NASA's Science Mission Directorate. InSight is a mission in the NASA Discovery Program. DLR is contributing the HP3 experiment to the mission. Scientific leadership lies with the DLR Institute of Planetary Research, which was also in charge of developing the experiment in collaboration with the DLR institutes of Space Systems, Optical Sensor Systems, Space Operations and Astronaut Training, Composite Structures and Adaptive Systems, System Dynamics and Control, as well as the Institute of Robotics and Mechatronics. Industrial partners are Astronika and the CBK Space Research Centre, Magson GmbH and Sonaca SA. The scientific partners are the ÖAW Space Research Institute in the Austrian Academy of Sciences and the University of Kaiserslautern. The DLR Microgravity User Support Center (MUSC) in Cologne is responsible for HP3 operations.
In addition, the DLR Space Administration, with funding from the Federal Ministry for Economic Affairs and Energy, supported a contribution of the Max Planck Institute for Solar System Research to the French main instrument.
Detailed information on InSight and the HP3 experiment are available on DLR's dedicated mission site: www.dlr.de/en/insight. For mission updates follow @NASAInSight on Twitter.
Last modified:27/11/2018 09:15:35