ExoMars (rover)

ExoMars rover

ExoMars rover prototype, displayed at the 2009 U.K. Royal Astronomical Society National Annual Meeting
Mission type	Mars rover
Operator	ESA · RKA
Website	exploration.esa.int/mars/48088-mission-overview/
Mission duration	≥ 6 months
Spacecraft properties
Manufacturer	Astrium · Airbus
Launch mass	310 kg (680 lb)
Power	1,200 W solar array/1142 W·h Lithium-ion[1]
Start of mission
Launch date	July 2020[2]
Rocket	Proton rocket
Mars rover
ExoMars programme ← Trace Gas Orbiter and Schiaparelli lander

The ExoMars rover is a planned robotic Mars rover, part of the international ExoMars programme led by the European Space Agency and the Russian Roscosmos State Corporation.^[3][4]

The plan calls for a Russian launch vehicle, an ESA carrier module and a Russian lander that will deploy the rover to Mars' surface,^[5] scheduled to launch in July 2020.^[2] Once safely landed, the solar powered rover would begin a six-month (218-sol) mission to search for the existence of past or present life on Mars. The ExoMars Trace Gas Orbiter, launched in 2016, will operate as the rover's data-relay satellite.^[6]

History

The rover is an autonomous six-wheeled terrain vehicle once designed to weigh up to 295 kg (650 lb), approximately 60% more than NASA's 2004 Mars Exploration Rovers Spirit and Opportunity,^[7] but about one third that of NASA's Curiosity rover launched in 2011.

In February 2012, following NASA's withdrawal, the ESA went back to previous designs for a smaller rover,^[8] once calculated to be 207 kg (456 lb). Instrumentation will consist of the exobiology laboratory suite, known as "Pasteur analytical laboratory" to look for signs of biomolecules or biosignatures from past or present life.^{[9][10][11][12]} Among other instruments, the rover will also carry a 2-metre (6 ft 7 in) sub-surface drill to pull up samples for its on-board laboratory.^[13]

The lead builder of the ExoMars rover, the British division of Airbus Defence and Space, began procuring critical components in March 2014.^[14] In December 2014, ESA member states approved the funding for the rover, to be sent on the second launch in 2018,^[15] but insufficient funds had already started to threaten a launch delay until 2020.^[16] The wheels and suspension system are paid by the Canadian Space Agency and are being manufactured by MDA Corporation in Canada.^[14]

As of March 2013, the spacecraft was scheduled to launch in 2018 with a Mars landing in early 2019.^[5] Delays in European and Russian industrial activities and deliveries of scientific payloads, however, forced the launch to be pushed back. In May 2016, ESA announced that the mission had been moved to the next available launch window of July 2020.^[2] However, an ESA ministerial meeting in December 2016 will consider mission issues including €300 million in ExoMars funding and lessons learned from the ExoMars 2016 mission.^[17] One concern is that the Schiaparelli module crashed during its Mars atmospheric entry, and this landing system is being produced in near duplication for the ExoMars 2020 lander.^[17]

Navigation

An early design ExoMars rover test model at the ILA 2006 in Berlin

Another early test model of the rover from the Paris Air Show 2007

The ExoMars mission requires the rover to be capable of driving 70 m (230 ft) across the Martian terrain per sol to enable it to meet its science objectives.^[18][19] The rover is designed to operate at least seven months and drive 4 km (2.5 mi), after landing.^[14]

Since the rover communicates with the ground controllers via the ExoMars Trace Gas Orbiter, and the orbiter only passes over the rover approximately twice per sol, the ground controllers will not be able to actively guide the rover across the surface. The ExoMars Rover is therefore designed to navigate autonomously across the Martian surface.^[20][21] A pair of stereo cameras allow the rover to build up a 3D map of the terrain,^[22] which the navigation software then uses to assess the terrain around the rover so that it avoids obstacles and finds an efficient route to the ground controller specified destination.

On 27 March 2014, a "Mars Yard" was opened at Airbus Defence and Space in Stevenage, UK, to facilitate the development and testing of the rover's autonomous navigation system. The yard is 30 by 13 m (98 by 43 ft) and contains 300 tonnes (330 short tons; 300 long tons) of sand and rocks designed to mimic the terrain of the Martian environment.^[23][24]

Payload

ExoMars prototype rover, 2009

ExoMars rover design, 2010

Rover prototype being tested near the Paranal Observatory, 2013

Rover prototype at the 2015 Cambridge Science Festival

The scientific payload is as follows:^[3]

Imaging system

Panoramic Camera System (PanCam)

The PanCam has been designed to perform digital terrain mapping for the rover and to search for morphological signatures of past biological activity preserved on the texture of surface rocks. The PanCam assembly includes two wide angle cameras for multi-spectral stereoscopic panoramic imaging, and a high resolution camera for high-resolution colour imaging.^[25][26] The PanCam will also support the scientific measurements of other instruments by taking high-resolution images of locations that are difficult to access, such as craters or rock walls, and by supporting the selection of the best sites to carry out exobiology studies. Stained glass will be used to prevent ultraviolet radiation from changing image colors. This will allow for true color images of the surface of Mars.^[27]

Core drill

The present environment on Mars is exceedingly hostile for the widespread proliferation of surface life: it is too cold and dry and receives large doses of solar UV radiation as well as cosmic radiation. Notwithstanding these hazards, basic microorganisms or their ancient remains may be found in protected places underground or within rock cracks and inclusions.^[28] The ExoMars core drill is designed to acquire soil samples down to a maximum depth of 2 metres (6 ft 7 in) in a variety of soil types. The drill will acquire a core sample 1 cm (0.4 in) in diameter by 3 cm (1.2 in) in length, extract it and deliver it to the inlet port of the Rover Payload Module, where the sample will be distributed, processed and analyzed. The ExoMars drill embeds the Mars Multispectral Imager for Subsurface Studies (Ma-Miss) which is a miniaturised infrared spectrometer devoted to the borehole exploration. The system will complete experiment cycles and at least two vertical surveys down to 2 metres (with four sample acquisitions each). This means that a minimum number of 17 samples shall be acquired and delivered by the drill for subsequent analysis.^[29][30]

Scientific instruments

The science package in the ExoMars rover will hold a variety of instruments collectively called Pasteur suite;^[10] these instruments will study the environment for habitability, and possible past or present biosignatures on Mars. These instruments are placed internally and used to study collected samples:^[31][32]

Pasteur instrument suite

• Mars Organic Molecule Analyzer (MOMA) is the rover's largest instrument. It will conduct a broad-range, very-high sensitivity search for organic molecules in the collected sample. It includes two different ways for extracting organics: laser desorption and thermal volatilisation, followed by separation using four GC-MS columns. The identification of the evolved organic molecules is performed with an ion trap mass spectrometer.^[3] MOMA is being developed in partnership with NASA.^[33] The Max Planck Institute for Solar System Research is leading the development. The mass spectrometer is provided from the Goddard Space Flight Center, while the GC is provided by the two French institutes LISA and LATMOS. The UV-Laser is being developed by the Laser Zentrum Hannover.
• Infrared imaging spectrometer (MicrOmega-IR) is an infrared imaging spectrometer that can analyse the powder material derived from crushing samples collected by the drill.^[3] Its objective is to study mineral grain assemblages in detail to try to unravel their geological origin, structure, and composition. These data will be vital for interpreting past and present geological processes and environments on Mars. Because MicrOmega-IR is an imaging instrument, it can also be used to identify grains that are particularly interesting, and assign them as targets for Raman and MOMA-LDMS observations.
• Raman spectrometer (Raman) will provide geological and mineralogical context information complementary to that obtained by MicrOmega-IR. It is a very useful technique employed to identify mineral phases produced by water-related processes.^[34][35][36] It will help to identify organic compounds and search for life by identifying the mineral products and indicators of biologic activities (biosignatures).

External

• Ground-penetrating radar, called WISDOM (for Water Ice and Subsurface Deposit Information On Mars) will explore the subsurface of Mars to identify layering and help select interesting buried formations from which to collect samples for analysis.^[37] It can transmit and receive signals using two, small Vivaldi-antennas mounted on the aft section of the rover. Electromagnetic waves penetrating into the ground are reflected at places where there is a sudden transition in the electrical parameters of the soil. By studying these reflections it is possible to construct a stratigraphic map of the subsurface and identify underground targets down to 2 to 3 m (7 to 10 ft) in depth, comparable to the 2 m reach of the rover's drill. These data, combined with those produced by the PanCam and by the analyses carried out on previously collected samples, will be used to support drilling activities.^[38]
• Mars Multispectral Imager for Subsurface Studies (Ma-MISS) is an infrared spectrometer located inside the core drill. Ma-MISS will observe the lateral wall of the borehole created by the drill to study the subsurface startigraphy, to understand the distribution and state of water-related minerals, and to characterize the geophysical environment. The analyses of unexposed material by Ma-MISS, together with data obtained with the spectrometers located inside the rover, will be crucial for the unambiguous interpretation of the original conditions of Martian rock formation.^[3][39] The composition of the regolith and crustal rocks provides important information about the geologic evolution of the near-surface crust, the evolution of the atmosphere and climate, and the existence of past or present life.
• Close-Up Imager (CLUPI), to visually study rock targets at close range (50 cm/20 in) with sub-millimetre resolution. This instrument will also investigate the fines produced during drilling operations, and image samples collected by the drill. The close-up imager has variable focusing and can obtain high-resolution images at longer distances.^[3][32]

Russian instruments

• The Infrared Spectrometer for ExoMars (ISEM),^[32][40] will be installed on the rover's beam. It will be used to assess bulk mineralogy characterization and remote identification of water-related minerals. Working with PanCam, ISEM will contribute to the selection of suitable samples for further analysis by the other instruments.
• ADRON-RM is a neutron spectrometer to determine the amount of subsurface hydration, and the possible presence of water ice.^[32][40][41] Adron will be used in combination with WISDOM to study the subsurface beneath the rover and to search for suitable areas for drilling and sample collection.
• Fourier spectrometer, mounted on the rover's mast will acquire temperature and aerosol measurements.^[41]
• Roscosmos will also provide radioisotope heater units (RHU) for the rover.^[3]

De-scoped instruments

Urey design, 2013

The proposed payload has changed several times. The last major change was after the program switched from the larger rover concept back to the previous 300 kg (660 lb) rover design in 2012.^[32]

• Mars X-Ray Diffractometer (Mars-XRD) - Powder diffraction of X-rays would give exact composition of the crystalline minerals.^[42][43] This instrument includes also an X-ray fluorescence capability that can provide useful atomic composition information.^[44] The identification of concentrations of carbonates, sulphides or other aqueous minerals may be indicative of a Martian [hydrothermal] system capable of preserving traces of life. In other words, it would examine the past Martian environmental conditions, and more specifically the identification of conditions related to life.^[32]
• The Urey instrument was planned to search for organic compounds in Martian rocks and soils as evidence for past or present life and/or prebiotic chemistry. Starting with a hot water extraction, only soluble compounds are left for further analysis. Sublimation, and capillary electrophoresis makes it possible to identify amino acids. The detection would be by laser-induced fluorescence, a highly sensitive technique, capable of parts-per-trillion sensitivity. These measurements would be made at a thousand times greater sensitivity than the Viking GCMS experiment, and would significantly advance our understanding of the organic chemistry of Martian soils.^[32][45][46]
• Miniaturised Mössbauer Spectrometer (MIMOS-II) provides the mineralogical composition of iron-bearing surface rocks, sediments and soils. Their identification would aid in understanding water and climate evolution and search for biomediated iron-sulfides and magnetites, which could provide evidence for former life on Mars.
• The Life Marker Chip was for some time part of the planned payload. This instrument was intended to use a surfactant solution to extract organic matter from samples of martian rock and soil, then detect the presence of specific organic compounds using an antibody-based assay.^[47][48][49]

Landing site selection

Location of Oxia Planum

Geological morphology of Oxia Planum, chosen for its potential to preserve biosignatures and its smooth surface

After a review by an ESA-appointed panel, a short list of four sites was formally recommended in October 2014 for further detailed analysis:^[50][51]

• Mawrth Vallis
• Oxia Planum
• Hypanis Vallis
• Aram Dorsum

On 21 October 2015, Oxia Planum was chosen as the preferred landing site for the ExoMars rover assuming a 2018 launch. Since the launch was delayed to 2020, Aram Dorsum and Mawrth Vallis are also be considered.^[52][53]

After the ExoMars 2020 surface platform lands, it will deploy ramps to deliver the ExoMars rover to the surface. The platform will remain stationary and will start a one-year mission to investigate the surface environment at the landing site.^[54]

See also

• Astrobiology
• List of missions to Mars

References

1. "Saft Li-ion Battery to Power the ExoMars Rover as it Searches for Life on the Red Planet". Saft Batteries (Press release). Business Wire. 8 July 2015. Retrieved 8 July 2015.
2. "Second ExoMars mission moves to next launch opportunity in 2020" (Press release). European Space Agency. 2 May 2016. Retrieved 2 May 2016.
3. Vago, Jorge; Witasse, Olivier; Baglioni, Pietro; Haldemann, Albert; Gianfiglio, Giacinto; et al. (August 2013). "ExoMars: ESA's Next Step in Mars Exploration" (PDF). Bulletin. European Space Agency (155): 12–23.
4. Katz, Gregory (27 March 2014). "2018 mission: Mars rover prototype unveiled in UK". Excite.com. Associated Press. Retrieved 29 March 2014.
5. "Russia and Europe Team Up for Mars Missions". Space.com. 14 March 2013. Retrieved 24 January 2016.
6. de Selding, Peter B. (26 September 2012). "U.S., Europe Won't Go It Alone in Mars Exploration". Space News. Retrieved 5 January 2014.
7. Vego, J. L.; et al. (2009). ExoMars Status (PDF). 20th Mars Exploration Program Analysis Group Meeting. 3–4 March 2009. Arlington, Virginia. European Space Agency. Retrieved 15 November 2009.
8. "NASA Jumping Out of Joint ESA Mars Mission". RedOrbit.com. 7 February 2012. Retrieved 15 February 2012.
9. "Press Info: ExoMars Status" (Press release). Thales Group. 8 May 2012. Retrieved 8 May 2012.
10. "The ExoMars Instruments". European Space Agency. 1 February 2008. Archived from the original on 26 October 2012. Retrieved 8 May 2012.
11. Amos, Jonathan (15 March 2012). "Europe still keen on Mars missions". BBC News. Retrieved 16 March 2012.
12. "Rover surface operations". European Space Agency. 18 December 2012. Retrieved 16 March 2012.
13. Kish, Adrienne (31 August 2009). "Amase-ing Life On The Ice". Astrobiology Magazine. Archived from the original on 5 September 2009.
14. Clark, Stephen (3 March 2014). "Facing funding gap, ExoMars rover is on schedule for now". Spaceflight Now. Retrieved 3 March 2014.
15. "Europe Agrees to Fund Ariane 6 Orbital Launcher". ABC News. Berlin, Germany. Associated Press. 2 December 2014. Retrieved 2 December 2014. ESA's member states also approved funding to upgrade the smaller Vega launch vehicle, continue participating in the International Space Station, and proceed with the second part of its ExoMars mission.
16. "Money Troubles May Delay Europe-Russia Mars Mission". Industry Week. Agence France-Presse. 15 January 2016. Retrieved 16 January 2016.
17. Clery, Daniel (25 October 2016). "Mars lander crash complicates follow-up rover in 2020". Science. doi:10.1126/science.aal0303. Retrieved 4 November 2016.
18. Lancaster, R.; Silva, N.; Davies, A.; Clemmet, J. (2011). ExoMars Rover GNC Design and Development. 8th Int'l ESA Conference on Guidance & Navigation Control Systems. 5–10 June 2011. Carlsbad, Czech Republic.
19. Silva, Nuno; Lancaster, Richard; Clemmet, Jim (2013). ExoMars Rover Vehicle Mobility Functional Architecture and Key Design Drivers (PDF). 12th Symposium on Advanced Space Technologies in Robotics and Automation. 15–17 May 2013. Noordwijk, the Netherlands. European Space Agency.
20. Amos, Jonathan (5 September 2011). "Smart UK navigation system for Mars rover". BBC News.
21. "Mars rover Bruno goes it alone". EADS Astrium. 14 September 2011.
22. McManamon, Kevin; Lancaster, Richard; Silva, Nuno (2013). ExoMars Rover Vehicle Perception System Architecture and Test Results (PDF). 12th Symposium on Advanced Space Technologies in Robotics and Automation. 15–17 May 2013. Noordwijk, the Netherlands. European Space Agency.
23. Amos, Jonathan (27 March 2014). "'Mars yard' to test European rover". BBC News. Retrieved 29 March 2014.
24. Bauer, Markus (27 March 2014). "Mars yard ready for Red Planet rover". European Space Agency. Retrieved 29 March 2014.
25. "The ExoMars Rover Instrument Suite: PanCam - the Panoramic Camera". European Space Agency. 3 April 2013.
26. Griffiths, A. D.; Coates, A. J.; Jaumann, R.; Michaelis, H.; Paar, G.; Barnes, D.; Josset, J.-L.; Pancam Team (2006). "Context for the ESA ExoMars rover: the Panoramic Camera (PanCam) instrument". International Journal of Astrobiology. 5 (3): 269–275. Bibcode:2006IJAsB...5..269G. doi:10.1017/S1473550406003387.
27. Zolfagharifard, Ellie (15 October 2013). "How medieval stained-glass is creating the ultimate SPACE camera: Nanoparticles used in church windows will help scientists see Mars' true colours under extreme UV light". Daily Mail. Retrieved 29 December 2013.
28. Hand, Eric (3 March 2009). "NASA pursues Mars methane orbiter". Nature.com / Newsblog. Retrieved 13 October 2009.
29. "The ExoMars drill unit". European Space Agency. 13 July 2012.
30. "Sample Preparation and Distribution System (SPDS)". European Space Agency. 6 February 2013.
31. "The ExoMars Rover Instrument Suite". European Space Agency. 3 April 2013.
32. "Inside ExoMars". European Space Agency. August 2012. Retrieved 4 August 2012.
33. Clark, Stephen (21 November 2012). "European states accept Russia as ExoMars partner". Spaceflight Now.
34. "The ExoMars Rover Instrument Suite: RLS - Raman Spectrometer". European Space Agency. 3 April 2013.
35. Popp, J.; Schmitt, M. (2006). "Raman spectroscopy breaking terrestrial barriers!". Journal of Raman Spectroscopy. 35 (6): 18–21. Bibcode:2004JRSp...35..429P. doi:10.1002/jrs.1198.
36. Rull Pérez, Fernando; Martinez-Frias, Jesus (2006). "Raman spectroscopy goes to Mars" (PDF). Spectroscopy Europe. 18 (1): 18–21.
37. Corbel, C.; Hamram, S.; Ney, R.; Plettemeier, D.; Dolon, F.; Jeangeot, A.; Ciarletti, V.; Berthelier, J. (December 2006). "WISDOM: An UHF GPR on the Exomars Mission". Proceedings of the American Geophysical Union, Fall Meeting 2006. 51: 1218. Bibcode:2006AGUFM.P51D1218C. P51D–1218.
38. "The ExoMars Rover Instrument Suite: WISDOM - Water Ice and Subsurface Deposit Observation on Mars". European Space Agency. 3 April 2013.
39. "The ExoMars Rover Instrument Suite: MA_MISS - Mars Multispectral Imager for Subsurface Studies". European Space Agency. 3 April 2013.
40. "ExoMars 2018 mission". Институт Космических Исследований Space Research Institute. Retrieved 15 March 2016.
41. "The ExoMars Project". RussianSpaceWeb.com. Retrieved 22 October 2013.
42. Wielders, Arno; Delhez, Rob (June 2005). "X-ray Powder Diffraction on the Red Planet" (PDF). International Union of Crystallography Commission on Powder Diffraction Newsletter (30): 6–7.
43. Delhez, Rob; Marinangeli, Lucia; van der Gaast, Sjerry (June 2005). "Mars-XRD: the X-ray Diffractometer for Rock and Soil Analysis on Mars in 2011" (PDF). International Union of Crystallography Commission on Powder Diffraction Newsletter (30): 7–10.
44. "The ExoMars Rover Instrument Suite: Mars-XRD diffractometer". European Space Agency. 1 December 2011.
45. Skelley, Alison M.; Scherer, James R.; Aubrey, Andrew D.; Grover, William H.; Ivester, Robin H. C.; et al. (January 2005). "Development and evaluation of a microdevice for amino acid biomarker detection and analysis on Mars". Proceedings of the National Academy of Sciences. 102 (4): 1041–1046. Bibcode:2005PNAS..102.1041S. doi:10.1073/pnas.0406798102. PMC 545824. PMID 15657130.
46. Aubrey, Andrew D.; Chalmers, John H.; Bada, Jeffrey L.; Grunthaner, Frank J.; Amashukeli, Xenia; et al. (June 2008). "The Urey Instrument: An Advanced In Situ Organic and Oxidant Detector for Mars Exploration". Astrobiology. 8 (3): 583–595. Bibcode:2008AsBio...8..583K. doi:10.1089/ast.2007.0169. PMID 18680409.
47. Leinse, A.; Leeuwis, H.; Prak, A.; Heideman, R. G.; Borst, A. The life marker chip for the Exomars mission. 2011 ICO International Conference on Information Photonics. 18–20 May 2011. Ottawa, Ontario. pp. 1–2. doi:10.1109/ICO-IP.2011.5953740. ISBN 978-1-61284-315-5.
48. Martins, Zita (2011). "In situ biomarkers and the Life Marker Chip". Astronomy & Geophysics. 52 (1): 1.34–1.35. Bibcode:2011A&G....52a..34M. doi:10.1111/j.1468-4004.2011.52134.x.
49. Sims, Mark R.; Cullen, David C.; Rix, Catherine S.; Buckley, Alan; Derveni, Mariliza; et al. (November 2012). "Development status of the life marker chip instrument for ExoMars". Planetary and Space Science. 72 (1): 129–137. Bibcode:2012P&SS...72..129S. doi:10.1016/j.pss.2012.04.007.
50. "Four Candidate Landing Sites for ExoMars 2018". ESA. Space Ref. 1 October 2014. Retrieved 1 October 2014.
51. "Recommendation for the Narrowing of ExoMars 2018 Landing Sites". ESA. 1 October 2014. Retrieved 1 October 2014.
52. Amos, Jonathan (21 October 2015). "ExoMars rover: Landing preference is for Oxia Planum". BBC News. Retrieved 22 October 2015.
53. Atkinson, Nancy (21 October 2015). "Scientists Want ExoMars Rover to Land at Oxia Planum". Universe Today. Retrieved 22 October 2015.
54. "Exomars 2018 surface platform". European space agency. Retrieved 14 March 2016.

External links

• ExoMars rover at ESA.int
• ExoMars rover at CNES.fr
• ExoMars rover at NASA.gov