Editing Mars Science Laboratory (section)

=== Rover ===
[[File:Drawing-of-the-Mars-Science Laboratory.png|thumb|right|Color-coded rover diagram]]
{{Main|Curiosity (rover)#Specifications}}
''Curiosity'' rover has a mass of {{convert|899|kg|lb|abbr=on}}, can travel up to {{convert|90|m|ft|abbr=on}} per hour on its six-wheeled rocker-bogie system, is powered by a [[multi-mission radioisotope thermoelectric generator]] (MMRTG), and communicates in both [[X band]] and UHF bands.
* '''Computers:''' The two identical on-board rover computers, called "Rover Compute Element" (RCE), contain [[Radiation hardening|radiation-hardened]] memory to tolerate the extreme radiation from space and to safeguard against power-off cycles. Each computer's memory includes 256&nbsp;[[Kilobyte|KB]] of [[EEPROM]], 256&nbsp;[[Megabyte|MB]] of [[Dynamic random-access memory|DRAM]], and 2&nbsp;[[Gigabyte|GB]] of [[flash memory]].<ref name="Brains"/> This compares to 3&nbsp;MB of EEPROM, 128&nbsp;MB of DRAM, and 256&nbsp;MB of flash memory used in the Mars Exploration Rovers.<ref name="ieeecomputer"/>

:The RCE computers use the [[RAD750]] [[Central processing unit|CPU]] (a successor to the [[IBM RAD6000|RAD6000]] CPU used in the Mars Exploration Rovers) operating at 200&nbsp;MHz.<ref name="BAE Systems Computers to Manage Data Processing and Command For Upcoming Satellite Missions"/><ref name="E&ISNow&nbsp;— Media gets closer look at Manassas"/><ref name="cpuspeed"/> The RAD750 CPU is capable of up to 400&nbsp;[[Instructions per second#Million instructions per second|MIPS]], while the RAD6000 CPU is capable of up to 35&nbsp;MIPS.<ref name="RAD750brochure"/><ref name="RAD6000brochure"/> Of the two on-board computers, one is configured as backup, and will take over in the event of problems with the main computer.<ref name="Brains"/>

:The rover has an Inertial Measurement Unit (IMU) that provides 3-axis information on its position, which is used in rover navigation.<ref name="Brains"/> The rover's computers are constantly self-monitoring to keep the rover operational, such as by regulating the rover's temperature.<ref name="Brains"/> Activities such as taking pictures, driving, and operating the instruments are performed in a command sequence that is sent from the flight team to the rover.<ref name="Brains"/>

The rover's computers run [[VxWorks]], a [[real-time operating system]] from [[Wind River Systems]]. During the trip to Mars, VxWorks ran applications  dedicated to the navigation and guidance phase of the mission, and also had a pre-programmed software sequence for handling the complexity of the entry-descent-landing. Once landed, the applications were replaced with software for driving on the surface and performing scientific activities.<ref name="BrainTransplant"/><ref name="CuriosityVxWorks"/><ref name="cnn.com">{{cite news |title=Impressive' Curiosity landing only 1.5 miles off, NASA says |url=http://www.cnn.com/2012/08/10/us/mars-curiosity/index.html?eref=mrss_igoogle_cnn |access-date=August 10, 2012}}</ref>
:{{See also|Comparison of embedded computer systems on board the Mars rovers}}
[[File:Goldstone DSN antenna.jpg|thumb|right|[[Goldstone Deep Space Communications Complex|Goldstone]] antenna can receive signals.]]
[[File:Wheels of a working sibling to Curiosity rover.JPG|thumb|Wheels of a working sibling to ''Curiosity''. The Morse code pattern (for "[[Jet Propulsion Laboratory|JPL]]") is represented by small (dot) and large (dash) holes in three horizontal lines on the wheels. The code on each line is read from right to left.]]
* '''Communications:''' ''Curiosity'' is equipped with several means of communication, for redundancy. An [[X band]] [[Small Deep Space Transponder]] for communication directly to Earth via the [[NASA Deep Space Network]]<ref>{{cite web |url=http://mars.jpl.nasa.gov/msl/mission/communicationwithearth/ |title=Mars Science Laboratory, Communications With Earth |publisher=JPL}}</ref> and a [[ultra high frequency|UHF]] [[Electra (radio)|Electra]]-Lite [[software-defined radio]] for communicating with Mars orbiters.<ref name="DESCANSO"/>{{Rp|46}}  The X-band system has one radio, with a 15&nbsp;W power amplifier, and two antennas: a low-gain omnidirectional antenna that can communicate with Earth at very low data rates (15&nbsp;bit/s at maximum range), regardless of rover orientation, and a high-gain antenna that can communicate at speeds up to 32&nbsp;kbit/s, but must be aimed. The UHF system has two radios (approximately 9&nbsp;W transmit power<ref name="DESCANSO"/>{{Rp|81}}), sharing one omnidirectional antenna. This can communicate with the ''[[Mars Reconnaissance Orbiter]]'' (MRO) and ''[[2001 Mars Odyssey]]'' orbiter (ODY) at speeds up to 2&nbsp;Mbit/s and 256&nbsp;kbit/s, respectively, but each orbiter is only able to communicate with ''Curiosity'' for about 8 minutes per day.<ref name="Curiosity's data communication with Earth"/>  The orbiters have larger antennas and more powerful radios, and can relay data to Earth faster than the rover could do directly. Therefore, most of the data returned by ''Curiosity'' (MSL) is via the UHF relay links with MRO and ODY. The data return during the first 10 days was approximately 31 megabytes per day.

:Typically 225&nbsp;kbit/day of commands are transmitted to the rover directly from Earth, at a data rate of 1–2&nbsp;kbit/s, during a 15-minute (900 second) transmit window, while the larger volumes of data collected by the rover are returned via satellite relay.<ref name="DESCANSO"/>{{Rp|46}}  The one-way communication delay with Earth varies from 4 to 22 minutes, depending on the planets' relative positions, with 12.5 minutes being the average.<ref name="UT-20120817">{{cite news |url=http://www.universetoday.com/14824/distance-from-earth-to-mars/ |title=Distance from Earth to Mars |first=Fraser |last=Cain |date=August 10, 2012 |work=[[Universe Today]] |access-date=August 17, 2012}}</ref>

:At landing, telemetry was monitored by the ''2001 Mars Odyssey'' orbiter, ''Mars Reconnaissance Orbiter'' and ESA's ''[[Mars Express]]''. Odyssey is capable of relaying UHF telemetry back to Earth in real time. The relay time varies with the distance between the two planets and took 13:46 minutes at the time of landing.<ref name="WA-20120806" /><ref name="spaceflightnow" />
* '''Mobility systems:'''  ''Curiosity'' is equipped with six wheels in a [[rocker-bogie]] suspension, which also served as landing gear for the vehicle, unlike its smaller predecessors.<ref name="new wheels"/><ref>{{cite web |url=http://www.nasa.gov/mission_pages/msl/building_curiosity.html |title=Watch NASA's Next Mars Rover Being Built Via Live 'Curiosity Cam' |access-date=August 16, 2012 |date=September 13, 2011 |work=NASA |archive-date=November 26, 2011 |archive-url=https://web.archive.org/web/20111126035758/http://www.nasa.gov/mission_pages/msl/building_curiosity.html |url-status=dead }}</ref> The wheels are significantly larger ({{convert|50|cm|in|sp=us}} diameter) than those used on previous rovers. Each wheel has cleats and is independently actuated and geared, providing for climbing in soft sand and scrambling over rocks. The four corner wheels can be independently steered, allowing the vehicle to turn in place as well as execute arcing turns.<ref name="DESCANSO"/> Each wheel has a pattern that helps it maintain traction and leaves patterned tracks in the sandy surface of Mars. That pattern is used by on-board cameras to judge the distance traveled. The pattern itself is [[Morse code]] for "[[Jet Propulsion Laboratory|JPL]]" ('''•−−− •−−• •−••''').<ref name="aarlmorse"/> Based on the center of mass, the vehicle can withstand a tilt of at least 50 degrees in any direction without overturning, but automatic sensors will limit the rover from exceeding 30-degree tilts.<ref name="DESCANSO"/>
{{clear right}}

==== Instruments ====
{| class="sortable wikitable"  style="float:right; font-family:arial; font-size:11px;"
|-
! Main instruments
|-
| APXS – [[Alpha Particle X-ray Spectrometer]]
|-
| ChemCam – [[Chemistry and Camera complex]]
|-
| CheMin – [[CheMin|Chemistry and Mineralogy]]
|-
| DAN – [[Dynamic Albedo of Neutrons]]
|-
| Hazcam – [[Hazcam|Hazard Avoidance Camera]]
|-
| MAHLI – [[Mars Hand Lens Imager]]
|-
| MARDI – [[Mars Descent Imager]]
|-
| MastCam – [[Curiosity (rover)#Mast Camera (MastCam)|Mast Camera]]
|-
| MEDLI – [[Mars Science Laboratory#Specifications|MSL EDL Instrument]]
|-
| Navcam – [[Navcam|Navigation Camera]]
|-
| RAD – [[Radiation assessment detector]]
|-
| REMS – [[Rover Environmental Monitoring Station]]
|-
| SAM – [[Sample Analysis at Mars]]
|}
{{Main|Curiosity (rover)#Instruments}}
[[File:673885main PIA15986-full full.jpg|thumb|left|The shadow of ''Curiosity'' and [[Aeolis Mons|Aeolis Mons ("Mount Sharp")]]]]
The general analysis strategy begins with high resolution cameras to look for features of interest. If a particular surface is of interest, ''Curiosity'' can vaporize a small portion of it with an infrared laser and examine the resulting spectra signature to query the rock's elemental composition. If that signature intrigues, the rover will use its long arm to swing over a [[microscope]] and an [[X-ray spectroscopy|X-ray spectrometer]] to take a closer look. If the specimen warrants further analysis, ''Curiosity'' can drill into the boulder and deliver a powdered sample to either the [[Sample Analysis at Mars|SAM]] or the [[CheMin]] analytical laboratories inside the rover.<ref name="Gale Crater: Geological 'sweet shop' awaits Mars rover"/><ref name="MSLSAM"/><ref name="nasa5"/>
* '''[[Alpha Particle X-ray Spectrometer]] (APXS):''' This device can irradiate samples with [[alpha particle]]s and map the spectra of [[X-ray]]s that are re-emitted for determining the elemental composition of samples.
* '''[[CheMin]]:''' CheMin is short for 'Chemistry and Mineralogy', and it is an [[X-ray diffraction]] and [[X-ray fluorescence]] analyzer.<ref name='SciCorner'>{{cite web |url=http://msl-scicorner.jpl.nasa.gov/Instruments/CheMin/ |archive-url=https://web.archive.org/web/20090320125601/http://msl-scicorner.jpl.nasa.gov/Instruments/CheMin/ |url-status=dead |archive-date=March 20, 2009 |title=MSL Science Corner – Chemistry & Mineralogy (CheMin) |access-date=August 24, 2012 |first=David Blake |last=NASA Ames Research Center |year=2011}}</ref><ref name='SciPackage'>{{cite web |url=http://earthweb.ess.washington.edu/ess-306/MSL-PIP.pdf |title=Mars Science Laboratory Participating Scientists Program – Proposal Information Package. |access-date=August 24, 2012 |author=The MSL Project Science Office |date=December 14, 2010 |work=[[JPL]] – NASA |publisher=Washington University}}</ref><ref name='Field deployment'>{{cite journal |title=Field Deployment of A Portable XRD/XRF Iinstrument On Mars Analog Terrain |journal=Advances in X-ray Analysis |author=Sarrazin P. |author2=Blake D. |author3=Feldman S. |author4=Chipera S. |author5=Vaniman D. |author6=Bish D. |volume=48 |url=http://www.icdd.com/resources/axa/vol48/V48_27.pdf |access-date=August 24, 2012 |quote=International Centre for Diffraction Data 2005 |archive-date=May 12, 2013 |archive-url=https://web.archive.org/web/20130512004452/http://www.icdd.com/resources/axa/vol48/V48_27.pdf |url-status=dead }}</ref> It will identify and quantify the minerals present in rocks and soil and thereby assess the involvement of [[Water on Mars|water]] in their formation, deposition, or alteration.<ref name='SciPackage'/> In addition, CheMin data will be useful in the search for potential mineral [[biosignature]]s, energy sources for life or indicators for past habitable environments.<ref name='SciCorner'/><ref name='SciPackage'/>
* '''[[Sample Analysis at Mars]] (SAM):''' The SAM instrument suite will analyze [[Organic compound|organics]] and gases from both atmospheric and solid samples.<ref name="MSLSAM"/><ref name="nasa5"/> This include oxygen and carbon [[isotope]] ratios in carbon dioxide (CO<sub>2</sub>) and [[Atmosphere of Mars#Methane|methane (CH<sub>4</sub>) in the atmosphere of Mars]] in order to distinguish between their [[Geochemistry|geochemical]] or [[biology|biological]] origin.<ref name="MSLSAM"/><ref name="SAM">{{cite web |url=http://ael.gsfc.nasa.gov/marsSAM.shtml |title=Sample Analysis at Mars (SAM) Instrument Suite |access-date=October 9, 2008 |date=October 2008 |publisher=NASA |url-status=dead |archive-url=https://web.archive.org/web/20070222092231/http://ael.gsfc.nasa.gov/marsSAM.shtml |archive-date=February 22, 2007 }}</ref><ref>{{cite web |url=http://www.astrobio.net/news/modules.php?op=modload&name=News&file=article&sid=2765&mode=thread&order=0&thold=0 |title=Making Sense of Mars Methane |access-date=October 8, 2008 |last=Tenenbaum |first=D. |date=June 9, 2008 |work=[[NASA|Astrobiology Magazine]] |archive-url=https://web.archive.org/web/20120531234217/http://www.astrobio.net/exclusive/2765/making-sense-of-mars-methane |archive-date=2012-05-31 |url-status=usurped}}</ref><ref>
{{cite journal |last1=Tarsitano |first1=C. G. |last2=Webster |first2=C. R. |year=2007 |title=Multilaser Herriott cell for planetary tunable laser spectrometers |journal=[[Applied Optics]] |volume=46 |issue=28 |pages=6923–6935 |bibcode=2007ApOpt..46.6923T |doi=10.1364/AO.46.006923 |pmid=17906720|s2cid=45886335 }}</ref><ref name="Mah2012">
{{cite journal |last1=Mahaffy |first1=Paul R. |year=2012 |title=The Sample Analysis at Mars Investigation and Instrument Suite |journal=[[Space Science Reviews]] |volume=170 |issue=1–4 |pages=401–478 |bibcode=2012SSRv..170..401M |doi=10.1007/s11214-012-9879-z |display-authors=etal|doi-access=free |hdl=2060/20120002542 |hdl-access=free }}</ref>
[[File:PIA17601-Comparisons-RadiationExposure-MarsTrip-20131209.png|thumb|left|Comparison of Radiation Doses – includes the amount detected on the trip from Earth to Mars by the [[Radiation assessment detector|RAD]] on the MSL (2011–2013)<ref name="SCI-20130531a" /><ref name="SCI-20130531b" /><ref name="NYT-20130530" />]]
* '''[[Radiation assessment detector|Radiation Assessment Detector]] (RAD):''' This instrument was the first of ten MSL instruments to be turned on. Both en route and on the planet's surface, it characterized the broad spectrum of [[Cosmic ray|radiation]] encountered in the Martian environment. Turned on after launch, it recorded several radiation spikes caused by the Sun.<ref name="rad"/> NASA scientists reported that a possible [[human mission to Mars]] may involve a great [[radiation|radiation risk]] due to [[radiation|energetic particle radiation]] detected by the RAD while traveling from the [[Earth]] to [[Mars]].<ref name="SCI-20130531a">{{cite journal |last=Kerr |first=Richard |title=Radiation Will Make Astronauts' Trip to Mars Even Riskier |date=May 31, 2013 |journal=[[Science (journal)|Science]] |volume=340 |number=6136 |page=1031 |doi=10.1126/science.340.6136.1031 |pmid=23723213|bibcode=2013Sci...340.1031K }}</ref><ref name="SCI-20130531b">{{cite journal |last=Zeitlin|first=C. |title=Measurements of Energetic Particle Radiation in Transit to Mars on the Mars Science Laboratory |journal=[[Science (journal)|Science]] |date=May 31, 2013 |volume=340 |number=6136 |pages=1080–1084 |doi=10.1126/science.1235989 |pmid=23723233 |display-authors=etal |bibcode=2013Sci...340.1080Z|s2cid=604569 |url=https://semanticscholar.org/paper/d4f68022dd4b96755933bccdc586bbeb2e031eb3 }}</ref><ref name="NYT-20130530">{{cite news |last=Chang |first=Kenneth |title=Data Point to Radiation Risk for Travelers to Mars |url=https://www.nytimes.com/2013/05/31/science/space/data-show-higher-cancer-risk-for-mars-astronauts.html |date=May 30, 2013 |work=The New York Times |access-date=May 31, 2013}}</ref>
[[File:PIA13580 crop.jpg|thumb|right|150px|{{center|The [[Radiation assessment detector|RAD]] on [[Curiosity (rover)|''Curiosity'']]}}]]
* '''[[Dynamic Albedo of Neutrons]] (DAN):''' A pulsed [[neutron source]] and detector for measuring [[hydrogen]] or ice and water at or near the Martian surface.<ref name="The Dynamic Albedo of Neutrons (DAN) Experiment for NASA's 2009 Mars Science Laboratory">{{cite journal |doi=10.1089/ast.2007.0157 |title=The Dynamic Albedo of Neutrons (DAN) Experiment for NASA's 2009 Mars Science Laboratory |year=2008 |last1=Litvak |first1=M.L. |last2=Mitrofanov |first2=I.G. |last3=Barmakov |first3=Yu.N. |last4=Behar |first4=A. |last5=Bitulev |first5=A. |last6=Bobrovnitsky |first6=Yu. |last7=Bogolubov |first7=E.P. |last8=Boynton |first8=W.V. |last9=Bragin |first9=S.I. |display-authors=8 |journal=Astrobiology |volume=8 |issue=3 |pages=605–12 |pmid=18598140 |bibcode=2008AsBio...8..605L}}</ref><ref name="MSLDAN">{{cite web |url=http://msl-scicorner.jpl.nasa.gov/Instruments/DAN/ |archive-url=https://web.archive.org/web/20090320125107/http://msl-scicorner.jpl.nasa.gov/Instruments/DAN/ |url-status=dead |archive-date=March 20, 2009 |title=MSL Science Corner: Dynamic Albedo of Neutrons (DAN) |publisher=NASA/JPL |access-date=September 9, 2009}}</ref> On August 18, 2012 (sol {{age in sols|2012|8|6|2012|08|18}}) the Russian science instrument, DAN, was turned on,<ref name=cbs>{{cite web |url=https://www.cbsnews.com/news/curiositys-mars-travel-plans-tentatively-mapped/ |title=Curiosity's Mars travel plans tentatively mapped |website=[[CBS News]] |date=August 18, 2012 }}</ref> marking the success of a Russian-American collaboration on the surface of Mars and the first working Russian science instrument on the Martian surface since [[Mars 3]] stopped transmitting over forty years ago.<ref>{{cite web |url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1971-049A |title=NASA - NSSDCA - Spacecraft - Details }}</ref> The instrument is designed to detect subsurface water.<ref name=cbs/>
* '''[[Rover Environmental Monitoring Station]] (REMS):''' Meteorological package and an [[ultraviolet]] sensor provided by [[Ministry of Education (Spain)|Spain]] and [[Finland]].<ref name="Rover Environmental Monitoring Station for MSL mission"/> It measures humidity, pressure, temperatures, wind speeds, and ultraviolet radiation.<ref name="Rover Environmental Monitoring Station for MSL mission">{{cite web |publisher=Pierre und Marie Curie University |url=http://www-mars.lmd.jussieu.fr/paris2011/abstracts/gomez-elvira_paris2011.pdf |title=Rover Environmental Monitoring Station for MSL mission |work=4th International workshop on the Mars Atmosphere: modelling and observations |date=February 2011 |access-date=August 6, 2012}}</ref>
* '''Cameras:''' ''Curiosity'' has seventeen cameras overall.<ref name="nasa6"/> 12 engineering cameras (Hazcams and Navcams) and five science cameras. MAHLI, MARDI, and MastCam cameras were developed by [[Malin Space Science Systems]] and they all share common design components, such as on-board electronic [[image processing|imaging processing]] boxes, 1600×1200 [[Charge-coupled device|CCDs]], and a [[Bayer filter|RGB Bayer pattern filter]].<ref name="LPSCMast"/><ref name="MastCam"/><ref name="MAHLI"/><ref name="MARDI"/><ref name="MastCamDescription"/><ref name="NovEmail"/>
** '''MastCam''': This system provides multiple spectra and [[24-bit color|true-color]] imaging with two cameras.
** '''[[Mars Hand Lens Imager]] (MAHLI)''': This system consists of a camera mounted to a robotic arm on the rover, used to acquire microscopic images of rock and soil. It has white and ultraviolet LEDs for illumination.
* '''ChemCam:''' Designed by Roger Wiens  is a system of remote sensing instruments used to erode the Martian surface up to 10 meters away and measure the different components that make up the land.<ref>{{Cite book|title=The design and engineering of Curiosity : how the Mars Rover performs its job|last=Emily|first=Lakdawalla|isbn=9783319681467|location=Cham, Switzerland|oclc=1030303276|date = March 27, 2018}}</ref> The payload includes the first [[laser-induced breakdown spectroscopy]] (LIBS) system to be used for planetary science, and ''Curiosity''{{'s}} fifth science camera, the remote micro-imager (RMI). The RMI provides black-and-white images at 1024×1024 resolution in a 0.02 radian (1.1-degree) field of view.<ref>{{cite web |url=http://www.msl-chemcam.com/index.php?menu=inc&page_consult=textes&rubrique=64&sousrubrique=224&soussousrubrique=0&titre_url=ChemCam%20-%20How%20does%20ChemCam%20work? |title=ChemCam - ChemCam - How does ChemCam work? }}</ref> This is approximately equivalent to a 1500&nbsp;mm lens on a [[135 film|35 mm]] camera.
[[File:Gravel-covered martian surface.jpg|thumb|right|MARDI views the surface.]]
* '''Mars Descent Imager (MARDI)''': During the descent to the Martian surface, MARDI acquired 4 color images per second, at 1600×1200 pixels, with a 0.9-millisecond exposure time, from before heatshield separation at 3.7&nbsp;km altitude, until a few seconds after touchdown. This provided engineering information about both the motion of the rover during the descent process, and science information about the terrain immediately surrounding the rover. NASA descoped MARDI in 2007, but Malin Space Science Systems contributed it with its own resources.<ref>{{cite web |url=http://msl-scicorner.jpl.nasa.gov/Instruments/MARDI/ |archive-url=https://web.archive.org/web/20090320130148/http://msl-scicorner.jpl.nasa.gov/Instruments/MARDI/ |url-status=dead |archive-date=2009-03-20 |title=MSL Science Corner: Mars Descent Imager (MARDI) |last=[NULL] }}</ref> After landing it could take {{convert|1.5|mm|in|abbr=on}} per pixel views of the surface,<ref>{{cite web |url=http://www.exploremars.org/msl-picture-of-the-day-t-27-days-instruments-mardi |archive-url=https://web.archive.org/web/20130119035203/http://www.exploremars.org/msl-picture-of-the-day-t-27-days-instruments-mardi |url-status=dead |archive-date=January 19, 2013 |title=MSL Picture of the Day: T-27 Days: instruments: MARDI }}</ref> the first of these post-landing photos were taken by August 27, 2012 (sol {{age in sols|2012|8|6|2012|08|27}}).<ref>{{cite web |url=http://mars.jpl.nasa.gov/msl/multimedia/raw/?s=21&camera=MARDI |title=Raw Images - Mars Science Laboratory |first=JPL |last=NASA }}</ref>
* Engineering cameras: There are 12 additional cameras that support mobility:
** '''Hazard avoidance cameras (Hazcams):''' The rover has a pair of black and white navigation cameras ([[Hazcam]]s) located on each of its four corners.<ref name="wired">{{Cite journal |url=https://www.wired.com/wiredscience/2012/08/curiosity-mars-rover-cameras/ |title=The Photo-Geek's Guide to Curiosity Rover's 17 Cameras |date=August 7, 2012 |first=Adam |last=Mann |journal=Wired Science |access-date=August 15, 2012}}</ref> These provide close-up views of potential obstacles about to go under the wheels.
** '''Navigation cameras (Navcams):''' The rover uses two pairs of black and white navigation cameras mounted on the mast to support ground navigation.<ref name="wired"/> These provide a longer-distance view of the terrain ahead.