Mars Science Laboratory: Difference between revisions

Revision as of 08:35, 6 August 2012

Revision as of 08:36, 6 August 2012

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:''Curiosity's'' power generator is the latest RTG generation built by [[Boeing]], called the "[[Multi-Mission Radioisotope Thermoelectric Generator]]" or MMRTG.<ref name="MSLPower">{{cite web |url=http://marsprogram.jpl.nasa.gov/msl/technology/tech_power.html |title=Technologies of Broad Benefit: Power |accessdate=September 20, 2008 |archiveurl = http://web.archive.org/web/20080614071650/http://marsprogram.jpl.nasa.gov/msl/technology/tech_power.html <!-- Bot retrieved archive --> |archivedate = June 14, 2008}}</ref> Based on classical RTG technology, it represents a more flexible and compact development step,<ref name="MSLPower"/> and is designed to produce 125 watts of electrical power from about 2000 watts of thermal power at the start of the mission.<ref name="MMRTG"/><ref name="MarsExplorationMMRTG"/> The MMRTG produces less power over time as its plutonium fuel decays: at its minimum lifetime of 14 years, electrical power output is down to 100 watts.<ref>{{cite web|url=http://mars.jpl.nasa.gov/msl/mission/technology/technologiesofbroadbenefit/power/ |title=Mars Science Laboratory – Technologies of Broad Benefit: Power |accessdate=April 23, 2011 |publisher=NASA/JPL }}</ref><ref>{{cite web|url=http://pdf.aiaa.org/preview/CDReadyMIECEC06_1309/PV2006_4187.pdf |title=Overview of NASA Program on Development of Radioisotope Power Systems with High Specific Power |author=Ajay K. Misra |date=June 26, 2006 |accessdate=May 12, 2009 |publisher=NASA/JPL }}</ref> The MSL will generate 2.5 [[kilowatt hour]]s per day, much more than the [[Mars Exploration Rover]]s, which can generate about 0.6 kilowatt hours per day.

* '''Heat rejection system:''' The temperatures can vary from +30−127 °C to −127+30 °C (+86−197 °F to −197+86 °F). Therefore, the heat rejection system (HRS) uses fluid pumped through {{convert|60|m|ft|abbr=on}} of tubing in the MSL body so that sensitive components are kept at optimal temperatures.<ref name=HRS>{{cite web| author=Susan Watanabe | url=http://www1.nasa.gov/mission_pages/mars/images/20081209_msl.html |title=Keeping it Cool (...or Warm!) |date=August 9, 2009 |publisher=NASA/JPL |accessdate=January 19, 2011}}</ref> Other methods of heating the internal components include using radiated heat generated from the components in the craft itself, as well as excess heat from the MMRTG unit. The HRS also has the ability to cool components if necessary.<ref name=HRS/>

* '''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 [[Kilobyte|KB]] of [[EEPROM]], 256 [[Megabyte|MB]] of [[Dynamic random-access memory|DRAM]], and 2 [[Gigabyte|GB]] of [[flash memory]].<ref name="Brains">{{cite web|url=http://marsprogram.jpl.nasa.gov/msl/mission/rover/brains/ |title=Mars Science Laboratory: Mission: Rover: Brains |accessdate=March 27, 2009 |publisher=NASA/JPL }}</ref> This compares to 3 MB of EEPROM, 128 MB of DRAM, and 256 MB of flash memory used in the Mars Exploration Rovers.<ref name="ieeecomputer">{{cite journal | last=Bajracharya | first=Max | coauthors=Mark W. Maimone; Daniel Helmick | title=Autonomy for Mars rovers: past, present, and future | journal=Computer | volume=41| issue=12 | page=45 | doi= 10.1109/MC.2008.9| month=December | year=2008 | issn=0018-9162}}</ref>