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'''''Philae''''', '''Philae (robot)''' hay '''Philae (tàu vũ trụ)''' là ({{IPAc-en|'|f|ai|l|i:}} or {{IPAc-en|'|f|i:|l|eɪ}}<ref>{{cite web|last1=Ellis|first1=Ralph|title=Space probe scores a 310-million-mile bull's-eye with comet landing|url=http://www.cnn.com/2014/11/12/world/comet-landing-countdown/index.html|website=cnn.com|publisher=CNN|date=12 November 2014|accessdate=13 November 2014|format=pronunciation used in video}}</ref>)
==Design==
[[File:Rosetta and Philae (crop).jpg|thumb|left|''Rosetta'' and ''Philae'']]
The lander was designed to deploy from the main spacecraft body and descend from an orbit of {{convert|22.5|km|0}} along a [[Trajectory of a projectile|ballistic trajectory]].<ref name="bbcnews20140926">{{cite news |url=http://www.bbc.com/news/science-environment-29380448 |title=Rosetta: Date fixed for historic comet landing attempt |work=BBC News |first=Jonathan |last=Amos |date=26 September 2014 |accessdate=29 September 2014}}</ref> It would touch down on the comet's surface at a velocity of around {{convert|1|m/s|km/h mph}}.<ref name="bbcnews20140825">{{cite news |url=http://www.bbc.com/news/science-environment-28923010 |title=Rosetta mission: Potential comet landing sites chosen |work=BBC News |first=Jonathan |last=Amos |date=25 August 2014 |accessdate=25 August 2014}}</ref> The legs were designed to dampen the initial impact to avoid bouncing as the comet's escape velocity is only around {{convert|0.5|m/s|km/h mph|abbr=on}},<ref name="astrowatch">{{cite web |url=http://www.astrowatch.net/2014/09/the-analysis-of-comet-67pchuryumov.html |title=The Analysis of Comet 67P/Churyumov-Gerasimenko |work=Astrowatch.net |first=Giuseppe |last=Conzo |date=2 September 2014 |accessdate=4 October 2014}}</ref> and the impact energy would drive ice screws into the surface.<ref name="">{{cite web |url=https://www.mps.mpg.de/3086295/Philae-Blog |title=About the Upcoming Philae Separation, Descent and Landing |publisher=[[Max Planck Institute for Solar System Research]] |first=Hermann |last=Böhnhardt |date=10 November 2014 |accessdate=11 November 2014}}</ref> ''Philae'' would then fire two [[harpoon]]s into the surface at {{convert|70|m/s|km/h mph|abbr=on}} to anchor itself.<ref name="Biele2009">{{cite book |chapterurl=http://books.google.com/books?id=5YIPCbnTCeMC&pg=PA297&lpg=PA297 |chapter=The Strength of Cometary Surface Material: Relevance of Deep Impact Results for Philae Landing on a Comet |title=Deep Impact as a World Observatory Event: Synergies in Space, Time, and Wavelength |publisher=Springer |series=ESO Astrophysics Symposia |first1=J. |last1=Biele |first2=S. |last2=Ulamec |first3=L. |last3=Richter |first4=E. |last4=Kührt |first5=J. |last5=Knollenberg |first6=D. |last6=Möhlmann |editor1-first=Hans Ulrich |editor1-last=Käufl |editor2-first=Christiaan |editor2-last=Sterken |p=297 |year=2009 |isbn=978-3-540-76958-3 |bibcode=2009diwo.conf..285B |doi=10.1007/978-3-540-76959-0_38}}</ref><ref name="Biele2013">{{cite conference |url=http://www.lpi.usra.edu/meetings/lpsc2013/pdf/1392.pdf |title=Preparing for Landing on a Comet - The Rosetta Lander Philae |conference=44th Lunar and Planetary Science Conference. 18–22 March 2013. The Woodlands, Texas. |first1=Jens |last1=Biele |first2=Stephan |last2=Ulamec |year=2013 |id=LPI Contribution No. 1719 |bibcode=2013LPI....44.1392B}}</ref> A thruster on top of Philae would fire to lessen the bounce upon impact and to reduce the recoil from harpoon firing.<ref name=CS1>{{cite news |title=Will Philae successfully land on comet? Thruster trouble heightens drama. |author= |url= http://www.csmonitor.com/Science/2014/1112/Will-Philae-successfully-land-on-comet-Thruster-trouble-heightens-drama|newspaper=Christian Science Monitor |work= |date=12 November 2014}}</ref>
Communications with [[Earth]] will use the orbiter spacecraft as a [[relay station]] to reduce the electrical power needed. The mission duration on the surface is planned to be at least one week, but an extended mission lasting months is possible.
The main structure of the lander is made from [[Carbon-fiber-reinforced polymer|carbon fiber]], shaped into a plate maintaining mechanical stability, a platform for the science instruments, and a [[hexagon]]al "sandwich" to connect all the parts. The total mass is about {{convert|100|kg|lb}}. Its "hood" is covered with [[solar cell]]s for power generation.<ref name="Biele2002"/>
[[File:PIA18809.jpg|thumb|''Philae'' landing site Agilkia (Site J)]]
It was originally planned to rendezvous with the comet [[46P/Wirtanen]]. A failure in a previous [[Ariane 5]] launch vehicle closed the [[launch window]] to reach the comet. It necessitated a change in target to the comet [[67P/Churyumov–Gerasimenko]]. The larger mass of comet 67P/C-G and the resulting increased impact velocity required that the landing gear of the redesigned lander be strengthened, in order for the spacecraft and its delicate scientific instruments to survive the landing.
{| class="wikitable"
|-
! Spacecraft component !! Mass<ref name="Bibring2007"/>{{rp|208}}
|-
| [[Spacecraft thermal control|Thermal Control System]] || {{convert|3.9|kg|lb|abbr=on}}
|-
| Power System || {{convert|12.2|kg|lb|abbr=on}}
|-
| Active Descent System || {{convert|4.1|kg|lb|abbr=on}}
|-
| [[Reaction wheel|Flywheel]] || {{convert|2.9|kg|lb|abbr=on}}
|-
| Landing Gear || {{convert|10|kg|lb|0|abbr=on}}
|-
| Anchoring System || {{convert|1.4|kg|lb|abbr=on}}
|-
| Central Data Management System || {{convert|2.9|kg|lb|abbr=on}}
|-
| Telecommunications System || {{convert|2.4|kg|lb|abbr=on}}
|-
| Common Electronics Box || {{convert|9.8|kg|lb|abbr=on}}
|-
| Mechanical Support System, Harness, balancing mass || {{convert|3.6|kg|lb|abbr=on}}
|-
| [[#Instruments|Scientific payload]] || {{convert|26.7|kg|lb|abbr=on}}
|-
! Sum !! {{convert|97.9|kg|lb|abbr=on}}
|}
===Power management===
''Philae'' power management has been planned for two phases. In the first phase, the lander will operate solely on battery power. In the second phase, "it will run on backup batteries recharged by solar cells".<ref name=":1" />
===Instruments===
[[File:Atterrisseur-Philae-15494442575 099c1ff083 o.png|thumb|''Philae''{{'s}} instruments]]
The science payload of the lander consists of ten instruments massing {{convert|26.7|kg|lb}}, making up just over one-fourth of the mass of the lander.<ref name="Bibring2007"/>
; [[APXS]] : The ''Alpha Particle X-ray Spectrometer'' detects alpha particles and X-rays, which provide information on the elemental composition of the comet's surface.<ref>{{cite web |url=http://www.esa.int/Our_Activities/Space_Science/Rosetta/APXS |title=APXS |publisher=European Space Agency |accessdate=26 August 2014 }}</ref> The instrument is an improved version of the APXS of the [[Mars Pathfinder]].
; COSAC : The ''COmetary SAmpling and Composition'' instrument is a combined [[gas chromatograph]] and time-of-flight [[mass spectrometry|mass spectrometer]] to perform analysis of soil samples and determine the content of volatile components.<ref name="Gosmann2005">{{cite journal |title=COSAC Onboard Rosetta: A Bioastronomy Experiment for the Short-Period Comet 67P/Churyumov-Gerasimenko |journal=Astrobiology |first1=Fred |last1=Goesmann |first2=Helmut |last2=Rosenbauer |first3=Reinhard |last3=Roll |first4=Hermann |last4=Böhnhardt |volume=5 |issue=5 |pages=622–631 |date=October 2005 |doi=10.1089/ast.2005.5.622 |bibcode=2005AsBio...5..622G |pmid=16225435}}</ref><ref>{{cite web |url=http://www.esa.int/Our_Activities/Space_Science/Rosetta/COSAC |title=COSAC |publisher=European Space Agency |accessdate=26 August 2014}}</ref>
; Ptolemy : An instrument measuring [[stable isotope ratio]]s of key volatiles on the comet's nucleus.<ref name="Wright2007">{{cite journal |title=Ptolemy: An Instrument to Measure Stable Isotopic Ratios of Key Volatiles on a Cometary Nucleus |journal=Space Science Reviews |first1=I. P. |last1=Wright |first2=S. J. |last2=Barber |first3=G. H. |last3=Morgan |first4=A. D. |last4=Morse |first5=S. |last5=Sheridan |first6=D. J. |last6=Andrews |first7=J. |last7=Maynard |first8=D. |last8=Yau |first9=S. T. |last9=Evans |first10=M. R. |last10=Leese |first11=J. C. |last11=Zarnecki |first12=B. J. |last12=Kent |first13=N. R. |last13=Waltham |first14=M. S. |last14=Whalley |first15=S. |last15=Heys |first16=D. L. |last16=Drummond |first17=R. L. |last17=Edeson |first18=E. C. |last18=Sawyer |first19=R. F. |last19=Turner |first20=C. T. |last20=Pillinger |display-authors=5 |volume=128 |issue=1-4 |pages=363–381 |date=February 2007 |doi=10.1007/s11214-006-9001-5 |bibcode=2007SSRv..128..363W}}</ref><ref name="Andrews2006">{{cite conference |url=http://www.lpi.usra.edu/meetings/lpsc2006/pdf/1937.pdf |title=''Ptolemy'': An Instrument aboard the Rosetta Lander Philae, to Unlock the Secrets of the Solar System |conference=37th Lunar and Planetary Science Conference. 13–17 March 2006. League City, Texas. |first1=D. J. |last1=Andrews |first2=S. J. |last2=Barber |first3=A. D. |last3=Morse |first4=S. |last4=Sheridan |first5=I. P. |last5=Wright |first6=G. H. |last6=Morgan |display-authors=5 |year=2006}}</ref>
; ÇIVA : The ''Comet Nucleus Infrared and Visible Analyzer'' is a group of six identical micro-cameras that take panoramic pictures of the surface. Each camera has a 1024×1024 pixel CCD detector.<ref name="nssdc-civa">{{cite web |url=http://nssdc.gsfc.nasa.gov/nmc/experimentDisplay.do?id=PHILAE%20%20%20-01 |title=Comet nucleus Infrared and Visible Analyzer (CIVA) |publisher=[[National Space Science Data Center]] |accessdate=28 August 2014}}</ref> A [[spectrometer]] studies the composition, texture and albedo (reflectivity) of samples collected from the surface.<ref>{{cite web |url=http://www.esa.int/Our_Activities/Space_Science/Rosetta/CIVA |title=ÇIVA |publisher=European Space Agency |accessdate=26 August 2014}}</ref>
; ROLIS : The ''Rosetta Lander Imaging System'' is a [[Charge-coupled device|CCD camera]] that will obtain high-resolution images during descent and stereo panoramic images of areas sampled by other instruments.<ref>{{cite web |url=http://www.esa.int/Our_Activities/Space_Science/Rosetta/ROLIS |title=ROLIS |publisher=European Space Agency |accessdate=26 August 2014}}</ref> The CCD detector consists of 1024×1024 pixels.<ref>{{cite web |url=http://nssdc.gsfc.nasa.gov/nmc/experimentDisplay.do?id=PHILAE%20%20%20-02 |title=Rosetta Lander Imaging System (ROLIS) |publisher=[[National Space Science Data Center]] |accessdate=28 August 2014}}</ref>
; [[CONSERT]] : The ''COmet Nucleus Sounding Experiment by Radiowave Transmission'' experiment will use electromagnetic wave propagation to determine the comet's internal structure. A [[radar]] on ''Rosetta'' will transmit a signal through the nucleus to be received by a detector on ''Philae''.<ref name="Kofman2007">{{cite journal |title=The Comet Nucleus Sounding Experiment by Radiowave Transmission (CONSERT): A Short Description of the Instrument and of the Commissioning Stages |journal=Space Science Reviews |first1=W. |last1=Kofman |first2=A. |last2=Herique |first3=J.-P. |last3=Goutail |first4=T. |last4=Hagfors |first5=I. P. |last5=Williams |first6=E. |last6=Nielsen |first7=J.-P. |last7=Barriot |first8=Y. |last8=Barbin |first9=C. |last9=Elachi |first10=P. |last10=Edenhofer |first11=A.-C. |last11=Levasseur-Regourd |first12=D. |last12=Plettemeier |first13=G. |last13=Picardi |first14=R. |last14=Seu |first15=V. |last15=Svedhem |display-authors=5 |volume=128 |issue=1-4 |pages=413–432 |date=February 2007 |doi=10.1007/s11214-006-9034-9 |bibcode=2007SSRv..128..413K}}</ref><ref>{{cite web |url=http://www.esa.int/Our_Activities/Space_Science/Rosetta/CONSERT2 |title=CONCERT |publisher=European Space Agency |accessdate=26 August 2014 }}</ref>
; MUPUS : The ''MUlti-PUrpose Sensors for Surface and Sub-Surface Science'' instrument will measure the density, thermal and mechanical properties of the comet's surface.<ref>{{cite web |url=http://www.esa.int/Our_Activities/Space_Science/Rosetta/MUPUS |title=MUPUS |publisher=European Space Agency |accessdate=26 August 2014 }}</ref>
; ROMAP : The ''Rosetta Lander Magnetometer and Plasma Monitor'' is a [[magnetometer]] and [[Plasma (physics)|plasma]] sensor to study the nucleus' magnetic field and its interactions with the [[solar wind]].<ref>{{cite web |url=http://www.esa.int/Our_Activities/Space_Science/Rosetta/ROMAP |title=ROMAP |publisher=European Space Agency |accessdate=26 August 2014 }}</ref>
; SESAME : The ''Surface Electric Sounding and Acoustic Monitoring Experiments'' will use three instruments to measure properties of the comet's outer layers. The ''Cometary Acoustic Sounding Surface Experiment'' (CASSE) measures the way in which sound travels through the surface. The ''Permittivity Probe'' (PP) investigates its electrical characteristics, and the ''Dust Impact Monitor'' (DIM) measures dust falling back to the surface.<ref name="Seidensticker2007">{{cite journal |title=Sesame – An Experiment of the Rosetta Lander Philae: Objectives and General Design |journal=Space Science Reviews |first1=K. J. |last1=Seidensticker |first2=D. |last2=Möhlmann |first3=I. |last3=Apathy |first4=W. |last4=Schmidt |first5=K. |last5=Thiel |first6=W. |last6=Arnold |first7=H.-H. |last7=Fischer |first8=M. |last8=Kretschmer |first9=D. |last9=Madlener |first10=A. |last10=Péter |first11=R. |last11=Trautner |first12=S. |last12=Schieke |display-authors=5 |volume=128 |issue=1-4 |pages=301–337 |date=February 2007 |doi=10.1007/s11214-006-9118-6 |bibcode=2007SSRv..128..301S}}</ref>
; SD2 : The ''Drill, Sample, and Distribution subsystem'' obtains soil samples from the comet at depths of {{convert|0|to|230|mm|in}} and distributes them to the Ptolemy, COSAC, and ÇIVA subsystems for analyses.<ref>{{cite web |url=http://www.esa.int/Our_Activities/Space_Science/Rosetta/SD2 |title=SD2 |publisher=European Space Agency |accessdate=26 August 2014 }}</ref> The system contains four types of subsystems: drill, carousel, ovens, and volume checker.<ref>{{cite web |url=http://www.aero.polimi.it/SD2/ |title=Philae SD2 |publisher=Politecnico di Milano |accessdate=11 August 2014}}</ref> There are a total of 26 platinum ovens to heat samples—10 medium temperature {{convert|180|C|F}} and 16 high temperature {{convert|800|C|F}}—and one oven to clear the drill bit for reuse.<ref>{{cite web |url=http://www.aero.polimi.it/SD2/?SD2:System_Overview:Ovens |title=Ovens |publisher=Politecnico di Milano |accessdate=11 August 2014}}</ref>
==Hình ảnh==
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