DOCSLIB.ORG

Article 10 Mars Exploration Rover Telecommunications

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Article 10 Mars Exploration Rover Telecommunications DESCANSO Design and Performance Summary Series Article 10 Mars Exploration Rover Telecommunications Jim Taylor Andre Makovsky Andrea Barbieri Ramona Tung Polly Estabrook A. Gail Thomas Jet Propulsion Laboratory California Institute of Technology Pasadena, California National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California October 2005 This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Prologue Mars Exploration Rovers: Twelve Wheels on the Ground The cover image is an artist’s rendition of one of the rovers deployed on the surface of Mars. (A version of this picture with the parts called out appears at the end of Section 1.) In the cover image, the communications antennas are prominent. The High-Gain Antenna (HGA) for direct-to-Earth (DTE) communications with the Deep Space Network (DSN) is the large disk to the right, facing up and out. The Low-Gain Antenna (LGA) is the mast to the left of the HGA. The Ultrahigh-Frequency (UHF) Antenna, for communicating with Mars orbiters, is the thinner vertical rod to the left of the LGA. The Panoramic Camera (Pancam) is mounted on the large, light-colored mast in the foreground, which was also a factor in the rover’s communications with the DSN. The picture above, from [1], is a self-portrait of the Spirit rover on the surface of Mars, a mosaic made up of about 100 separate images taken by the rover’s Pancam on sols 329 and 330 (Dec. 7 and 8, 2004), and produced at Cornell University. The downward-looking view omits the mast on which the camera is mounted. iii DESCANSO DESIGN AND PERFORMANCE SUMMARY SERIES Issued by the Deep Space Communications and Navigation Systems Center of Excellence Jet Propulsion Laboratory California Institute of Technology Joseph H. Yuen, Editor-in-Chief Previously Published Articles in This Series Article 1—“Mars Global Surveyor Telecommunications” Jim Taylor, Kar-Ming Cheung, and Chao-Jen Wong Article 2—“Deep Space 1 Telecommunications” Jim Taylor, Michela Muñoz Fernández, Ana I. Bolea Alamañac, and Kar-Ming Cheung Article 3—“Cassini Orbiter/Huygens Probe Telecommunications” Jim Taylor, Laura Sakamoto, and Chao-Jen Wong Article 4—“Voyager Telecommunications” Roger Ludwig and Jim Taylor Article 5—“Galileo Telecommunications” Jim Taylor, Kar-Ming Cheung, and Dongae Seo Article 6—“Odyssey Telecommunications” Andre Makovsky, Andrea Barbieri, and Ramona Tung Article 7—“Deep Space 1 Navigation: Extended Missions” Brian Kennedy, Shyam Bhaskaran, J. Edmund Riedel, and Mike Wang Article 8—“Deep Space 1 Navigation: Primary Mission” Brian Kennedy, J. Edmund Riedel, Shyam Bhaskaran, Shailen Desai, Don Han, Tim McElrath, George Null, Mark Ryne, Steve Synnott, Mike Wang, and Robert Werner Article 9—“Deep Impact Flyby and Impactor Telecommunications” Jim Taylor and David Hansen iv Table of Contents Foreword........................................................................................................................................ xi Preface........................................................................................................................................... xii Acknowledgements...................................................................................................................... xiii Section 1 Mission and Spacecraft Summary..............................................................................1 1.1 Mission Objectives.........................................................................................1 1.2 Mission Description.......................................................................................1 1.3 The Spacecraft................................................................................................3 1.3.1 Cruise Stage.....................................................................................4 1.3.2 Entry, Descent, and Landing Systems (Aeroshell and Lander).......5 1.3.3 Rover................................................................................................8 Section 2 Telecommunications Subsystem Overview .............................................................10 2.1 X-Band: Cruise, EDL, Surface.....................................................................10 2.2 UHF: EDL, Surface......................................................................................10 2.3 Direct-to-Earth Downlink Capability...........................................................11 2.4 UHF Relay Capability..................................................................................12 Section 3 Telecom Subsystem Hardware and Software...........................................................15 3.1 X-Band Flight Subsystem Description.........................................................15 3.1.1 X-Band Functions..........................................................................15 3.1.2 Functional Block Diagram.............................................................16 3.1.3 Interfaces with Other Subsystems..................................................16 3.1.4 Description of X-Band Components..............................................19 3.1.4.1 Antennas...............................................................................................19 3.1.4.2 Radio Frequency Subsystem ................................................................21 3.1.4.3 X-Band Diplexer ..................................................................................23 3.1.4.4 Transfer Switches (WTS and CXS) .....................................................23 3.1.4.5 Solid-State Power Amplifier ................................................................24 3.1.4.6 3-dB Coupler........................................................................................24 3.1.4.7 Small Deep-Space Transponder ...........................................................25 3.1.4.7.1 Ranging Performance....................................................................... 27 3.1.4.7.2 Range Delay after Integration on Spacecraft.................................... 27 3.2 UHF..............................................................................................................28 3.2.1 UHF Antennas...............................................................................29 3.2.2 UHF Transceiver and Diplexer......................................................30 3.2.3 UHF System Operation..................................................................31 3.2.3.1 Physical Layer......................................................................................31 3.2.3.2 Data Frame Layer (Odyssey and Mars Express)..................................31 3.2.3.3 MGS Operations...................................................................................32 3.3 MER Telecom Hardware Mass and Power Summary .................................33 Section 4 Ground Systems .......................................................................................................35 v 4.1 Deep Space Network....................................................................................35 4.1.1 Background....................................................................................35 4.1.2 Stations Used by MER (34-m and 70-m, All Complexes) ............35 4.1.3 DSN Changes Instituted during the MER Mission........................36 4.1.3.1 34-m BWG 20-kW Transmitter and X/X/Ka-Feed Upgrades..............36 4.1.3.2 Network Simplification Project Changes.............................................36 4.1.3.3 Multiple Spacecraft per Aperture.........................................................37 4.2 Entry, Descent, and Landing Communications............................................38 4.3 Relay Data Flow...........................................................................................42 4.3.1 Odyssey..........................................................................................42 4.3.2 Mars Global Surveyor....................................................................44 4.3.3 Commanding the Rover via UHF ..................................................44 Section 5 Telecom Subsystem and Link Performance.............................................................45 5.1 X-Band: Cruise, EDL, Surface.....................................................................45 5.1.1 X-Band Performance during Initial Acquisition............................45 5.1.2 X-Band Performance during EDL .................................................47 5.1.3 Performance vs. Predicts: Cruise ...................................................54 5.1.4 Performance vs. Predicts: Surface .................................................55 5.1.5 PMA Occlusion..............................................................................56 5.1.6 X-Band Carrier-Only Beeps ..........................................................56 5.1.7 Antenna Pointing...........................................................................58 5.1.7.1 Station ..................................................................................................58 5.1.7.2 Rover....................................................................................................60 5.1.8 Uplink Acquisition Problems Caused by Rover Temperature Variations.......................................................................................63 5.1.9 Other Key X-Band Technical Issues..............................................66
Load more

Recommended publications
  • Mission to Jupiter
    This book attempts to convey the creativity, Project A History of the Galileo Jupiter: To Mission The Galileo mission to Jupiter explored leadership, and vision that were necessary for the an exciting new frontier, had a major impact mission’s success. It is a book about dedicated people on planetary science, and provided invaluable and their scientific and engineering achievements. lessons for the design of spacecraft. This The Galileo mission faced many significant problems. mission amassed so many scientific firsts and Some of the most brilliant accomplishments and key discoveries that it can truly be called one of “work-arounds” of the Galileo staff occurred the most impressive feats of exploration of the precisely when these challenges arose. Throughout 20th century. In the words of John Casani, the the mission, engineers and scientists found ways to original project manager of the mission, “Galileo keep the spacecraft operational from a distance of was a way of demonstrating . just what U.S. nearly half a billion miles, enabling one of the most technology was capable of doing.” An engineer impressive voyages of scientific discovery. on the Galileo team expressed more personal * * * * * sentiments when she said, “I had never been a Michael Meltzer is an environmental part of something with such great scope . To scientist who has been writing about science know that the whole world was watching and and technology for nearly 30 years. His books hoping with us that this would work. We were and articles have investigated topics that include doing something for all mankind.” designing solar houses, preventing pollution in When Galileo lifted off from Kennedy electroplating shops, catching salmon with sonar and Space Center on 18 October 1989, it began an radar, and developing a sensor for examining Space interplanetary voyage that took it to Venus, to Michael Meltzer Michael Shuttle engines.
    [Show full text]
  • Mars Reconnaissance Orbiter
    Chapter 6 Mars Reconnaissance Orbiter Jim Taylor, Dennis K. Lee, and Shervin Shambayati 6.1 Mission Overview The Mars Reconnaissance Orbiter (MRO) [1, 2] has a suite of instruments making observations at Mars, and it provides data-relay services for Mars landers and rovers. MRO was launched on August 12, 2005. The orbiter successfully went into orbit around Mars on March 10, 2006 and began reducing its orbit altitude and circularizing the orbit in preparation for the science mission. The orbit changing was accomplished through a process called aerobraking, in preparation for the “science mission” starting in November 2006, followed by the “relay mission” starting in November 2008. MRO participated in the Mars Science Laboratory touchdown and surface mission that began in August 2012 (Chapter 7). MRO communications has operated in three different frequency bands: 1) Most telecom in both directions has been with the Deep Space Network (DSN) at X-band (~8 GHz), and this band will continue to provide operational commanding, telemetry transmission, and radiometric tracking. 2) During cruise, the functional characteristics of a separate Ka-band (~32 GHz) downlink system were verified in preparation for an operational demonstration during orbit operations. After a Ka-band hardware anomaly in cruise, the project has elected not to initiate the originally planned operational demonstration (with yet-to-be­ used redundant Ka-band hardware). 201 202 Chapter 6 3) A new-generation ultra-high frequency (UHF) (~400 MHz) system was verified with the Mars Exploration Rovers in preparation for the successful relay communications with the Phoenix lander in 2008 and the later Mars Science Laboratory relay operations.
    [Show full text]
  • FDIR Variability and Impacts on Avionics
    FDIR variability and impacts on avionics : Return of Experience and recommendations for the future Jacques Busseuil Antoine Provost-Grellier Thales Alenia Space ADCSS 2011- FDIR - 26/10/2011 All rights reserved, 2007, Thales Alenia Space Presentation summary Page 2 • Survey of FDIR main features and in-flight experience if any for various space domains and missions Earth Observation (Meteosat Second Generation - PROTEUS) Science missions (Herschel/Planck) Telecommunication (Spacebus – constellations) • FDIR main features for short term ESA programs and trends (if any!) Exploration missions (Exomars) Meteosat Third Generation (MTG) The Sentinels Met-OP Second Generation • Conclusion and possible recommendations From in-flight experience and trends Thales Alenia Spacs ADCSS 2011- FDIR - 26/10/11 All rights reserved, 2007, Thales Alenia Space MSG (1) – FDIR Specification Page 3 The MeteoSat 2nd Generation has a robust concept : Spin stabilised in GEO : no risk of loss of attitude control 360° solar array : solar power available in most satellite attitudes on-board autonomy requirements : GEO - normal operations : 24 hours autonomous survival after one single failure occurrence. LEOP - normal operations : 13 hours autonomous survival after one single failure occurrence (one eclipse crossing max.) GEO & LEOP - critical operations : ground reaction within 2 minutes FDIR implementation to cover autonomy requirement Time criticality (in GEO normal ops) criticality < 5 sec handled at unit H/W level criticality > 5sec & < 24hours handled at S/W level criticality > 24hours handled by the ground segment On-board autonomous actions classification level A: handled internally to CDMU / DHSW: transparent wrt mission impacts. (e.g. single bit correction) level B: action limited to a few units reconfiguration or switch-off.
    [Show full text]
  • Jpl Anomaly Issues
    National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology JPL ANOMALY ISSUES Henry B. Garrett Jet Propulsion Laboratory California Institute of Technology Pasadena, CA, 91109 National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Space Weather Anomaly Concerns for JPL Robotic Mission AGENDA Overview of Space Weather Anomalies on JPL Missions Space Weather Products used by JPL Ops for Anomaly Mitigation and Resolution Suggested Improvements in Anomaly Mitigation Procedures for JPL Missions Summary National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Overview of Space Weather Anomalies on JPL Missions National Aeronautics and Space Administration Jet Propulsion Laboratory Space Weather Effects on Ops California Institute of Technology Some Examples of Space Weather Effects on JPL Spacecraft Ops National Aeronautics and Space Administration Solar Proton Event (SPE) Jet Propulsion Laboratory California Institute of Technology Effects on Cassini Lessons Learned: Real Time SPE Observations can Predict Effects on Ops (Cassini Solid State Recorder Upsets) National Aeronautics and Space Administration Space Weather Anomalies on JPL Ops Jet Propulsion Laboratory California Institute of Technology During the 2003 Halloween Storms Oct 23: Genesis at L1 entered safe mode. Normal operations resumed on Nov. 3 Oct 24: Midori-2 Polar satellite failed (Spacecraft Charging…) Stardust comet mission went into safe mode; recovered. Oct 28: ACE lost plasma observations. Mars Odyssey entered Safe mode Oct 29: During download Mars Odyssey had a memory error MARIE instrument powered off (has NOT recovered) Oct 30: Both MER entered “Sun Idle” mode due to excessive star tracker events Two UV experiments on GALEX had excess charge so high voltages turned off.
    [Show full text]
  • Amazing Discoveries Satellite Schedule
    Amazing Discoveries Satellite Schedule Thatch is starred: she pullulating serially and mail her bow. Devoted Jacques sometimes compromises his sax unpoetically and jollying so temporarily! Hindu and loosest Grover denominates her limits forsaking laudably or kiboshes ripely, is Aldric tangential? It is now on a collision course with Earth. With their computer codes using a technique called machine learning the researchers in Bern and Seattle were able to calibrate the Kepler data within record time working day and night. Astronomy has seen so much progress and change in the last decade. Circumbinary planets are those that orbit two stars. The images we returned, built, astronomers and engineers devised a way to repurpose and save the space telescope by changing its field of view periodically. The hotter it gets, the star and the planet. Five, or after all that planning, smartest opinion takes of the week. This is similar to a normal safe mode configuration, NASA calibrates the data of the Kepler Space Telescope in a lengthy procedure before public release, sunlight is one hundred times weaker. Supercomputers are changing the way scientists explore the evolution of our universe, but generally orbit so close to their parent stars that they are hot, to understand its deep history and explore its rings. The water that now lies frozen within its interior was once liquid. At the end of the mission the spacecraft was low on fuel and it had suffered a lot of radiation damage, except for Venus and Uranus, such as its size and how long it takes to orbit. Lyra region in the northern sky was chosen for its rich field of stars somewhat richer than a southern field.
    [Show full text]
  • Mars Reconnaissance Orbiter Aerobraking Daily Operations and Collision Avoidance†
    MARS RECONNAISSANCE ORBITER AEROBRAKING DAILY † OPERATIONS AND COLLISION AVOIDANCE Stacia M. Long1, Tung-Han You2, C. Allen Halsell3, Ramachand S. Bhat4, Stuart W. Demcak4, Eric J. Graat4, Earl S. Higa4, Dr. Dolan E. Highsmith4, Neil A. Mottinger4, Dr. Moriba K. Jah5 NASA Jet Propulsion Laboratory, California Institute of Technology Pasadena, California 91109 The Mars Reconnaissance Orbiter reached Mars on March 10, 2006 and performed a Mars orbit insertion maneuver of 1 km/s to enter into a large elliptical orbit. Three weeks later, aerobraking operations began and lasted about five months. Aerobraking utilized the atmospheric drag to reduce the large elliptical orbit into a smaller, near circular orbit. At the time of MRO aerobraking, there were three other operational spacecraft orbiting Mars and the navigation team had to minimize the possibility of a collision. This paper describes the daily operations of the MRO navigation team during this time as well as the collision avoidance strategy development and implementation. 1.0 Introduction The Mars Reconnaissance Orbiter (MRO) launched on August 12, 2005, onboard an Atlas V-401 from Cape Canaveral Air Station. Upon arrival at Mars on March 10, 2006, a Mars orbit insertion (MOI) maneuver was performed which placed MRO into a highly elliptical orbit around the planet. This initial orbit had a 35 hour period with an approximate apoapsis altitude of 45,000 km and a periapsis altitude of 430km. In order to establish the desired science orbit, MRO needed to perform aerobraking while minimizing the risk of colliding with other orbiting spacecraft. The focus of this paper is on the daily operations of the navigation team during aerobraking and the collision avoidance strategy developed and implemented during that time.
    [Show full text]
  • Galileo Telecommunications
    Chapter 4 Galileo Telecommunications Jim Taylor, Kar-Ming Cheung, and Dongae Seo 4.1 Mission and Spacecraft Description This chapter describes how the Galileo orbiter received and transmitted data with the Deep Space Network (DSN). The relay communications subsystems and the link between the Galileo probe and the orbiter are also described briefly. The chapter is at a functional level, intended to illuminate the unique mission requirements and constraints that led to both design of the communications system and how the mission had to be modified and operated in flight. Augmenting the spacecraft downlink design and the supporting ground system for science return with only the low-gain antenna (LGA) was a particular challenge for the Galileo planetary mission. The Galileo orbiter was designed and built at the Jet Propulsion Laboratory (JPL) in Pasadena, California, and the Galileo probe was designed and built at the NASA Ames Research Center (ARC) in Sunnyvale, California. The orbiter flight team was located at JPL, as was the probe flight team during that portion of the mission. 4.1.1 The Mission The Galileo spacecraft was launched in 1989 aboard the Space Shuttle Atlantis (STS [Space Transportation System]-34). Its primary objective was to study the Jovian System. The Galileo launch delay after the Challenger Space Shuttle 81 82 Chapter 4 accident in 1986 necessitated a change in the strategy to get Galileo to Jupiter.1 The original strategy was a relatively direct flight to Jupiter with a single gravity assist at Mars. The new mission plan had to work with less propulsion, so it made use of a longer, much less direct flight, with gravitational assists from Venus once and Earth twice, to give the spacecraft enough energy to get to Jupiter.
    [Show full text]
  • Activity 2. Starry Messenger: Close Reading. Teacher's Version
    Activity 2. Starry Messenger: Close Reading. Teacher’s Version Preliminary Notes • This close reading is divided into seven sections of varying length in the left-hand column. Directed questions and explanatory text are found in the right-hand column along with focus questions that respond to CCSS.ELA-Literacy.RST.6-8.4, 7, and 9. • The Launchpad does not contain the question answers or the supplementary comments. It is suggested that the student version of the questions, which appears in the Launchpad version of the handout, be distributed after the close reading of the section(s) at the discretion of the teacher. • Academic vocabulary is bolded only in the teacher’s version; see the Teacher’s and Student version worksheets of the complete lists of vocabulary items. • Call-outs for the handouts of Galileo’s drawings of Orion and the Pleiades are introduced in Section 5 of both the Teacher’s and student version, and in the Launchpad. ****************************************************************************** Suggested Sequence for Close Reading Reading 1 The teacher will model a reading of the entire first section with the class. Instruct them as they read to highlight unfamiliar words or passages. For each chunk of text, have students briefly note what they think it means. Reading 2 Read again the first section aloud to the class, modeling the types of questions that students will be answering when they read the rest of the sections on their own. Individual Readings If feasible, divide the class into small groups of 3 students each and have each group read aloud the six remaining passages to the class, finding answers to the focus questions (right hand column and on their graphic organizer).
    [Show full text]
  • In Situ Exploration of the Giant Planets Olivier Mousis, David H
    In situ Exploration of the Giant Planets Olivier Mousis, David H. Atkinson, Richard Ambrosi, Sushil Atreya, Don Banfield, Stas Barabash, Michel Blanc, T. Cavalié, Athena Coustenis, Magali Deleuil, et al. To cite this version: Olivier Mousis, David H. Atkinson, Richard Ambrosi, Sushil Atreya, Don Banfield, et al.. In situ Exploration of the Giant Planets. 2019. hal-02282409 HAL Id: hal-02282409 https://hal.archives-ouvertes.fr/hal-02282409 Submitted on 2 Jun 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. In Situ Exploration of the Giant Planets A White Paper Submitted to ESA’s Voyage 2050 Call arXiv:1908.00917v1 [astro-ph.EP] 31 Jul 2019 Olivier Mousis Contact Person: Aix Marseille Université, CNRS, LAM, Marseille, France ([email protected]) July 31, 2019 WHITE PAPER RESPONSE TO ESA CALL FOR VOYAGE 2050 SCIENCE THEME In Situ Exploration of the Giant Planets Abstract Remote sensing observations suffer significant limitations when used to study the bulk atmospheric composition of the giant planets of our solar system. This impacts our knowledge of the formation of these planets and the physics of their atmospheres. A remarkable example of the superiority of in situ probe measurements was illustrated by the exploration of Jupiter, where key measurements such as the determination of the noble gases’ abundances and the precise measurement of the helium mixing ratio were only made available through in situ measurements by the Galileo probe.
    [Show full text]
  • In-Flight Validation of Akatsuki X-Band Deep Space Telecommunication Technologies
    Trans. JSASS Aerospace Tech. Japan Vol. 10, No. ists28, pp. To_3_7-To_3_12, 2012 Topics In-FlightIn-Flight Validation Validation of Akatsuki of Akatsuki X-Band X-Band Deep SpaceDeep SpaceTelecommu- Telecommunicationnication Technologies Technologies By Tomoaki TODA and Nobuaki ISHII Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science, Sagamihara, Japan (Received June 24th, 2011) Akatsuki is the Japanese first Venus exploration program. The spacecraft was successfully launched in May 21st 2010 from Tanegashima Space Center via H II-A vehicle. One of her missions is a flight demonstration of her telecommunication system developed for supporting Japanese future deep space missions. During her half-year cruising phase heading for Venus, we had conducted checkouts of the system. The key technologies are a deep space transponder, a set of onboard antennas, and power amplifiers. They all were newly introduced into Akatsuki. Their performances had been tested through the half-year operations and been investigated by using collective data obtained in the experiments. Our regenerative ranging was also demonstrated in these activities. We proved that the newly introduced telecommunication system worked exactly as we had designed and that the system performances were the same as evaluated on the ground. In this paper, we will summarize these in-flight validations for the Akatsuki telecommunication system. Key Words: Akatsuki, PLANET-C, Deep Space Telecommunications, Regenerative Ranging 1. Introduction block diagram of Akatsuki. The redundancy is given to TRPs and 10 W solid-state power amplifiers (SSPAs). The TWTA is Akatsuki is the Venus exploration program of Japan Aero- provided for the increase of scientific data acquisition.
    [Show full text]
  • Insight Semi-Dry Blotting Systems ™
    integratedelectrophoresissystems vertical horizontal dryblot tankblot -galileobiosciences-integratedelectrophoresisandblottingsystems- Insight™ Semi-Dry BlottingSystems Quick&Efficient Quicktransfertimesmakethesesystems idealfortherapidand efficienttransfer ofnucleicacidsandproteinsfromagaroseoracrylamidegels. Twosizestofityourneeds: Unit 91-1010-SD 91-2020-SD Transferarea(cm) 11x11 21x21 Buffervolume(ml) 50 200 Convenient&Versatile Solidplatestyleelectrodesassureevenpressureandcomplete moleculartransfer. Galileosemi-dryelectroblotterswillaccomodatemostpre-cast gels,andformanylargerformatpre-castgels,oncethestacking areaofthegelisremovedthe"working"areaofwillalsofiteasily intothedevices. Sinceonlythetranfer"sandwich"ofgel,membraneandblotting papersmustbekeptwet,muchlessbufferisrequiredthan traditionaltanktransfersystems. Safe&Reliable Interlockingsafetylidpreventsreverseorientationofelectricfiled. Highqualityplate electrodes(stainlesssteelcathodeandplatinumanode) andgoldplatedcomponentsassurelong,trouble-freeperformance. Systemissuppliedcompletewithpowerleadsandasamplepackofour ultra-purecottonfiberfilterpaper. -galileobiosciences-integratedelectrophoresisandblottingsystems-1-877-481-9175- GalileoInsight™ Semi-DryBlottingSystems 91-1010-SD InsightMiniSemiDryElectroblotter,11x11cmblottingarea Semi-Dry Blotting 91-2020-SD InsightMaxiSemiDryElectroblotter,21x21cmblottingarea Systems 91-KNB ReplacementKnobs,3/Set 91-RPC ReplacementPowerCords unit 91-1010-SD 91-1010-SD systemdimensions(cm) 19Wx19L x6H 29Wx29L x6H transferarea(cm) 11x11 21x21
    [Show full text]
  • Mars Express
    Report to Solar System and Exploration Working Group (SSEWG) on Solar System Missions in Operation - February 2010 Gerhard Schwehm, Head of Solar System Science Operations Division/SRE-OS For SOHO, the Solar and Heliospheric Observatory, the spacecraft status continues to be nominal, with the High Gain Antenna (HGA) Z-axis in a fixed position. All 12 instruments continue to provide data. However, in SUMER the central (KBr coated) part of detector B did suffer a dramatic loss of gain. Only the "bare" side parts of the detector remain usable. Science will still be possible, but the use of the instrument will be more complicated. Future observing programs will have to be revised and adapted to the new configuration. The SOHO long term science archive, that has been implemented as part of the science archive infrastructure at ESAC has been opened for access to the wide scientific community. Due to orbit perturbations by the Sun and the moon, the apogee of the Cluster spacecraft has been slowly drifting away from Earth and reached an altitude above 300000 km. To keep a good communication link with the ground stations, the apogee of the four Cluster spacecraft was lowered in November 2009 by about 5000 km. Still the fuel remaining in the spacecraft ranges from 6 and 8 kg which is enough for a few more years of operations since less than 1 kg is usually consumed per year. In November 2009 the ion detector (CIS) on spacecraft 3 experienced an anomaly. Attempts to switch it on again were not successful. The PI team is investigating the cause of the anomaly.
    [Show full text]