James Webb Space Telescope XML Database: From the Beginning to Today

The James Webb Space Telescope (JWST) Project has been defining, developing, and exercising the use of a common eXtensible Markup Language (XML) for the command and telemetry (C&T) database structure. JWST is the first large NASA space mission to use XML for databases. The JWST project started developing the concepts for the C&T database in 2002. The database will need to last at least 20 years since it will be used beginning with flight software development, continuing through Observatory integration and test (I&T) and through operations. Also, a database tool kit has been provided to the 18 various flight software development laboratories located in the United States, Europe, and Canada that allows the local users to create their own databases. Recently the JWST Project has been working with the Jet Propulsion Laboratory (JPL) and Object Management Group (OMG) XML Telemetry and Command Exchange (XTCE) personnel to provide all the information needed by JWST and JPL for exchanging database information using a XML standard structure. The lack of standardization requires custom ingest scripts for each ground system segment, increasing the cost of the total system. Providing a non-proprietary standard of the telemetry and command database definition formation will allow dissimilar systems to communicate without the need for expensive mission specific database tools and testing of the systems after the database translation. The various ground system components that would benefit from a standardized database are the telemetry and command systems, archives, simulators, and trending tools. JWST has exchanged the XML database with the Eclipse, EPOCH, ASIST ground systems, Portable spacecraft simulator (PSS), a front-end system, and Integrated Trending and Plotting System (ITPS) successfully. This paper will discuss how JWST decided to use XML, the barriers to a new concept, experiences utilizing the XML structure, exchanging databases with other users, and issues that have been experienced in creating databases for the C&T system

The Earth Based Ground Stations Element of the Lunar Program

The Lunar Architecture Team (LAT) is responsible for developing a concept for building and supporting a lunar outpost with several exploration capabilities such as rovers, colonization, and observatories. The lunar outpost is planned to be located at the Moon's South Pole. The LAT Communications and Navigation Team (C&N) is responsible for defining the network infrastructure to support the lunar outpost. The following elements are needed to support lunar outpost activities: A Lunar surface network based on industry standard wireless 802.xx protocols, relay satellites positioned 180 degrees apart to provide South Pole coverage for the half of the lunar 28-day orbit that is obscured from Earth view, earth-based ground stations deployed at geographical locations 120 degrees apart. This paper will focus on the Earth ground stations of the lunar architecture. Two types of ground station networks are discussed. One provides Direct to Earth (DTE) support to lunar users using Kaband 23/26Giga-Hertz (GHz) communication frequencies. The second supports the Lunar Relay Satellite (LRS) that will be using Ka-band 40/37GHz (Q-band). This paper will discuss strategies to provide a robust operational network in support of various lunar missions and trades of building new antennas at non-NASA facilities, to improve coverage and provide site diversification for handling rain attenuation

JWST Ground Segment and Operations Integration and Testing

This viewgraph presentation reviews the operations integration and testing associated with the JWST ground network

Standardization of XML Database Exchanges and the James Webb Space Telescope Experience

Personnel from the National Aeronautics and Space Administration (NASA) James Webb Space Telescope (JWST) Project have been working with various standard communities such the Object Management Group (OMG) and the Consultative Committee for Space Data Systems (CCSDS) to assist in the definition of a common extensible Markup Language (XML) for database exchange format. The CCSDS and OMG standards are intended for the exchange of core command and telemetry information, not for all database information needed to exercise a NASA space mission. The mission-specific database, containing all the information needed for a space mission, is translated from/to the standard using a translator. The standard is meant to provide a system that encompasses 90% of the information needed for command and telemetry processing. This paper will discuss standardization of the XML database exchange format, tools used, and the JWST experience, as well as future work with XML standard groups both commercial and government

James Webb Space Telescope - L2 Communications for Science Data Processing

JWST is the first NASA mission at the second Lagrange point (L2) to identify the need for data rates higher than 10 megabits per second (Mbps). JWST will produce approximately 235 Gigabits of science data every day that will be downlinked to the Deep Space Network (DSN). To get the data rates desired required moving away from X-band frequencies to Ka-band frequencies. To accomplish this transition, the DSN is upgrading its infrastructure. This new range of frequencies are becoming the new standard for high data rate science missions at L2. With the new frequency range, the issues of alternatives antenna deployment, off nominal scenarios, NASA implementation of the Ka-band 26 GHz, and navigation requirements will be discussed in this paper. JWST is also using Consultative Committee for Space Data Systems (CCSDS) standard process for reliable file transfer using CCSDS File Delivery Protocol (CFDP). For JWST the use of the CFDP protocol provides level zero processing at the DSN site. This paper will address NASA implementations of Ground Stations in support of Ka-band 26 GHz and lesson learned from implementing a file base (CFDP) protocol operational system

James Webb Space Telescope - Applying Lessons Learned to I&T

The James Webb Space Telescope (JWST) is part of a new generation of spacecraft acquiring large data volumes from remote regions in space. To support a mission such as the JWST, it is imperative that lessons learned from the development of previous missions such as the Hubble Space Telescope and the Earth Observing System mission set be applied throughout the development and operational lifecycles. One example of a key lesson that should be applied is that core components, such as the command and telemetry system and the project database, should be developed early, used throughout development and testing, and evolved into the operational system. The purpose of applying lessons learned is to reap benefits in programmatic or technical parameters such as risk reduction, end product quality, cost efficiency, and schedule optimization. In the cited example, the early development and use of the operational command and telemetry system as well as the establishment of the intended operational database will allow these components to be used by the developers of various spacecraft components such that development, testing, and operations will all use the same core components. This will reduce risk through the elimination of transitions between development and operational components and improve end product quality by extending the verification of those components through continual use. This paper will discuss key lessons learned that have been or are being applied to the JWST Ground Segment integration and test program

The Building Blocks for JWST I and T (Integrations and Test) to Operations - From Simulator to Flight Units

The James Webb Space Telescope (JWST) Project has an extended integration and test (I&T) phase due to long procurement and development times of various components as well as recent launch delays. The JWST Ground Segment and Operations group has developed a roadmap of the various ground and flight elements and their use in the various JWST I&T test programs. The JWST Project s building block approach to the eventual operational systems, while not new, is complex and challenging; a large-scale mission like JWST involves international partners, many vendors across the United States, and competing needs for the same systems. One of the challenges is resource balancing so simulators and flight products for various elements congeal into integrated systems used for I&T and flight operations activities. This building block approach to an incremental buildup provides for early problem identification with simulators and exercises the flight operations systems, products, and interfaces during the JWST I&T test programs. The JWST Project has completed some early I&T with the simulators, engineering models and some components of the operational ground system. The JWST Project is testing the various flight units as they are delivered and will continue to do so for the entire flight and operational system. The JWST Project has already and will continue to reap the value of the building block approach on the road to launch and flight operations

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

James Webb Space Telescope: Supporting Multiple Ground System Transitions in One Year

Ideas, requirements, and concepts developed during the very early phases of the mission design often conflict with the reality of a situation once the prime contractors are awarded. This happened for the James Webb Space Telescope (JWST) as well. The high level requirement of a common real-time ground system for both the Integration and Test (I&T), as well as the Operation phase of the mission is meant to reduce the cost and time needed later in the mission development for re-certification of databases, command and control systems, scripts, display pages, etc. In the case of JWST, the early Phase A flight software development needed a real-time ground system and database prior to the spacecraft prime contractor being selected. To compound the situation, the very low level requirements for the real-time ground system were not well defined. These two situations caused the initial real-time ground system to be switched out for a system that was previously used by the Bight software development team. To meet the high-!evel requirement, a third ground system was selected based on the prime spacecraft contractor needs and JWST Project decisions. The JWST ground system team has responded to each of these changes successfully. The lessons learned from each transition have not only made each transition smoother, but have also resolved issues earlier in the mission development than what would normally occur

XML: James Webb Space Telescope Database Issues, Lessons, and Status

This paper will present the current concept using extensible Markup Language (XML) as the underlying structure for the James Webb Space Telescope (JWST) database. The purpose of using XML is to provide a JWST database, independent of any portion of the ground system, yet still compatible with the various systems using a variety of different structures. The testing of the JWST Flight Software (FSW) started in 2002, yet the launch is scheduled for 2011 with a planned 5-year mission and a 5-year follow on option. The initial database and ground system elements, including the commands, telemetry, and ground system tools will be used for 19 years, plus post mission activities. During the Integration and Test (I&T) phases of the JWST development, 24 distinct laboratories, each geographically dispersed, will have local database tools with an XML database. Each of these laboratories database tools will be used for the exporting and importing of data both locally and to a central database system, inputting data to the database certification process, and providing various reports. A centralized certified database repository will be maintained by the Space Telescope Science Institute (STScI), in Baltimore, Maryland, USA. One of the challenges for the database is to be flexible enough to allow for the upgrade, addition or changing of individual items without effecting the entire ground system. Also, using XML should allow for the altering of the import and export formats needed by the various elements, tracking the verification/validation of each database item, allow many organizations to provide database inputs, and the merging of the many existing database processes into one central database structure throughout the JWST program. Many National Aeronautics and Space Administration (NASA) projects have attempted to take advantage of open source and commercial technology. Often this causes a greater reliance on the use of Commercial-Off-The-Shelf (COTS), which is often limiting. In our review of the database requirements and the COTS software available, only very expensive COTS software will meet 90% of requirements. Even with the high projected initial cost of COTS, the development and support for custom code over the 19-year mission period was forecasted to be higher than the total licensing costs. A group did look at reusing existing database tools and formats. If the JWST database was already in a mature state, the reuse made sense, but with the database still needing to handing the addition of different types of command and telemetry structures, defining new spacecraft systems, accept input and export to systems which has not been defined yet, XML provided the flexibility desired. It remains to be determined whether the XML database will reduce the over all cost for the JWST mission