Game changing: NASA's space launch system and science mission design

The National Aeronautics and Space Administration s (NASA) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center (MSFC), is charged with delivering a new capability for human and scientific exploration beyond Earth orbit (BEO). The SLS may also provide backup crew and cargo services to the International Space Station, where astronauts have been training for long-duration voyages to destinations such as asteroids and Mars. For context, the SLS will be larger than the Saturn V, providing 10 percent more thrust at liftoff in its initial 70 metric ton (t) configuration and 20 percent more in its evolved 130-t configuration. The SLS Program knows that affordability is the key to sustainability. This paper will provide an overview of its operations strategy, which includes initiatives to reduce both development and fixed costs by using existing hardware and infrastructure assets to meet a first launch by 2017 within the projected budget. It also has a long-range plan to keep the budget flat using competitively selected advanced technologies that offer appropriate return on investment. To arrive at the launch vehicle concept, the SLS Program conducted internal engineering and business studies that have been externally validated by industry and reviewed by independent assessment panels. A series of design reference missions has informed the SLS operations concept, including launching the Orion Multi-Purpose Crew Vehicle (MPCV) on an autonomous demonstration mission in a lunar flyby scenario in 2017, and the first flight of a crew on Orion for a lunar flyby in 2021. Additional concepts address the processing of very large payloads, using a series of modular fairings and adapters to flexibly configure the rocket for the mission. This paper will describe how the SLS, Orion, and Ground Systems Development and Operations (GSDO) programs are working together to create streamlined, affordable operations for sustainable exploration for decades to come.

The National Aeronautics and Space Administration (NASA) is developing new capabilities for human and scientific exploration beyond Earth's orbit. This effort includes the Space Shuttle derived Space Launch System (SLS), the Multi-Purpose Crew Vehicle (MPCV) and the Ground Systems Development and Operations (GSDO). There are several requirements and Technical Performance Measures (TPMs) that have been levied by the Exploration Systems Development (ESD) upon the SLS, MPCV, and GSDO Programs including an integrated Launch Availability (LA) TPM. The LA TPM is used to drive into the SLS, Orion and GSDO designs a high confidence of successfully launching exploration missions that have narrow Earth departure windows. The LA TPM takes into consideration the reliability of the overall system (SLS, Orion and GSDO), natural environments, likelihood of a failure, and the time required to recover from an anomaly. A challenge with the LA TPM is the interrelationships between SLS, Orion, GSDO and the natural environments during launch countdown and launch delays that makes it impossible to develop an analytical solution for calculating the integrated launch probability. This paper provides an overview of how Discrete Event Simulation (DES) modeling was used to develop the LA TPM, how it was allocated down to the individual programs, and how the LA analysis is being used to inform and drive the SLS, Orion, and GSDO designs to ensure adequate launch availability for future human exploration.

Science on the lunar surface facilitated by low latency telerobotics from a Lunar Orbital Platform - Gateway

Aerospace - Rocket. The Gallery. Nasa's Space Launch System

The NASA Space Launch System (SLS) Block 1 configuration is progressing toward a 2021 first flight, which will launch an uncrewed Orion capsule to the Moon. The SLS' Core Stage has finished its Green Run, full duration test at NASA Stennis Space Center. In this report, the SLS development status and its launch capabilities are discussed, and the new optimized Exploration Upper Stage, currently in development, which will optimize the SLS Core and Booster Stages, is presented. Ten Beyond Earth Orbit (BEO) missions, enabled or enhanced by the SLS, are also reviewed.

A new vector magnetograph is being developed at NASA's Marshall Space Flight Center (MSFC) to measure polarization from active regions on the Sun. This paper will describe the polarization characteristics of the elements that make up the MSFC EXperimental Vector Magnetograph (EXVM) polarimeter. Based on those characteristics, the systematic errors associated with this polarimeter will be modeled and the polarization resolution that could be achieved in a space-based (or balloon-based) instrument will be discussed.

Exciting and robust human and robotic exploration missions will be enabled by the NASA Space Launch System (SLS). The SLS's capabilities for launching heavy payloads with large diameters (up to 10 meters) will enable a variety of science rich missions including Mars and outer planet missions; including Human missions utilizing the Orion Crew Vehicle. Missions to cislunar destinations will serve as proving grounds for later Crewed Mars Missions in the 2030s. In this report an outline is given of the capabilities of the SLS, strategies for exploration missions are presented, and descriptions of SLS based payload elements are given. The SLS program is making progress toward delivering a new capability for Beyond Earth Orbit exploration.

The Video Guidance Sensor (VGS) has been developed by NASA's Marshall Space Flight Center (MSFC) to provide the capability for a spacecraft to find and track a target vehicle and determine the relative positions and attitudes between the sensor and the target. The sensor uses laser diodes to illuminate the target, a CCD-based camera to sense the target, and a frame-grabber and processor to convert the video information into relative range, azimuth, elevation, roll, pitch, and yaw. The sensor was first built in 1988 and used in successful automated docking experiments using the air-bearing spacecraft simulator in MSFC's Flight Robotics Laboratory. Since then, many changes and improvements have been made, based on the results of testing. In addition to the use of this system for space vehicles, it has been adapted for commercial application. The current design is being built as a prototype to prepare for flight testing on the Space Shuttle. Some of the changes from the original system were designed to improve the noise rejection of the system. Other changes were made to improve the overall range of operation of the system, and still other changes improved the bandwidth of the system. The current VGS is designed to operate from 110 meters down to 0.5 meters and output the relative position and attitude data at 5 Hz. The system will be able to operate under any orbital lighting conditions from full solar illumination to complete darkness. The VGS is also designed to be used with more than one target and sensor to allow for redundant configurations. This new prototype should be completed and undergoing open- and closed-loop testing after March 1995.

<div class="htmlview paragraph">Testing of the International Space Station (ISS) U.S. Laboratory baseline configuration of the Atmosphere Revitalization Subsystem (ARS) by NASA's Marshall Space Flight Center (MSFC) has been conducted as part of the Environmental Control and Life Support System (ECLSS) design and development program. This testing addressed specific questions with respect to the control and performance of the baseline ARS subassemblies in the ISS U.S. Laboratory configuration. The test used pressurized oxygen injection, a mass spectrometric major constituent analyzer (MCA), a four-bed molecular sieve carbon dioxide removal assembly (CDRA), and a trace contaminant control subassembly (TCCS) to maintain the atmospheric composition in a sealed chamber within ISS specifications. Human metabolic processes for a crew of four are simulated according to projected ISS mission timelines.</div> <div class="htmlview paragraph">The Integrated ARS Test (IART) builds upon previous integrated ECLSS testing conducted at MSFC between 1987 and 1992. The IART is designed to address ARS control and performance issues that are peculiar to the ISS. These issues resulted from the ISS ECLSS configuration development, design requirement changes since 1992, and the increased maturity of each ARS subassembly's design. IART test objectives, facility design, pretest analyses, test and control requirements, and test results are presented.</div>

Properly planned and executed metrology crosschecks at low to mid system test levels can provide up to the same degree of end item performance insurance protection that a top-level end-to-end test can, at a small fraction of the cost, and in a much more timely manner in terms of identifying and correcting problems. This philosophy has been put into rigorous practice on the optics fabrication activity being performed by Hughes Danbury Optical Systems, under contract to TRW, on the Advanced X-ray Astrophysics Facility (AXAF) program being managed by NASA's Marshall Space Flight Center. The process to date, while for the most part having provided confidence that the primary calibrations and tests are correct, has also identified several significant but subtle errors that were corrected. The focus of the paper is on the process itself as an optical quality insurance tool, with examples from AXAF described.

This paper describes the development and testing of the initial version of a common space systems ontology (CoSSO) for use by the Advanced Concepts Office (ACO) at NASA's Marshall Space Flight Center. The ontology provides a shared conceptualization of concepts of interest to the ACO for modeling aerospace systems concepts in a pre-phase A context to aid with the transition to a more model-based paradigm. The ontological concepts and relations, as well as the anticipated use cases, were developed through interactions with the relevant subject matter experts at the ACO and implemented in the Ontological Modeling Language (OML). The ontology builds on the Basic Formal Ontology (BFO) and the Common Core Ontologies (CCO). While most of the ontology is still in the initial stages, an Environmental Control and Life Support System (ECLSS) ontology is being built on top of the main CoSSO and heavily developed as a proof of concept. The ECLSS ontology is designed with different use cases in mind, namely predicting and diagnosing errors in ECLS systems on long-duration missions, with a focus on the Four-Bed CO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> carbon dioxide scrubber currently on board the ISS. The ECLSS ontology is being developed in a similar manner to the CoSSO, and designed to be compatible with it. The current state of both ontologies is presented and discussed, along with plans for future development and testing.

NASA's Marshall Space Flight Center, in collaboration with Blue Line Engineering of Colorado Springs, Colorado, is developing a Segment Alignment Maintenance System (SAMS) for McDonald Observatory's Hobby-Eberly Telescope (HET). The SAMS shall sense motions of the 91 primary mirror segments and send corrections to HET's primary mirror controller as the mirror segments misalign due to thermo-elastic deformations of the mirror support structure. The SAMS consists of inductive edge sensors. All measurements are sent to the SAMS computer where mirror motion corrections are calculated. In October 2000, a prototype SAMS was installed on a seven-segment cluster of the HET. Subsequent testing has shown that the SAMS concept and architecture are a viable practical approach to maintaining HET's primary mirror figure, or the figure of any large segmented telescope. This paper gives a functional description of the SAMS sub-array components and presents test data to characterize the performance of the sub-array SAMS.

Many different techniques have been used in attempts to minimize defects in single crystal semiconductors. This study examines semiconductors grown in the presence of a rotating magnetic field (RMF). The RMF method is commonly used in metallurgy to stir an electrically conducting liquid during the casting process which can reduce the effects of buoyancy driven convection and enhance the mass transfer process. The variation of heat and mass transfer processes by RMF can be controlled by selecting a specific frequency and strength of the magnetic field. Both numerical modeling and space-based crystal growth experiments using RMF indicate that the application of RMF to solidification of semiconductors will dramatically minimize defects and inclusions.A ground based program in the Microgravity Research Division at NASA's Marshall Space Flight Center has been studying the effects of RMF on various semiconductor compounds grown by the traveling heater method (THM).

The Constellation X-ray Mission is the next major x-ray- astronomy mission in the NASA Space Science road map. As a follow-on to the Chandra X-ray Observatory--nee, the Advanced X-ray Astrophysics Facility--Constellation X will provide high-throughput, high-resolution spectroscopy to probe the gravitational field, kinematics, temperature, density, composition and ionization state of cosmic sources. The Constellation-X observatory system comprises four separate satellites, each with one large Spectroscopy X-ray Telescope (SXT, with a pixelated microcalorimeter and a reflection-grating-CCD spectrometer) and three smaller Hard X-ray Telescopes (HXTs, with pixelated hard-x-ray detectors). Essential to the success of Constellation X is the development of large (1.6-m-diameter), lightweight optics for the SXT mirror assembly. With the Smithsonian Astrophysical Observatory, teams led by NASA's Marshall Space Flight Center, by NASA's Goddard Space Flight Center, and by Italy's Osservatorio Astronomico di Brera are currently developing competing mirror techniques for lightweight SXT optics, toward achieving the required system-level half-power diameter--better than 15 arcsec.

The Night Projects Directorate at NASA's Marshall Space Flight Center is developing a new planning and scheduling environment and a new scheduling algorithm to enable a paradigm shift in planning and scheduling concepts. Over the past 33 years Marshall has developed and evolved a paradigm for generating payload timelines for Skylab, Spacelab, various other Shuttle payloads, and the International Space Station. The current paradigm starts by collecting the requirements, called ?ask models, from the scientists and technologists for the tasks that are to be scheduled. Because of shortcomings in the current modeling schema, some requirements are entered as notes. Next, a cadre with knowledge of vehicle and hardware modifies these models to encompass and be compatible with the hardware model; again, notes are added when the modeling schema does not provide a better way to represent the requirements. Finally, the models are modified to be compatible with the scheduling engine. Then the models are submitted to the scheduling engine for automatic scheduling or, when requirements are expressed in notes, the timeline is built manually. A future paradigm would provide a scheduling engine that accepts separate science models and hardware models. The modeling schema would have the capability to represent all the requirements without resorting to notes. Furthermore, the scheduling engine would not require that the models be modified to account for the capabilities (limitations) of the scheduling engine. The enabling technology under development at Marshall has three major components: (1) A new modeling schema allows expressing all the requirements of the tasks without resorting to notes or awkward contrivances. The chosen modeling schema is both maximally expressive and easy to use. It utilizes graphical methods to show hierarchies of task constraints and networks of temporal relationships. (2) A new scheduling algorithm automatically schedules the models without the intervention of a scheduling expert. The algorithm is tuned for the constraint hierarchies and the complex temporal relationships provided by the modeling schema. It has an extensive search algorithm that can exploit timing flexibilities and constraint and relationship options. (3) An innovative architecture allows multiple remote users to simultaneously model science and technology requirements and other users to model vehicle and hardware characteristics. The architecture allows the remote users to submit scheduling requests directly to the scheduling engine and immediately see the results. These three components are integrated so that science and technology experts with no knowledge of the vehicle or hardware subsystems and no knowledge of the internal workings of the scheduling engine have the ability to build and submit scheduling requests and see the results. The immediate feedback will hone the users' modeling skills and ultimately enable them to produce the desired timeline. This paper summarizes the three components of the enabling technology and describes how this technology would make a new paradigm possible.