Two out of three missions to the red planet have failed. One reason there have been so many losses is that there have been so many attempts. “Mars is a favorite target,” says Dr. Firouz Naderi, manager of the Mars Program Office at the Jet Propulsion Laboratory. To get there, Spirit and Opportunity, the two Mars Exploration Rovers launched this past June and July, will have to fly through about 483 million kilometers (300 million miles) of deep space and target a very precise spot to land. Adjustments to their flight paths can be made along the way, but a small trajectory error can result in a big detour and or even missing the planet completely.
The space environment isn’t friendly. Hazards range from what engineers call “single event upsets,” as when a stray particle of energy passes through a chip in the spacecraft’s computer causing a glitch and possibly corrupting data, to massive solar flares, such as the ones that occurred this fall, that can damage or even destroy spacecraft electronics.
The road to the launch pad is nearly as daunting as the journey to Mars. Even before the trip to Mars can begin, a craft must be built that not only can make the arduous trip but can complete its science mission once it arrives. Nothing less than exceptional technology and planning is required.
If getting to Mars is hard, landing there is even harder. “One colleague describes the entry, descent and landing as six minutes of terror,” says Naderi. So, the challenge of entry, descent and landing is how to get something that massive traveling at 19,300 kilometers per hour (12,000 miles per hour) slowed down in six minutes to have a chance of survival.”
The risks are also great. “We do everything humanly possible and try to avoid human mistakes,” says Naderi. “That’s why we check, double check, test and test again and then have independent eyes check everything again. Humans, even very smart humans, are fallible particularly when many thousands of parameters are involved. But even if you have done the best engineering possible, you still don’t know what Mars has in store for you on the day your arrive. Mars can get you.”
Each step in expanding human presence beyond low Earth orbit relies on the readiness of new capabilities and technologies. As no single agency has the resources to develop all those critical capabilities, appropriately leveraging global investments in technology development and demonstration is important.
The International Space Exploration Coordination Group (ISECG) has released the third iteration of its Global Exploration Roadmap with some important changes including the moon as an important step and the increased role of the private sector. The Global Exploration Roadmap is the product of 15 national space agencies which includes the Canadian Space Agency.
Space agencies have identified a list of critical technologies related to the missions in the Global Exploration Roadmap that are currently not available or need to be developed or matured. These technologies are considered technology “pulls” and can be mapped to corresponding agency technology development activities. By mapping critical technology needs to agency technology development activities, gaps can be identified.
Detailed gap assessments of selected critical technologies have shown that:
Liquid Oxygen/Methane propulsion technologies can make use of in-situ propellant production, lead to improved performance, and leverage fluid commonality. Technology gaps that need to be addressed include throttleable engines, thrusters with integrated cryogenic feed systems, long-duration reliable cryogenic refrigeration systems, and high performance pressurization systems that improve storage density and reduce mass.
Dust mitigation technologies are a key enabling factor to perform extended duration lunar surface missions. While viable technology solutions have been identified by experts, there is a need for the maturation of related technologies to support both lunar and Mars missions. No single technology completely solves the challenges of dust, but rather a suite of technologies will be required to address them.
Autonomous systems enable the crew to conduct operations under nominal and off-nominal conditions independent of assistance from Earth-based support. Advances in electronics, computing architectures and software that enable autonomous systems to interact with humans are needed and can be leveraged from commercial markets to support maturation of needed capabilities.
Tele-robotic operations with time delay can make human-in-the-loop commanding and monitoring of robots at remote distances less effective. For safety and efficiency with time delays greater than five seconds, it is recommended that robots be operated as autonomously as possible. Terrestrial applications in this area are well advanced but on-orbit applications need to be matured.
Technology Area (TA) roadmaps
The promising new technology candidates that will help NASA achieve its extraordinary missions are identified in the 2015 NASA Technology Roadmaps. The 2015 NASA Technology Roadmaps are comprised of 16 sections: Crosscutting Technologies, and Index; and 15 distinct Technology Area (TA) roadmaps.
TA 1: Launch Propulsion Systems
These addresses technologies that enhance existing solid or liquid propulsion technologies or their related ancillary systems. The overall goals of TA 1 technology candidates are to make access to space—specifically low-Earth orbit (LEO)—more reliable, routine, and cost effective.
TA 2: In-Space Propulsion Technologies
These addresses the development of higher-power electric propulsion, nuclear thermal propulsion, and cryogenic chemical propulsion. Improvements derived from technology candidates within this TA will decrease transit times, increase payload mass, provide safer spacecraft, and decrease costs.
TA 3: Space Power and Energy Storage
These addresses technology developments to produce power systems with significant mass and volume reductions, increased efficiency, and capability for operation across a broad temperature range and in intense radiation environments. Technology advances in space power and energy storage offer significant benefits to spacecraft, launch vehicles, landers, rovers, spacesuits, tools, habitats, communication networks, and anything that requires power and energy.
TA 4: Robotics and Autonomous Systems
These will play a key role in the surveying, observation, extraction, and close examination of planetary surfaces, their natural phenomena, their terrain composition, and their resources. For human exploration, the goal is to leverage robots in all phases: as precursor explorers that precede crewed missions, as crew helpers in space, and as caretakers of assets left behind.
Remote Interaction is assigned a high priority because it is defined as providing control and communication methods that enable humans to remotely operate otherwise autonomous systems and robots. Supervisory control incorporates techniques necessary for controlling robotic
behaviors using higher-level goals instead of low-level commands, thus requiring robots to have semiautonomous or autonomous behaviors. This technology will support the design of gamechanging science and exploration missions, such as new robotic missions at remote locations and simultaneous robotic missions with reduced human oversight. Remote Interaction also includes technology for enabling manual control of remote systems and for enabling operators to monitor system status, assess task progress, perceive the remote environment, and make informed operational decisions, such as tactical plans.
TA 5: Communications, Navigation, and Orbital Debris Tracking and Characterization.
NASA’s space communications and navigation infrastructure provides the means of transferring commands, spacecraft telemetry, mission data, and voice for human exploration missions, while maintaining accurate timing and providing navigation support. Advancements in communications and navigation technologies will allow future missions to implement new and more capable science instruments, greatly enhance human missions beyond Earth orbit, and enable entirely new mission concepts.
TA 6: Human Health, Life Support, and Habitation Systems
These focuses on developing technologies that enable long-duration, deep-space human exploration with minimal resupply consumables and increased independence from Earth, within permissible space radiation exposure limits. For future crewed missions beyond low-Earth orbit (LEO) and into the solar system, regular resupply of consumables and emergency or quick-return options will not be feasible, and spacecraft will experience a more challenging radiation environment in deep space than in LEO.
TA 7: Human Exploration Destination Systems
TA 7 Systems covers the broad range of technology candidates associated with enabling successful human activities in space, from missions operations to in-situ resource utilization. All TA 7 goals relate to sustaining human presence in space, which will require existing systems and vehicles to become more independent, incorporate intelligent autonomous operations, and take advantage of the local resources.
TA 8: Science Instruments, Observatories, and Sensor Systems.
The technologies for TA 8 allow information to be gathered about Earth’s atmosphere, space, and other planets. TA 8 technologies are organized into remote sensing instruments and sensors, observatories, and in-situ instruments and sensors. These technologies are necessary to collect and process scientific data, to provide crucial knowledge to enable robotic missions such as remote surveys of Martian geology to identify optimal landing sites.
TA 9: Entry, Descent, and Landing technologies
These support NASA’s goal to send humans to the surface of Mars. The key performance characteristics that EDL technology developments will target are landed mass, reliability, cost, landing site elevation, and landing accuracy.
Terrain-Relative Sensing and Characterization This technology would produce “high-rate, high-accuracy measurements for
algorithms that enable safe precision landing near areas of high scientific interest or predeployed assets.” It impacts multiple missions in multiple mission areas, both human and robotic.
Autonomous targeting: By improving the ability of vehicles to assess and characterize the terrain they are facing for landing and exploration, this technology would enable the next step of autonomous targeting, which could be critical when interplanetary distances make remote guidance difficult or
impossible. Even if a vehicle is piloted for a human mission, this technology could be critical to help assure a safe landing.
TA 10: Nanotechnology.
Areas where nanotechnologies have the greatest potential to impact NASA mission needs include: reduced vehicle mass; improved functionality and durability; enhanced power generation and energy storage; increased propulsion performance; improved astronaut health management; and higher-efficiency advanced electronics and sensors.
TA 11: Modeling, Simulation, Information Technology, and Processing
These focuses on advances in foundational capabilities for flight computing and ground computing; physics-based and data-driven modeling, simulation, and software development; and information and data processing frameworks, systems, and standards.
TA 12: Materials, Structures, Mechanical Systems, and Manufacturing.
Materials are the enablers behind the structures, devices, vehicles, power, life support, propulsion, entry, and many other systems that NASA develops and uses to fulfill its missions. NASA’s vision to extend exploration into deep space requires challenging structural innovation. Mechanism systems are essential to performing the functions required at virtually every stage of spaceflight operations in order to achieve specified mission objectives. Advanced manufacturing capabilities are required for significant improvements in cost, schedule, and overall performance.
TA 13: Ground and Launch Systems.
The primary goal of ground and launch system technologies is to provide the launch capability required to enable exploration while reducing operations and maintenance costs by 50%, and achieving a 50% reduction in ground safety mishaps, process escapes, and close calls.
TA 14: Thermal Management Systems
These maintain temperatures of a sensor, component, instrument, spacecraft, or space facility within the required temperature limits, regardless of the external environment or the thermal loads imposed from operations.
TA 15: Aeronautics.
The NASA Aeronautics research strategy is to develop and demonstrate revolutionary technologies that enable global air transportation that is safer, more efficient, and more environmentally friendly for the next 30 years and beyond.
Cross cutting technologies are the technologies that cut across many technology areas
Autonomous Systems and Artificial Intelligence
Autonomy is a critical crosscutting technology for improving the performance and reducing the risks for a wide range of NASA human exploration, robotic, and aeronautics applications. As exploration missions take humans deeper into space, autonomous systems will be needed to enable astronauts and their vehicles to function effectively and efficiently when operating independently of ground control.
Avionics are electronic systems at the center of the command, control, and monitoring capabilities, including electronics for spaceflight instrumentation, communications, tracking, and human interfaces.
Long-duration crewed missions, space-based observatories, and solar system exploration will require highly reliable, fault-tolerant avionic systems. Communication delays, the challenging orbital dynamics of Near-Earth Asteroids, and extreme science missions require increased autonomy for on-board decision infrastructures.
All human exploration missions require space suits, either for occupant protection during dynamic flight phases and crew survivability during off-nominal events or to facilitate Extravehicular Activities (EVAs) for exploration and repair operations outside of a space vehicle. Space suits are, in effect, miniature human form-fitting spacecraft, containing many of the systems common to a spacecraft, such as life support, thermal control, avionics, power distribution and energy storage, impact protection, propulsion, and communications.
Over the next decade, IT will be critical to the success of NASA’s long-duration missions. Technology advances in data management and communications, artificial intelligence, statistics, instrumentation, scalable cyber infrastructures, visualization, and analysis algorithms are needed to support data-intensive operations and Agency objectives. Automated corruption detection or self-healing for massive or rapidly generated database are essential to NASA’s Big Data support.
In-Situ Resource Utilization
Any program to extend human presence and operations on extraterrestrial bodies requires that we learn how to utilize the indigenous resources. The purpose of In-Situ Resource Utilization (ISRU) is to locate, harness, and utilize resources (both natural and discarded material) at the site of exploration to create products and services for subsequent use. Potential space resources include water/ice, solar wind implanted volatiles (hydrogen, helium, carbon, nitrogen, etc.), metals and minerals, atmospheric constituents, solar energy, regions of permanent light and darkness, trash and waste from human crew, and discarded hardware that has completed its primary purpose.
After more than 50 years of human space activities, orbital debris has become a serious problem in the near-Earth environment. As of 2015, the total mass of debris in orbit has exceeded 6,000 tons.
Some of the technology areas needed to address the orbital debris challenge are Radar, optical, and in-situ measurements to better characterize the orbital debris population from large (>10 centimeters (cm)) to small (< 0.1 millimeter (mm)) and from low-Earth orbit (LEO) to geostationary orbit (GEO). Others are modeling of the current and future orbital debris environment, modeling of satellite explosions and collisions and the fragment mass, density, and shape distributions and modeling of object reentry survivability assessments.
Radiation and Space Weather
Deep-space and long-duration missions, where both crew members and spacecraft no longer benefit from the protection of Earth’s magnetic fields, are considered high risk for adverse radiation impacts. Long term exposure of astronauts to radiation is problematic and the effect that space radiation has on spacecraft electronics and software is equally challenging. The ability to predict space radiation events and protect both human and human-built systems from these events is of crucial interest to NASA in order to explore space beyond low-Earth orbit.
Sensors are devices that respond to external stimuli, such as motion, heat, or light, and respond in a particular way to convert the stimuli into a measurable quantity such as an analog or digital representation. In order to conduct science missions—whether in-situ on a planetary surface or remotely from orbiting satellites and probes—NASA’s scientists need sensors of all types.
Some examples include flow sensors, which are required for the proper operation of a rocket motor, chemical sensors to detect hazardous chemical leaks on the International Space Station (ISS), and thin film sensors that operate in harsh environments for surface measurement in aeronautics propulsion system research.
Thermal Protection Systems
Thermal Protection Systems (TPS) protect spacecraft from extremely high temperatures and heating during all mission phases, and are very often low-to-no-fault-tolerant, critical systems that constitute a significant mass fraction of spacecraft. TPS technologies require exotic materials and structures necessary for reentry and propulsion systems, and high-temperature sensors and electronics for health monitoring and communication through plasma during reentry.