The development of earth independence extends human presence beyond low Earth orbit and cislunar space and onto Mars. Missions during this stage of exploration range from 2-3 years with safe return of the crew to Earth taking months. Johnson Space Center provides agency leadership for the development and analysis of human spaceflight architectures, mission plans, and surface system definitions. JSC is a leader in technology developments for Habitats, Space Suits, In-Situ Resource Utilization, and Entry, Decent, and Landing Systems and provides unique mission integration and test environments. Johnson Space Center is the agency’s lead center for Astromaterials and a leader in the science of planetary destinations.
Entry, Descent, and Landing
Entry, Descent, and Landing technologies ensure precise and safe landings on planetary surfaces and encompass the full range of sensors and components, guidance and navigation systems, testing and qualification, and mission operations capable of achieving the following:
- Enable heavier payloads travelling at faster velocities to enter and descend through atmospheres and land safely with higher precision than currently possible.
- Provide highly reliable AAE systems for human and science missions that are capable of higher entry speeds, greater payload mass, improved approach navigation, and operation in extreme environments.
- Provide greater deceleration in the supersonic and subsonic regimes in a manner that does not reduce landing accuracy or result in transient unsteadiness or loss of performance in the transonic regime.
- Enable reliable landings on very rough and uncertain terrain for human-scale Mars vehicles with large masses.
- Provide a thorough understanding of the flight environment for vehicle design and develop accurate tools for analyzing the end-to-end vehicle performance.
Mars Surface Systems
At the Johnson Space Center and other NASA Centers, high level mission objectives for future human Mars missions are translated into specific surface systems and concepts of operations to achieve these objectives. At present NASA has embarked on an approach that will allow human crews to live and work productively on Mars for extended periods of time and gradually become independent of support from Earth. This requires not only an understanding of the Mars mission requirements but also constraints imposed by the Martian environment and the “known unknowns” that must be investigated and incorporated into an overall approach to pioneering on the surface of Mars.
The Johnson Space Center is responsible for identifying and evaluating candidate locations on the surface where humans could live and work productively. Concepts such as the Exploration Zones and adaptation of the “field station” have originated here. Adaptation and integration of specific surface system design concepts to achieve mission objectives is also a key aspect of Johnson Space Center’s role in the overall process of becoming “Mars Ready” for these future missions.
Mission Environments, Integration, and Testing
Mission success through all stages of the Journey to Mars relies on the integration of science and engineering into all aspects of human exploration. Mission relevant environments are key to testing a wide range of technologies, tools, and techniques in addition to trainingthe astronaut and ground operations crews in immersive environments. Achieving early integration of science, engineering, system operations, and prototype testing in a mission relevant environment will greatly increase the mission returns, reduce the risks, and improve the affordability of deep-space missions. This includes bio-medical systems, astronaut health and performance, mission operations concepts, communications, EVA, field science, robotics, and much more. At Johnson Space Center and other partnering centers, multi-disciplinary science and engineering teams design and carry out authentic mission tests to mature technologies and advance our readiness for deep space human exploration.
Space Radiation Protection
Space radiation risks to astronauts must be reduced to the lowest achievable level. New technologies are being developed to increase crew mission duration in the free-space radiation environment while remaining below the space radiation permissible exposure limits (PELs). These technology development objectives center on the following:
- Risk Assessment Modeling: Reduce uncertainty in assessing the risk of death due to radiation exposure and improve cancer risk assessments as well. Include circulatory and central nervous system (CNS) effects in assessments.
- Radiation Mitigation and Biological Countermeasures: Extend the number of safe days in space by developing biological countermeasures that reduce radiation health risks by 50% for the mission duration through small, low-mass, low-power, crew-friendly sensors that monitor the radiation environment.
- Radiation Environment Modeling: Improve the ability to predict future space weather events and their duration in order to prepare and protect the crew.
Robotics and Autonomous Systems
Human exploration will require leveraging robotic systems in all phases of the mission as precursors to crewed missions, as crew helpers in space, and as caretakers of assets left behind. The goals are to extend our reach into space, expand our planetary access capability, increase our ability to manipulate assets and resources, support our astronaut crews during their space operations, extend the life of the systems they leave behind, and enhance the efficacy of human operations. To achieve these ends, robotic capabilities will be extended in these areas:
- Sensing and Perception: Provide situational awareness for exploration robots, human-assistive robots, and autonomous spacecraft; and improve drones and piloted aircraft.
- Mobility: Reach and operate at sites of scientific interest in extreme surface terrain or free-space environments.
- Manipulation: Increase manipulator dexterity and reactivity to external forces and conditions while reducing overall mass and launch volume and increasing power efficiency.
- Human-System Interaction: Enable a human to rapidly understand the state of the system under control and effectively direct its actions towards a new desired state.
- System-Level Autonomy: Enable extended-duration operations without human intervention to improve overall performance of human exploration, robotic missions, and aeronautics applications.
Science and Planetary Destinations
We explore to extend our human presence throughout our solar system. We also explore to enrich our scientific understanding of other planets, our Moon, and nearby asteroids. There is a mission critical need to understand the varied and extreme planetary surfaces we will visit on the Journey to Mars. The harsh, rocky environments of the Moon, asteroids, Mars, and other destinations experience a wide range of temperatures, gravity, radiation, rock and mineral types, dust, and other environments that must be understood to correctly design spacecraft, landing systems, environmental and life support, space suites, ISRU systems, and science instruments. Johnson Space Center leads the agency in Astromaterials Curation and research into these planetary destinations as a resource for astromaterials and simulants for testing and analysis, and actively participates in active robotic missions on Mars as well as past, current, and future human science exploration.
Introduction: Choosing the Resistor to Use With LEDs
Lets get right to it:
Each of the steps do the same thing. Step 1 is the simplest and we go downhill from there.
No mater what way you choose you must first know these three things:
- Supply voltage This is how much power you’re putting into the circuit. Batteries and wall warts will have the output voltage printed on them somewhere. If you’re using multiple batteries*, add the voltage together.
- LED Voltage Sometimes “Forward Voltage” but usually just abbreviated “V”.
- LED Current Sometimes “Forward Current”. This is listed in milliamps or “mA”.
Both of these last two can be found on the packaging for your LEDs or on your supplier’s web site. If they list a range (“20-30mA”) pick a value in the middle (25 in this case). Here are some typical values, but use your own values to be sure you don’t burn out your LEDs!:
Red LED: 2V 15mA
Green LED: 2.1V 20mA
Blue LED: 3.2V 25mA
While LED: 3.2V 25mA
April 16, 2018
Thank you for contacting me to express your support for robust science funding. I appreciate hearing from you and welcome the opportunity to respond to your comments.
Like you, I believe that investing in the sciences is critical to the United States remaining globally competitive and to our quality of life in general. I will continue to support policies that will strengthen and broaden our knowledge and ensure that public policy is guided by sound science.
As a community psychologist, I am a strong supporter of research that allows people to lead healthier lives. As a nation, we have a long and proud record of accomplishment in scientific research that has brought cures and treatments to billions across the globe.
During the last Congress, I cosponsored and voted in favor of the 21st Century Cures Act which was signed into law. This boosted funding for the National Institutes of Health (NIH) as well as the Food and Drug Administration (FDA), which approves new treatments and cures. This bill made a number of changes to the drug approval process to ensure that medical cures more quickly reach the people who need them most while also maintaining patient safety.
I will continue to support, as I have every year I have been in Congress, robust funding for the National Science Foundation, National Institutes of Health, and our health research programs. In addition, I will continue to advocate for funding for public health, health planning, and health research in Congress.
Again, thank you for taking the time to contact me about this important issue. Your comments help me to better represent the people of our Congressional District. Please stay in touch, and if I can be of any further assistance, please do not hesitate to email me through my website at www.lowenthal.house.gov or call my Washington, D.C. office at (202) 225-7924.
A next step in finding distant planets Hunting for faraway worlds, carefully
Are there ‘other places like Earth?’ A new NASA mission is well-equipped to pursue that question.
By Amina Khan
On a cold, clear night in January, MIT astrophysicist George Ricker and his students stepped onto a rooftop on campus and aimed a camera at the highest point in the sky.
That camera, an engineering model of the four being launched with NASA’s TESS mission, revealed a night so thick with stars that they obscured the normally distinct constellations.
“In two seconds you could see things that were a hundred thousand to a million times fainter than what you could see with your naked eye,” said Ricker, the mission’s principal investigator.
The test offered a small taste of what TESS, the Transiting Exoplanet Survey Satellite, will discover after it launches, which could occur as early as Monday afternoon. The spacecraft will scan almost all of the sky for neighboring stars, searching for the dips in their brightness that signal the presence of a planet.
The goal: to find planets that are smaller than Neptune, with a radius less than about four times that of Earth. Scientists will then use other telescopes to measure the masses of 50 of them.
A few of the worlds TESS finds may be small, rocky bodies, like Earth. And a few of those might, just possibly, be habitable places for life as we know it.
“It’s very exciting,” Ricker said. “We’re getting a chance to potentially answer a question that humanity’s always been interested in: What’s in the sky? And are there other beings, other places like Earth?”
Astronomers have been searching for planets beyond our solar system for decades.
Some of their first discoveries were confirmed in the 1990s. Among them were exoplanets that were detected by ground-based telescopes that looked for the periodic wobble in a star’s motion caused by a planet’s tiny tug — a technique known as the radial velocity method. Others were found by searching for variations in the predictable rhythms of pulsars.
About 325 exoplanets had been discovered by the time NASA launched the Kepler Space Telescope in 2009. It employed the transit method, staring deep into a patch of sky and looking for the shadows cast by planets as they crossed in front of their host stars.
Kepler was a full-time planet hunter, and it revolutionized astronomers’ understanding of exoplanets. It was particularly interested in finding Earth-sized planets orbiting sun-like stars at a distance where water on the surface could be stable in liquid form — the so-called habitable zone.
To date, data from its primary mission have turned up 2,343 confirmed and 2,244 candidate exoplanets and revealed that there could be more planets than stars in the Milky Way. Many of them are in multiple-planet systems, and a large share of them appear to be super-Earths — a class that’s bigger than our planet but smaller than Neptune.
TESS, which is managed by NASA’s Goddard Space Flight Center in Greenbelt, Md., will take the torch that Kepler lighted and run with it.
Kepler stared at just one small patch of the heavens whose stars are up to 3,000 light-years away. That made it difficult to conduct follow-up studies with other telescopes.
TESS, by contrast, will target stars that are less than 300 light-years away — and it will look in nearly all directions.
“Kepler took a poll of stars in the galaxy to find out what planets they harbor,” said Natalie Batalha, Kepler’s project scientist at NASA Ames Research Center. “TESS is getting to know the neighbors.”
It will do that with four cameras, each focused on a different part of the sky. Together, the cameras will stare at a vertical strip of the celestial sphere stretching from the pole to the equator, proceeding to a new strip every 27 days.
TESS will be on the lookout for the regular drops in brightness caused by a planet crossing in front of its stellar host and blocking a tiny amount of starlight. The bigger the planet is relative to its star, the deeper the drop. The more frequently these dips occur, the shorter a planet’s orbit and the closer it is to its star. Scientists need to witness these dimmings multiple times before they can tell whether it’s truly evidence of a circling world.
It will take about a year to scan the heavens above the Southern Hemisphere and another year to finish the Northern Hemisphere. By the end of its two-year primary mission, it will have imaged roughly 85% of the sky. Astronomers anticipate that TESS will find on the order of 500 super-Earths, which don’t exist in our solar system.
“The number of known planets in the solar neighborhood is slowly growing right now,” Batalha said. “TESS will bust that open wide.”
Because they lie so close to us, the stars in the TESS survey will be brighter, which will make it easier for future missions like NASA’s James Webb Space Telescope to search for signs that their planets could be habitable.
That work will require telescopes to examine the tiny fraction of starlight that passes through a planet’s thin shell of atmosphere (if it has one) and look for the fingerprints of life-friendly molecules like free oxygen, methane and water. Separating those weak signals from the rest of the star’s light will be exceedingly difficult for small, rocky planets with compact atmospheres.
“They’re going to become not just names in a catalog — they’re going to become destinations, they’re going to take on personalities,” Batalha said of those planetary profiles. “We’re going to learn so much more about them than we ever could with the Kepler planets because they’re so nearby.”
TESS will be primed to identify the worlds circling red dwarfs, the small, dim stars that make up about three-quarters of the stars in the sky.
Red dwarfs are so small that their planets seem relatively big, which makes them easier to detect. And because the stars are so dim, their habitable zones are much more compact, which means TESS could witness multiple transits within each of its 27-day observing periods.
The space-based telescope could also study all kinds of other celestial phenomena, including supernovas, flare stars and active galaxies.
“When you have a space mission in the sky, usually your best discoveries aren’t the ones you planned,” said MIT astrophysicist Sara Seager, the mission’s deputy science director.
Because of those tight observing windows, the spacecraft won’t be able to pick up planets with longer Earth-sized orbits, as Kepler could. But since the 13 observation strips in each hemisphere overlap at the poles, TESS will have eyes on both the northern and southern polar skies for nearly a year at a time. In a few years — if TESS’ two-year mission is extended long enough — it could eventually find the kinds of rocky, habitable-zone planets that Kepler could.
And TESS could potentially last much longer than Kepler, which is expected to run out of fuel within the next few months.
That’s because Ricker’s team designed a new kind of orbit — a highly elliptical, 13.7-day trip that allows the spacecraft to avoid damage from Earth’s Van Allen radiation belts, while also bringing it close enough to regularly send back loads of image data. The orbit is so stable that the spacecraft won’t need to burn up fuel to keep itself in place.
“I cannot wait for the data to roll out,” said Debra Fischer, a Yale University astronomer who is not involved in the mission. “It is just going to be incredibly exciting.”
Humans haven’t developed the technology to reach even the nearest stars, but that may change in the coming generations, Ricker said. If it does, Earth will already know where to send small robotic explorers.
“We basically will have discovered the most interesting systems,” he said. “The TESS planets are going to be the ones you’re going to look at.”
Bob Barboza is an educator, STEM journalists, composer and founder of the Barboza Space Center STEM & STEAM fellowship Program and Kids Talk Radio Science. http://www.barbozaspacecenter.com/ He trains Jr. astronauts, engineers, and scientists for the “Occupy Mars Learning Adventures.” His students and interns are learning robot and satellite design, building, and repair.
Bob also teaches the Summer Barboza Space Center Fellowship Program for the Long Beach Unified School District. He has been using the NAO robot since 2013 when he realized NAO was the tool for him to get kids excited about going to Mars, “NAO has legs, hands, and it’s totally, programmable which makes it the best tool to experiment going to Mars and excite the students to learn more”
“Every time the students program the NAO Robot they feel amazed and Inspired to do more complex learning with him”. His High Schools students feel ready to work in Engineering programs, the specific projects with the robot last one week. And they really like the fact that they can program NAO and see the results immediately. “Their work is from typing to action,” Bob said. NAO is an actor in the Occupy Mars Learning Adventure simulation program.
For Bob, the educational and social impact that he has noticed is that his program is appearing at more educational and robot events, and the audience seems to enjoy the special workshops and overall experience. The impact on the community and the rest of the district has been positive. They will participate in two city events centered around letting the community get a deeper understanding of robots and how they are used in education.
Lastly, to Bob, NAO is the best experimental tool to get students around the world excited about working together and studying STEM and STEAM++ project-based learning (science, technology, engineering, visual and performing arts, mathematics, computer languages and foreign languages) as they pursue careers in the Aerospace Industry. He will continue working to interact with more kids and transform the way of learning with NAO.