The Australian TV program ABC Stargazing Live with Brian Cox recently challenged its viewers to become citizen exoplanet finders. They succeeded within a couple of days in finding four “Super Earth” planets each about twice the size of earth.
Kepler observes thousands of stars and records the stars’ brightness for long continuous periods. If a star’s planet comes between the line of sight with the earth, a dip in the star’s brightness can be seen in the data.
The width and depth of the drop in the light and the frequency of the dips provides clues to the size of the planet and its orbital period and distance from its star.
While the above diagrams are very clean and unambiguous, most real data is noisy and messy. Human’s are still much better than computer algorithms in spotting structures and unexpected features in such data and that is why citizen science volunteers can provide very useful services for the pro scientists who are collecting the data, especially when there are huge amounts of such data.
In this case, the dips of four planets were seen in the light output of a star in the Aquarius constellation 600 light years from earth. This video provides more details about these exoplanets:
David says the shows this week are canceled “due to medical leave for dental surgery. See website newsletter & Upcoming Shows menu for suggested oldies”.
Sunday, April 23, 2017: 12-1:30 PM DST (3-4:30 PM EDT, 2-3:30 PM CDT): Please check the website newsletter and upcoming show menu for details for this program. If I can return, we will have an Open Lines discussion. If I am still on medical leave, I will let you know.
ZERO-G sends the message below about university research projects flown on the companies Boeing 727 that provides periods of weightlessness by flying parabolic trajectories.
ZERO-G Research Flights Advance Technology for Future Deep-Space Missions As Part of NASA’s Flight Opportunities Program, Research Groups
Tested Systems in Zero Gravity Crucial to Long-Term Space Missions
ORLANDO, Fla. – April 6, 2017 – As part of NASA’s Flight Opportunities Program, Zero Gravity Corporation (ZERO-G®) recently worked with research groups from University of Florida, Carthage College and University of Maryland to validate technology designed to further humanity’s reach into space. A collection of flights on G-FORCE ONE, ZERO-G’s specially modified Boeing 727, gave researchers the chance to run experiments and test innovative systems in the only FAA-approved, manned microgravity lab on Earth.
“G-FORCE ONE is the perfect test bed for space-bound technology and is one of the last steps before sending experiments into orbit,” said Terese Brewster, CEO of ZERO-G. “The data collected from these universities and future groups who do research with us is vital for the future of space exploration.”
The below experiments were conducted by groups during the research flight:
Rocket Propellant Thermal Management System for Deep-Space Missions University of Florida
Long-duration space travel to Mars and beyond will utilize primarily liquid oxygen and hydrogen – cryogens – for rocket propellant. Before these cryogens can be injected into the engine as liquids, transfer lines must be cooled to temperatures below 20 to 80 Kelvin, approximately minus 425 to minus 315 degrees Fahrenheit. This cooling process is typically done the initial flow of liquid cryogens, which are then vented outside the spacecraft as vapor. For long-distance space missions, the transfer line “chilldown” must be accomplished with minimal consumption of cryogen to conserve that material for propellant use.
A team of nine undergraduate and four graduate students led by Professor Jacob Chung developed a special coating for the inside of the propellant transfer pipe to enable a faster cooling process and minimize cryogen loss. The team’s system proved viable in extreme temperature changes and maintained integrity in microgravity and high G-forces during the research flight with ZERO-G. Findings show that coating a transfer pipe reduced chilldown time and fuel consumption by as much as 50 to 70 percent. The team will continue its research on perfecting the technology and revolutionizing space travel.
Measuring Propellant Levels in Low Gravity Carthage College
Current methods to gauge spacecraft propellant in low gravity have a margin of error of five to 10 percent of the total propellant mass, creating a challenge for NASA’s goal of a sustained human presence in space. These limitations also cost the satellite industry millions of dollars as satellites are required to carry an extra 10 percent of fuel to make up for inaccuracies.
Working with engineers at Kennedy Space Center, a team of students led by Carthage College Professor Kevin Crosby developed the Modal Propellant Gauging (MPG) Project. MPG is a non-invasive, real-time and low-cost method of measuring liquid propellant volume by analyzing sound waves produced by vibrations applied to the tank. Findings show MPG has a margin of error less than two percent over a range of propellant volumes. This increase in accuracy is equivalent to an annual industry-wide savings of tens of millions of dollars.
Creating Reliable Models for the Effects of Gravity on Flow Boiling Heat Transfer University of Maryland
Future space missions will require lighter, smaller and more powerful spacecraft, which will utilize two-phase thermal systems. Currently, single-phase thermal subsystems are used due to lack of reliable models to predict two-phase system performance in various types of gravity. In order to design efficient heat removal equipment for these spacecraft, a heat transfer database and dependable models must be developed.
Researchers from the Department of Mechanical Engineering at University of Maryland designed an experiment to collect the data and develop the models needed. Unlike previous work in this area, the team obtained local measurements using temperature-sensitive paints. Data analyzed in Martian gravity, lunar gravity and low-G will determine how inlet subcooling, wall heat flux and flow rate are affected by varied gravity environments.
ZERO-G’s current schedule includes additional research flights during the week of November 13, 2017. For more information about the ZERO-G research program, please visit www.gozerog.com and click on the Research Tab.
About ZERO-G: Zero Gravity Corporation is a privately held space entertainment and tourism company whose mission is to make the excitement and adventure of space accessible to the public. ZERO-G is the first and only FAA-approved provider of weightless flight in the U.S. for the general public; entertainment and film industries; corporate and incentive markets; non-profit research and education sectors; and the government. ZERO-G’s attention to detail, excellent service and quality of experience combined with its exciting history has set the foundation for the most exhilarating adventure-based tourism. For more information about ZERO-G, please visit www.gozerog.com.
NASA scientists have just released the first new global map of Earth at night since 2012. By studying Earth at night, researchers can investigate how cities expand, monitor light intensity to estimate energy use and economic activity, and aid in disaster response.
Credits: NASA’s Goddard Space Flight Center/Kathryn Mersmann
NASA scientists are releasing new global maps of Earth at night, providing the clearest yet composite view of the patterns of human settlement across our planet.
Satellite images of Earth at night — often referred to as “night lights” — have been a gee-whiz curiosity for the public and a tool for fundamental research for nearly 25 years. They have provided a broad, beautiful picture, showing how humans have shaped the planet and lit up the darkness. Produced every decade or so, such maps have spawned hundreds of pop-culture uses and dozens of economic, social science and environmental research projects.
These three composite images provide full-hemisphere views of Earth at night. The clouds and sun glint — added here for aesthetic effect — are derived from MODIS instrument land surface and cloud cover products. Credits: NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA’s Goddard Space Flight Center Download Americas image – Download Europe and Africa image – Download Asia and Australia image
But what would happen if night lights imagery could be updated yearly, monthly or even daily? A research team led by Earth scientist Miguel Román of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, plans to find out this year.
In the years since the 2011 launch of the NASA-NOAA Suomi National Polar-orbiting Partnership (NPP) satellite, Román and colleagues have been analyzing night lights data and developing new software and algorithms to make night lights imagery clearer, more accurate and readily available. They are now on the verge of providing daily, high-definition views of Earth at night, and are targeting the release of such data to the science community later this year.
Composite image of continental U.S. at night, 2016. Credits: NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA’s Goddard Space Flight Center
Since colleagues from the National Oceanic and Atmospheric Administration and NASA released a new Earth at night map in 2012, Román and teammates at NASA’s Earth Observing Satellite Data and Information System (EOSDIS) have been working to integrate nighttime data into NASA’s Global Imagery Browse Services (GIBS) and Worldview mapping tools. Freely available to the science community and the public via the Web, GIBS and Worldview allow users to see natural- and false-color images of Earth within hours of satellite acquisition.
Composite image of Mid-Atlantic and Northeastern U.S. at night, 2016. Credits: NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA’s Goddard Space Flight Center
Today they are releasing a new global composite map of night lights as observed in 2016, as well as a revised version of the 2012 map (8 MB jpg | 265 MB jpg). The NASA group has examined the different ways that light is radiated, scattered and reflected by land, atmospheric and ocean surfaces. The principal challenge in nighttime satellite imaging is accounting for the phases of the moon, which constantly varies the amount of light shining on Earth, though in predictable ways. Likewise, seasonal vegetation, clouds, aerosols, snow and ice cover, and even faint atmospheric emissions (such as airglow and auroras) change the way light is observed in different parts of the world. The new maps were produced with data from all months of each year. The team wrote code that picked the clearest night views each month, ultimately combining moonlight-free and moonlight-corrected data.
Composite image of Nile River and surrounding region at night, 2016. Credits: NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA’s Goddard Space Flight Center
Román and colleagues have been building remote sensing techniques to filter out these sources of extraneous light, gathering a better and more consistent signal of how human-driven patterns and processes are changing. The improved processing moves Suomi NPP closer to its full potential of observing dim light down to the scale of an isolated highway lamp or a fishing boat. The satellite’s workhorse instrument is the Visible Infrared Imaging Radiometer Suite (VIIRS), which detects photons of light reflected from Earth’s surface and atmosphere in 22 different wavelengths. VIIRS is the first satellite instrument to make quantitative measurements of light emissions and reflections, which allows researchers to distinguish the intensity, types and the sources of night lights over several years.
Composite image of Europe at night, 2016.
Suomi NPP observes nearly every location on Earth at roughly 1:30 p.m. and 1:30 a.m. (local time) each day, observing the planet in vertical 3000-kilometer strips from pole to pole. VIIRS includes a special “day-night band,” a low-light sensor that can distinguish night lights with six times better spatial resolution and 250 times better resolution of lighting levels (dynamic range) than previous night-observing satellites. And because Suomi NPP is a civilian science satellite, the data are freely available to scientists within minutes to hours of acquisition.
[Chicago and Lake Michigan area in 2016. See NASA posting for comparison with 2012 image of same area.]
[India in 2016. See NASA posting for comparison with 2012 image of same area.]Armed with more accurate nighttime environmental products, the NASA team is now automating the processing so that users will be able to view nighttime imagery within hours of acquisition. This has the potential to aid short-term weather forecasting and disaster response.
“Thanks to VIIRS, we can now monitor short-term changes caused by disturbances in power delivery, such as conflict, storms, earthquakes and brownouts,” said Román. “We can monitor cyclical changes driven by reoccurring human activities such as holiday lighting and seasonal migrations. We can also monitor gradual changes driven by urbanization, out-migration, economic changes, and electrification. The fact that we can track all these different aspects at the heart of what defines a city is simply mind-boggling.”
For instance, VIIRS detected power outages in the wake of Hurricane Matthew, a major storm that struck the northeastern Caribbean and the southeastern United States in late September 2016. NASA’s Disasters Response team provided the data to colleagues at the Federal Emergency Management Agency; in the future, NASA, FEMA and the Department of Energy hope to develop power outage maps and integrate the information into recovery efforts by first responders.
The NASA team envisions many other potential uses by research, meteorological and civic groups. For instance, daily nighttime imagery could be used to help monitor unregulated or unreported fishing. It could also contribute to efforts to track sea ice movements and concentrations. Researchers in Puerto Rico intend to use the dataset to reduce light pollution and help protect tropical forests and coastal areas that support fragile ecosystems. And a team at the United Nations has already used night lights data to monitor the effects of war on electric power and the movement of displaced populations in war-torn Syria.
In a separate, long-term project, Román is working with colleagues from around the world to improve global and regional estimates of carbon dioxide emissions. The team at NASA’s Global Modeling and Assimilation Office (GMAO) is combining night lights, urban land use data, and statistical and model projections of anthropogenic emissions in ways that should make estimates of sources much more precise.
