The International Space Station – A unique platform for Earth observation

International Space Station

International Space Station (image: NASA).

From the launch of its first module in 1998, to its first onboard crew in 2000, to today’s expansive labyrinth of space laboratories and solar arrays, the International Space Station is a technological marvel and an icon of human innovation. The ISS is well known as a research facility for medicine, biology, physical science, physiology, space flight, and cutting-edge engineering.

But did you know the ISS is home to a unique collection of facilities that can be used for Earth observing instruments. These include the Columbus – External Payload Facility (Columbus-EPF), the Expedite the Processing of Experiments to the Space Station Logistics Carrier (ELC), the Japanese Experiment Module – Exposed Facility (JEM-EF) and the Window Observational Research Facility (WORF). The Columbus-EPF, ELC and JEM-EF support external payloads, which means remote sensing instruments can be mounted on the outside of the ISS. And the WORF supports internal payloads by providing a very high optical quality optical window through which instruments can view the Earth below.

Advantages of using the ISS as a remote sensing platform include the capacity to install new instruments with relative ease (at least compared with launching free flying satellites), the ability to remove instruments and transport them to ground for post-mission analysis, and in some cases the option for crew interaction with the instrument while onboard the station. The ISS also has a unique orbit that differs from most Earth observing satellites, thus allowing image collection at different times of the day and under different illumination conditions than would otherwise be possible. These same orbit characteristics; however, can also be a disadvantage with respect to image uniformity and operational requirements. Additionally, in some cases the solar arrays can interfere with observations during certain situations. Nonetheless, the ISS is an excellent facility to test new instruments and explore new remote sensing capabilities.

So what are some of the instruments that have flown on the ISS? There are HICO (Hyperspectral Imager for the Coastal Ocean) and RAIDS (Remote Atmospheric and Ionospheric Detection System), which are integrated into a single payload installed on the JEM-EF. As the name implies, HICO is a hyperspectral instrument that has been optimized for imaging the nearshore aquatic environment. RAIDS is used for measuring the major constituents of Earth’s upper atmosphere, specifically the thermosphere and the ionosphere. There is also the EVC (Earth Viewing Camera), which is part of the European Technology Exposure Facility (EuTEF) deployed on Columbus-EPF. EVC is a commercial off-the-shelf digital camera used to capture color images of the Earth’s surface. A final example is ISSAC (International Space Station Agricultural Camera), which is installed as an internal payload on WORF. ISSAC is a multispectral camera measuring wavelengths in the visible and near infrared that primarily targets agricultural areas in the northern Great Plains. ISSAC is also particularly exciting, since it was largely built and operated by students at the University of North Dakota.

Those are just a few of the exciting instruments on the ISS. There are many others… and more instruments planned for future missions.

Are you involved in instrument development or image analysis related to the ISS? We’d love to hear your thoughts and stories and share them with the community.

For more about the ISS: http://www.nasa.gov/mission_pages/station/main/

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The NEON Science Mission – Open access ecological data

NEONInterested in assessing the ecological impacts of climate change? How about investigating the complex dynamics of ecological response to land use change and invasive species? What types of data would you need to perform such research at regional and continental scales? These are just some of the ambitious science questions being addressed by NEON – the National Ecological Observatory Network.

Sponsored by the U.S. National Science Foundation, NEON is an integrated network of 60 sites located throughout the U.S. where infrastructure is being put in place to collect a uniform array of scientific data. The hypothesis is that by providing consistent measurements and observations across the U.S., scientists will be better able to answer critical questions related to environmental change. Originally conceived in 1997, and followed by many years of planning, NEON entered its construction phase in 2012. Current plans are for the network to be fully operational in 2017, and for data from NEON to be collected for 30 years.

The 60 NEON sites encompass the continental U.S., Alaska, Hawaii and Puerto Rico. Sites were selected to represent a diverse range of vegetation communities, climate zones, land types, and land-use categories. The current list of NEON data products to be collected at each site include over 500 different entries, including both field and remote sensing observations. Items range from as detailed as genetic sequences and isotope analyses of field samples to as broad as temperature and wind speed measurements from meteorological instruments. Additionally, in what has become a welcome trend within the community, NEON data is being distributed using an open access policy.

Of particular interest to the remote sensing community is that NEON includes an Airborne Observation Platform (AOP) that will be used to collect digital photography, imaging spectroscopy data, and full-waveform LiDAR data. To accommodate the geographic distribution of NEON sites, this same suite of remote sensing instrumentation will be deployed on three different aircraft. Note that remote sensing data collection, as well as testing and validation of analysis protocols, has already begun and preliminary data is available upon request.

Given its scope, it is clear that the data and information derived from the NEON project will have a profound impact on our understanding of the natural environment and our ability to assess ecological change.

For more information on NEON: http://www.neoninc.org/

NASA Earth Science Today – A look at current satellites

Earth

Earth from far above (image courtesy NASA)

Presently orbiting the Earth are a complex international array of satellites, providing services for navigation, communication, astronomy, security, and weather. Amongst these are also satellites dedicated to monitoring the environment in which we live, including our atmosphere, land and oceans. A previous post examined NASA Earth observing satellites planned for launch in the coming years. Today we look at some of the many NASA satellites that are currently in orbit around our planet.

TERRA: The heft of this satellite may be surprising, close to the size of a small bus and weighing over 11,000-lbs at launch. With this size, however, come extensive capabilities. The Terra satellite, an international mission launched in 1999, contains five separate instruments: ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer), CERES (Clouds and the Earth’s Radiant Energy System), MISR (Multi-angle Imaging SpectroRadiometer), MODIS (Moderate Resolution Imaging Spectroradiometer), and MOPITT (Measurement of Pollution in the Troposphere). Together these instruments provide a unique capacity to observe Earth’s land, ocean, atmosphere, snow, and ice, helping address questions related to climate variability and change, atmospheric composition, weather, and the water, carbon and energy cycles.

AQUA: This is a companion satellite to Terra, which, along with a collection of other existing and planned satellites, is an integral part of the multi-satellite Earth Observing System (EOS). Aqua was launched in 2002, and carries a total of six instruments: AIRS (Atmospheric Infrared Sounder), AMSU-A (Advanced Microwave Sounding Unit), HSB (Humidity Sounder for Brazil), AMSR-E (Advanced Microwave Scanning Radiometer for EOS), MODIS (Moderate Resolution Imaging Spectroradiometer), and CERES (Clouds and the Earth’s Radiant Energy System). Aqua and Terra have different orbit characteristics; hence the presence of MODIS and CERES on both satellites allows the same type of imagery to be collected at different times of the day.

TRMM (Tropical Rainfall Measuring Mission): As would be expected from its name, the mission of this satellite is focused on measuring and understanding precipitation patterns in the tropics. The mission also provides information of tropical latent heating characteristics, which will help scientists better model the global energy budget. TRMM was launched 1997 and carries five instruments: PR (Precipitation Radar), TMI (TRMM Microwave Imager), VIRS (Visible and InfraRed Scanner), CERES (Clouds and the Earth’s Radiant Energy System), and LIS (Lightning Imaging Sensor).

CloudSat: Unlike some of the other satellites, CloudSat carries a single instrument, the CPR (Cloud Profiling Radar). This instrument builds on the strong legacy of radar expertise at NASA, following the success of other instruments such as SRTM, SIR-A, SIR-B, SIR-C, QuickScat and SeaWinds. The CPR instrument on CloudSat, launched in 2006, measures the vertical profiles of clouds, providing valuable information on cloud structure and composition. Such data is a critical component in the study of climate and weather dynamics around the planet.

AURA: The four instruments aboard the Aura satellite, launched in 2004, are designed to examine Earth’s atmosphere. Measurements are targeted at better understanding trends in air quality, atmospheric composition, ozone distribution, and the climate. The instruments on Aura include: HIRDLS (High Resolution Dynamics Limb Sounder), MLS (Microwave Limb Sounder), OMI (Ozone Monitoring Instrument), and TES (Tropospheric Emission Spectrometer).

As evident from the above descriptions, a common theme among many of the Earth observing satellites is the co-location of multiple instruments on a single satellite platform. This is not only more efficient in terms of engineering, launch and management, but also facilitates the acquisition of multiple images from different types of instruments at the same time and place in orbit. Another theme is placing the same type instrument on different satellites, allowing image collection to be performed with more frequency. At the same time there are some satellites containing just one instrument with very specific measurement objectives. Together these satellites provide a multifaceted look at our planet that can be used to address a myriad of important science and societal questions.

For information on NASA’s satellite program, visit: http://science.nasa.gov/earth-science/missions/

The Future of NASA Earth Science – Preview of upcoming satellite launches

BlueMarble

The “Blue Marble” (image courtesy NASA)

Since its establishment in 1958, NASA has become well known for its advances in space exploration, and closer to home, highly recognized for its long history of scientific research using Earth observing satellites. From the early days of the TIROS program, whose first satellite was launched in 1960, to the more recent Landsat program, which has spanned 40 years of operation from 1972 to present (…and still going), NASA has been a leader in using satellite observations to improve our understanding of Earth.

NASA is currently operating an unprecedented number of Earth observing satellites, with many more in the pipeline. Here’s a look at some of the instruments NASA plans on launching in the coming years:

LDCM: Landsat Data Continuity Mission. As mentioned, the Landsat program has been operating since 1972. This longevity has enabled an enormous volume of remote sensing research to be accomplished, primarily focused on land surfaces but also including applications in the shallow coastal zone. With the lifespans of all the previous Landsat instruments reaching their end, and a hardware failure on Landsat 7, NASA recognized the need to move forward with a replacement to this important family of instruments. The LDCM will contain two instruments, the Operational Land Imager, measuring nine bands in the visible to short wave infrared, eight multispectral and one panchromatic, and the Thermal Infrared Sensor, measuring two thermal bands. LDCM, a collaborative mission between NASA and USGS, is currently scheduled for launch in early 2013.

GPM: Global Precipitation Measurement. The GPM mission, an international partnership co-led by NASA and JAXA (Japan Aerospace and Exploration Agency), builds on the success of TRMM (Tropical Rainfall Measuring Mission) launched in 1997. Whereas TRMM was designed to measure rainfall in the tropical and sub-tropical regions, GPM will acquire global measurements of both rainfall and snow. The concept for the GPM mission centers on a Core Observatory satellite, which will contain the latest advanced instruments to serve as a reference for calibrating measurements from a host of other operational satellites. The GPM Core Observatory contains two instruments, the GMI (GPM Microwave Imager) and the DPR (Dual-Frequency Precipitation Radar). The GPM Core Observatory is scheduled for launch in 2014.

OCO-2: Orbiting Carbon Observatory. The OCO-2 mission is a replacement satellite for the original OCO instrument launched in 2009 that unfortunately failed to make orbit. OCO-2 will acquire precise global measurements of atmospheric carbon dioxide, providing scientists with an unprecedented ability to explore the spatial and temporal patterns of carbon dioxide levels in our planet’s atmosphere. Measurements will be obtained using a single instrument containing three separate spectrometers to measure three narrow bands in the near-infrared that are sensitive to the presence of atmospheric gases.  OCO-2 is scheduled for launch in 2014.

SMAP: Soil Moisture Active Passive. Understanding soil moisture plays an important role in weather and climate forecasting, as well as predicting droughts, floods, landslides and agricultural productivity. To address this need, the SMAP mission will deliver global measurements of both soil moisture and its freeze/thaw state. SMAP measurements will be made using two L-band instruments, a radiometer and a synthetic aperture radar. Utilizing the L-band frequency allows measurements to be acquired night or day, irrespective of cloud cover, and even through moderate vegetation. SMAP is scheduled for launch in late 2014.

As each new instrument passes through the requisite design review process, it moves closer to approval for launch. Listed above are just some of the instruments approaching this auspicious achievement. There are many more on the way, with even more in the early planning stages. As a result of this ongoing progress, our ability to assess and monitor the condition of our planet has never been greater, with bold plans to continue improving this capacity in the future.

For more on NASA’s history, visit: http://history.nasa.gov/

For information on NASA’s satellite program, visit: http://science.nasa.gov/earth-science/missions/

HyspIRI Science Workshop Day 3 – Community data and international collaboration

The final day of the HyspIRI Science Workshop saw emphasis on international collaborations and development of shared data resources for the remote sensing community. Vibrant conversations were heard around the meeting throughout the day, covering an array of topics, but mostly focusing on how remote sensing can be used to assist in addressing key societal questions, such as climate and environmental change.

In addition to ongoing presentations related to the NASA HyspIRI mission, colleagues from other countries described international efforts to develop satellite instruments using similar technologies. For example, DLR, the German Aerospace Center, reported great progress with EnMAP (Environmental Mapping and Analysis Programme). An exciting aspect of the EnMAP mission is that agreements have recently been established to make data from the mission freely available to interested researchers. Advances are also being made with HISUI (Hyperspectral Imager Suite), which is being developed by the Japanese Ministry of Economy, Trade and Industry, and with PRISMA (PRecursore IperSpettrale della Missione Applicativa), which is a combined imaging spectrometer and panchromatic camera system under development by the Italian Space Agency.

HyspIRI - Guild et al.

Liane Guild (NASA ARC) discusses NASA’s COAST project with Sergio Cerdeira Estrada (CONABIO), Frank Muller-Karger (USF) and Ira Leifer (UCSB)

But it wasn’t all about satellites. Significant attention was also placed on the various airborne missions being used to demonstrate technology readiness, as well as perform their own valuable scientific investigations. This includes instruments such as AVIRIS, AVIRIS-ng, HyTES, PHyTIR, PRISM and APEX. The research being conducted using these instruments, which include both imaging spectrometers and multispectral thermal systems, is vital for validating engineering design components, data delivery mechanisms, calibration procedures, and image analysis algorithms. As a result, these instruments represent important steps forward in the progress of the HyspIRI mission. However, they also independently have great value, providing numerous opportunities for remote sensing scientists to develop new methods and deliver innovative research results.

In addition to the instruments themselves, scientists are also working towards improving overall data availability, calibration techniques and field validation methods. For example, NASA JPL is enlisting the remote sensing community to build an open-access spectral library, with the impressive goal of cataloging the spectral characteristics of as many of the Earth’s natural and manmade materials as possible. Such spectra represent important components in a variety of image classification and analysis algorithms. Other programs, such as the NEON project in the U.S. and the TERN project in Australia, are focused on collecting field data from example study sites and providing the data for others to use in their own research projects. It’s encouraging to see this level of community and collaboration.

As evidenced by the presentations and posters at the workshop, imaging spectrometry is a mature science with a wealth of proven application areas. However, this won’t stop scientists from continuing to innovate and push the limits of what can be achieved using this technology. There’s always a new idea around the next corner, and it’s workshops like this that help promote information exchange, development of new collaborations, and the creation of new research directions.

Presentations from the HyspIRI Science Workshop and information on the HyspIRI mission can be found at http://hyspiri.jpl.nasa.gov/

HyspIRI Science Workshop Day 2 – Imaging spectrometry applications

The second day of the 2012 HyspIRI Science Workshop focused on science applications. The day included both speaker presentations and an interactive poster session, allowing ample opportunity for attendees to interact and share research ideas. Of particular relevance was discussion on how HyspIRI, as a large-scale global mapping instrument, will enable exciting new research directions at regional and global scales.

HyspIRI - Simon Hook - Marisa Kalemkarian

Simon Hook (NASA JPL) and Marisa Kalemkarian (CONAE) discuss research on water temperature derivation at the Lake Tahoe validation site

Since the full range of science applications presented at the workshop are numerous, a few select examples are presented here to indicate the breadth of topic areas. Kevin Turpie (NASA Goddard Space Flight Center) presented a summary of the coastal and inland aquatic products accessible using HyspIRI data. Andrew French (USDA Agricultural Research Service) discussed methods for estimating evapotranspiration in rangelands. Robert Wright (University of Hawaii at Manoa) examined techniques for assessing volcanic activity. Dar Roberts (University of California, Santa Barbara) illustrated the capacity for evaluating pre- and post- fire vegetation characteristics. And Jeffrey Luvall (NASA Marshall Space Flight Center) presented capabilities for monitoring surface and temperature characteristics in urban environments.

Presentations also included discussion of image processing methods, such as validating algorithms for onboard lossless compression of image data and utilizing high performance computing for efficient generation of data products. Additional speakers focused on topics such as improved atmospheric correction techniques, ground validation requirements, and a host of advanced image analysis techniques.

Overall it was a highly informative workshop. In addition to providing an avenue to discuss the HyspIRI mission, the workshop also allowed colleagues to re-connect, new collaborations to be established, and new ideas and research directions to emerge. Everyone is looking forward to the next workshop, and eagerly anticipating the future launch of the HyspIRI instrument.

Presentations from the HyspIRI Science Workshop and information on the HyspIRI mission can be found at http://hyspiri.jpl.nasa.gov/