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Siqueira Part of Science Definition Team on $600-Million NASA Mission

Paul Siqueira

Paul Siqueira of the Electrical and Computer Engineering Department is one of 15 scientists selected by NASA to serve on the Science Definition Team of a $600-million collaborative mission between NASA and the Indian Space Research Organization (ISRO). In a meeting in Toronto on September 30, NASA Administrator Charles Bolden and K. Radhakrishnan, chairman of ISRO, signed two documents to launch a NASA-ISRO satellite mission to observe Earth and establish a pathway for future joint missions to explore Mars. The Science Definition Team is a group of 15 scientists nationwide who are considered experts in their field and who will help direct the formulation of the mission. See NASA press releaseRead related article from the BBC.

“My personal responsibility is one of 15 scientists competitively selected nationwide two years ago to work on the science applications for what was then a mission concept that did not have an international partner or requirements that would define the mission configuration,” explains Siqueira. “With the interaction of NASA and Jet Propulsion Laboratory staff scientists/engineers, the Science Definition Team works with the mission planners to determine a configuration and observing strategy to make best scientific use of the satellite resources (observing time, power consumption, data rate, etc.).”

As Siqueira notes above, in 2012 he was selected to serve on the Science Definition Team for a NASA space-borne radar mission meant to study “Earth Deformation, Ecosystem Science, and the Dynamics of Ice.” Now that project has evolved into the joint effort between NASA and ISRO.

Siqueira’s expertise falls into the Ecosystem Science category, which is related to carbon accounting, habitat identification, and monitoring of forest resources on Earth. In that context, Siqueira recently received a Harvard Bullard Fellowship to work at the Harvard Forest in Petersham, Massachusetts, in part to study the remote sensing of forest structure using airborne and satellite observations, such as NISAR will provide. 

“The advantage to a spaceborne mission is that such studies can be extended globally to make large-scale, high fidelity, measurements of the ecological environment,” observes Siqueira. “My background as an engineer and applications scientist is what have allowed me to effectively communicate (and understand) the tradeoffs involved in obtaining the needed science with the instrument that will ultimately be launched.”

Siqueira has a long history with NASA projects. Prior to his 2012 project, NASA’s Earth Science Technology Office had asked researchers at the UMass Amherst to participate in building a satellite-borne instrument that would allow scientists to forecast weather and climate changes with unprecedented accuracy. Siqueira was the principal investigator on that team, whose task was building an interferometric receiver to measure the “topography” and temperatures of Earth’s waters and give us unparalleled insights into the dynamics of our global climate.

Before coming to UMass in 2005, Siqueira was at the NASA Jet Propulsion Laboratory in Pasadena, California, where he worked on the engineering of airborne and space-borne microwave remote sensing systems and their application to earth sciences. Among many important projects he worked on were NASA’s Shuttle Radar Topography Mission and the Japanese Aerospace Exploration Agency’s Global 2 Rainforest Mapping Project.

Read NASA press release:

RELEASE 14-266

U.S., India to Collaborate on Mars Exploration, Earth-Observing Mission

In a meeting Tuesday in Toronto, NASA Administrator Charles Bolden and K. Radhakrishnan, chairman of the Indian Space Research Organisation (ISRO), signed two documents to launch a NASA-ISRO satellite mission to observe Earth and establish a pathway for future joint missions to explore Mars.

While attending the International Astronautical Congress, the two space agency leaders met to discuss and sign a charter that establishes a NASA-ISRO Mars Working Group to investigate enhanced cooperation between the two countries in Mars exploration. They also signed an international agreement that defines how the two agencies will work together on the NASA-ISRO Synthetic Aperture Radar (NISAR) mission, targeted to launch in 2020.

“The signing of these two documents reflects the strong commitment NASA and ISRO have to advancing science and improving life on Earth,” said NASA Administrator Charles Bolden. “This partnership will yield tangible benefits to both our countries and the world.”

The joint Mars Working Group will seek to identify and implement scientific, programmatic and technological goals that NASA and ISRO have in common regarding Mars exploration. The group will meet once a year to plan cooperative activities, including potential NASA-ISRO cooperation on future missions to Mars.

Both agencies have newly arrived spacecraft in Mars orbit. NASA’s Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft arrived at Mars Sept. 21. MAVEN is the first spacecraft dedicated to exploring the tenuous upper atmosphere of Mars. ISRO’s Mars Orbiter Mission (MOM), India’s first spacecraft launched to Mars, arrived Sept. 23 to study the Martian surface and atmosphere and demonstrate technologies needed for interplanetary missions.

One of the working group’s objectives will be to explore potential coordinated observations and science analysis between MAVEN and MOM, as well as other current and future Mars missions.

“NASA and Indian scientists have a long history of collaboration in space science,” said John Grunsfeld, NASA associate administrator for science. “These new agreements between NASA and ISRO in Earth science and Mars exploration will significantly strengthen our ties and the science that we will be able to produce as a result.”

The joint NISAR Earth-observing mission will make global measurements of the causes and consequences of land surface changes. Potential areas of research include ecosystem disturbances, ice sheet collapse and natural hazards. The NISAR mission is optimized to measure subtle changes of the Earth’s surface associated with motions of the crust and ice surfaces. NISAR will improve our understanding of key impacts of climate change and advance our knowledge of natural hazards.

NISAR will be the first satellite mission to use two different radar frequencies (L-band and S-band) to measure changes in our planet’s surface less than a centimeter across. This allows the mission to observe a wide range of changes, from the flow rates of glaciers and ice sheets to the dynamics of earthquakes and volcanoes.

Under the terms of the new agreement, NASA will provide the mission’s L-band synthetic aperture radar (SAR), a high-rate communication subsystem for science data, GPS receivers, a solid state recorder, and a payload data subsystem. ISRO will provide the spacecraft bus, an S-band SAR, and the launch vehicle and associated launch services.

NASA had been studying concepts for a SAR mission in response to the National Academy of Science’s decadal survey of the agency’s Earth science program in 2007. The agency developed a partnership with ISRO that led to this joint mission. The partnership with India has been key to enabling many of the mission’s science objectives.

NASA’s contribution to NISAR is being managed and implemented by the agency's Jet Propulsion Laboratory (JPL) in Pasadena, California.

NASA and ISRO have been cooperating under the terms of a framework agreement signed in 2008. This cooperation includes a variety of activities in space sciences such as two NASA payloads -- the Mini-Synthetic Aperture Radar (Mini-SAR) and the Moon Mineralogy Mapper -- on ISRO’s Chandrayaan-1 mission to the moon in 2008. During the operational phase of this mission, the Mini-SAR instrument detected ice deposits near the moon’s northern pole. (October 2014)

For more information on NASA’s Mars exploration program, visit:

For more information on the NISAR mission, visit: