The New York Space Grant News

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1 The New York Space Grant News Newsletter of the New York NASA Space Grant Consortium Fall 2007 Supporting education and research in space-related fields through fellowships, internships, outreach, and corporate partnerships New York NASA Space Grant Consortium Lead Institution: Cornell University Affiliates: Barnard College City College of New York, CUNY Clarkson University Colgate University Columbia University Lockheed Martin Manhattan College Medgar Evers College, CUNY Polytechnic University Rensselaer Polytechnic Institute Sciencenter SUNY Buffalo SUNY Geneseo SUNY Stony Brook Syracuse University York College, CUNY Greetings The primary objectives of the New York Space Grant are to encourage and enhance educational programs in science, technology, engineering, and math (STEM) through undergraduate and graduate fellowships and scholarships, research opportunities, teacher training, K- 12 outreach, and public education. Though reaching out to New York State s population of 19 million is daunting, the Space Grant works hard to include diverse people in our various programs. The New York Space Grant is fortunate to count many dedicated affiliates among its consortium. These affiliates stretch across the state, from Rennselaer Polytechnic Institute in Troy to SUNY Buffalo, and from Clarkson University in Potsdam to multiple colleges in the New York City area. This year we are proud to welcome SUNY Stony Brook as a new affiliate. We plan to work closely with the SUNY Louis Stokes Alliance for Minority Participation Program, headed by Prof. David Ferguson at Stony Brook, to attract and retain under-represented minority students in STEM disciplines. Graduate and undergraduate research is an important aspect of our program. In offering students time and support to develop their own ideas and theories, we are nurturing the future scientific and technologic workforce. Many of the students we assist are quite likely to become leaders in NASA s workforce and in society at large. In this newsletter you will read about the progress of numerous Space Grant-supported programs. It is clear that whether they are launching rockets or high altitude balloons, or manufacturing nanosatellites, our students are excited about the prospect of future work at NASA. Yervant Terzian Director

2 CCNY Students Design a Portable Biomonitor for NASA Eleven City College of New York (CCNY) juniors volunteered in fall 2006 for an independent study course to design a biomonitor to help assess astronaut health during spaceflight. The students were supervised by Prof. Luis Cardoso and two teaching assistants. This project was funded by the NASA Exploration Systems Mission Directorate (ESMD) Space Grant higher education program. Astronauts are exposed to harsh environments with many factors that pose threats to their health and well-being. In particular, long-term spaceflight and reduced gravity conditions have been shown to impair cardiac, muscular, and neurological (disturbed sleep cycle) functions. Continuous monitoring of certain physiological parameters can help detect acute and chronic medical conditions that adversely affect the astronauts and may result in mission failure. The goal of this project was to develop a minimally invasive, portable biomonitor to measure several vital parameters related to heart, brain, and muscle activity, as well as measure blood oxygen saturation and radiation exposure. To ensure the monitor is safe to wear and minimally invasive, numerous design specifications had to be met, including Worst-case failure poses no electrical risk to the astronaut or the spacecraft. Robust enough to be worn during physical activities such as exercise or research tasks. Utilize a telemetry system with external storage capability for recording biosignals. Minimize device s susceptibility to, and production of, electromagnetic interference. Audio and visual alarms announce when a measured parameter reaches a dangerous level. Testing the biomonitor prototype. Eight of the design team students with Prof. Cardoso. The eleven team members were: A. Larriera and C. Hue (team leaders), L. Davis, B. Javed, N. Khouma, A. Latif, M. Osman, P. Shah, S. Singh, Y. Teklehaimanot, and J. Tindi. The biomonitor prototype constructed by the students consists of five acquisition channels with signal conditioning for three types of biopotentials (electrocardiography, electroencephalography, and electromyography) plus oxygen saturation and radiation exposure sensors. Blood oxygen saturation is measured by computing the absorption ratio between red and infrared light transmitted across the blood vessels in the thumb. Radiation exposure is assessed using infrared/ultraviolet photo diodes to generate a voltage proportional to the IR/ UV radiation in the environment. The heart of the system is the microcontroller, which controls the biomonitor operation and determines if any abnormal conditions have occurred. A built-in liquid crystal display (LCD) shows measured numerical values, while continuous waves can be transmitted wirelessly, via Bluetooth technology, to a computer for data display and storage. This one-semester biomedical engineering design project was very enriching for the students. It provided an opportunity to integrate their engineering and medical knowledge to solve real-world challenges for NASA. The students proposed that this project be continued for one more year, as part of their senior capstone design course in biomedical engineering. The device size and weight will be further minimized and powered with a rechargeable New York Space Grant 2

3 battery and solar cells. The software will be further enhanced to post-process signals to analyze derived parameters such as heart rate, heart rate variability, and muscle strength. The circuits will be fabricated on a printed circuit board. The device will be enclosed within a small plastic case containing the LCD display, keypad, and buzzer. Ultimately the final biomonitor will be worn on an astronaut s upper arm. Luis Cardoso and Sheldon Weinbaum City College of New York, CUNY New York, NY Example electrocardiogram (EKG) waveform measured with the biomonitor prototype. New York Student Delegates Travel to Spain for SGC and IAC Kathleen Coderre (Rennselaer Polytechnic Institute) and Frank Centinello (SUNY Buffalo) were selected to attend the 2006 Space Generation Congress (SGC) and the 57th International Astronautical Congress (IAC). The conferences were held consecutively September 28 through October 6 in Valencia, Spain. The New York Space Grant provided funds to defray some of the students travel expenses. The conferences brought together students, young professionals, and aerospace industry leaders from around the world to discuss and create recommendations for global space activities. At the SGC, Kathleen participated in the Space Education Working Group which explored ways to expand space education in schools on an international level. Frank participated in the Space Technology Development Working Group which discussed technologies to make humanity a space-faring civilization and ways to spread space-related technology to underdeveloped countries. Kathleen received the Jim and Lin Burke Young Pioneer Award at the SGC for exhibiting great leadership and enthusiasm at the conference. Since then, Kathleen has graduated from Rennselaer with a BS in Aeronautical and Mechanical Engineering. Employed by Lockheed Martin in Houston, TX, she works on the Orion Crew Exploration Vehicle. Frank continues his graduate studies at SUNY Buffalo. He helped start a Students for the Exploration of Space (SEDS) chapter at Buffalo, and is a project leader for the 2007 SGC. Kathleen Coderre with NASA Administrator Mike Griffin at IAC. Frank Centinello with a European Space Agency (ESA) Mars rover mockup at IAC. Fall 2007

4 N e w Yo r k Spac e Gra n t H i g h l i g h t s Clarkson University The Clarkson University Space Grant Program involved more than 14 undergraduates and two graduate students this year. This spring, Leighton M. Myers and Jonathan M. Holla presented a paper on helicopter research at the American Institute of Aeronautics and Astronautics student conference. During the summer, Myers interned at Lockheed Martin in Owego prior to entering graduate school at Purdue University. Ashley Macner, Jonathan M. Holla, and Frashad Madhi conducted research on waves and splashing phenomena, helicopters, and unsteady aerodynamics this summer. Supported by NASA Exploration Systems Mission Directorate (ESMD) Space Grant funding, Clarkson students participated in two national competitions during the academic year: the NASA Fundamental Aeronautics 2007 University Student Competition and Revolutionary Aerospace Systems Concepts Academic Linkage (RASC-AL) The Clarkson team undergraduates Myers and Holla and faculty advisors Piergiovanni Marzocca and Daniel T. Valentine was awarded Honorable Mention for its Clarkson University s RASC-AL 2007 team. Subsonic Rotary Wing Experiment entry in the NASA Fundamental Aeronautics 2007 competition. This highly competitive contest included undergraduate teams doing capstone design course projects and teams of all graduate students. Participating gave our students an opportunity to solve some of the technical challenges facing actual NASA aeronautics projects. RASC-AL, an initiative of NASA Langley Research Center and the Universities Space Research Association (USRA), was created to engage college students in devising revolutionary concepts and technologies leading to future NASA research opportunities. The principal activity of RASC-AL is an annual conference at which students present the results of their studies to peers and representatives from NASA and industry. The Clarkson team was among the top 10 teams selected, receiving additional funds from USRA to participate in the RASC-AL Forum 2007 held on May in Galveston, Texas. The team included students Wade E. Bartlett, Andrew T. Bingham, Stephen D. Caron, Myles M. Farrell, Robert T. Fievisohn, Sean D. Moore, Daniel N. Valyou, Kate M. Wickswat, and Robert A. Zilnicki and faculty advisors Piergiovanni Marzocca and Daniel T. Valentine. Their project, entitled Manned Missions to Near Earth Objects Using Exploration Systems Architecture Study Hardware, was recognized as very innovative. The RASC-AL team leader, Andrew T. Bingham, was also distinguished by a monetary award for outstanding scholarship and achievement at the Clarkson University commencement ceremony. His employment at NASA Jet Propulsion Laboratory began this summer. RASC-AL team members visit the Space Vehicle Mockup Facility at NASA Johnson Space Center. New York Space Grant

5 N e w Yo r k Spac e Gra n t H i g h l i g h t s SUNY Geneseo It has been another exciting year for astronomy and space physics at SUNY Geneseo. Last summer s research students presented their work at the American Astronomical Society winter meeting in Seattle. Prof. Aaron Steinhauer worked this summer with undergraduates Dan Gettings and Scott Ciampa on photometry projects of the open star clusters NGC 1817 and NGC 2423 to derive cluster ages, distances, and metallicities. Another student, Elise Jutzeler, tackled an infrared spectroscopic study of low-mass stars in the star forming region L988e to determine cluster age and identify brown dwarfs. All three accompanied Prof. Steinhauer on a three-night observing run on the WIYN 0.9m Telescope at Kitt Peak National Observatory in June. Dave Meisel, now Distinguished Professor Emeritus of Computational Astrophysics, continued work on Arecibo-observed micrometeors SUNY Geneseo students at Kitt Peak National Observatory. in collaboration with colleagues at the Communications and Space Sciences Laboratory at Penn State University, the Radiophysics Laboratory at Kazan State University in Russia, and the EISCAT radar in Kiruna, Sweden. He co-authored a number of papers presented at the Meteoroids 2007 conference in Barcelona, Spain and began collaboration on meteor detection with Brookhaven National Lab and SUNY Stony Brook. In the coming year, he will spearhead a renovation of the Samuel Goldstein, Jr. Radio Telescope, a very successful past Space Grant project at Geneseo. Undergraduate student Tyler Manee continued work with Prof. Ed Pogozelski on the autonomously guided parafoil. The goal of this project is to launch the system using a small weather balloon and have it return to a predetermined landing location. This summer the craft was upgraded with a propeller to enable progress towards its destination in a headwind. York College Keri Salvador presenting at the Jan American Astronomical Society meeting. This summer Keri Salvador conducted Space Grant-funded research to model the expected gamma-ray emission from starburst galaxies in preparation for the Gamma-ray Large Area Space Telescope (GLAST) mission. Starburst galaxies have enhanced radiation fields and gas densities in the nuclear starforming region as well as enhanced cosmic ray generation from copious supernovae. Gamma-ray emission from them is predicted to be high, yet has never been detected. With the sensitivity of GLAST, she predicts roughly a dozen detections from Cycle 1 of the mission and has been modeling the expected fluxes and spectra from starburst galaxies. Fall 2007

6 N e w Yo r k Spac e Gra n t H i g h l i g h t s Polytechnic University During the program year, Prof. Vikram Kapila and his students conducted several research and outreach activities with the support of the New York Space Grant. Their activities focused on advanced control technology for aerospace systems, mechatronics-related experiments, and pre-college outreach. In spring 2006 they conducted a handson Mechatronics Poly presentation/ demonstration at the Why Science, Technology and Invention are Fun for Youth/Minority Youth seminar in Harlem, New York. Prof. Kapila, doctoral student Hong Wong, and masters student Christopher Wilkins developed a novel scheme to deploy a CubeSat constellation. CubeSat is a low-cost, small spacecraft platform within a 4-inch (10 cm) cube with total mass less than 2.2 pounds (1 kg). To date, CubeSats have been used as demonstration spacecraft primarily for academic research purposes. This technology has the potential for widespread use as an economical means for distributed broadcasting. To do so effectively, CubeSats must be sparsely distributed around the Earth to yield the desired level of coverage. The current technology typically entails deploying a fleet of monolithic spacecraft one launch at a time, necessitating a substantial amount of resources each time. In contrast, a broadcasting platform based on CubeSat technology may be inexpensive to deploy as it may be possible to launch an entire platform with backups using only a small number of deployers. Each deployer spacecraft would contain its own supply of operational and additional CubeSats for mission redundancy. In recent research, Wong and Wilkins developed and analyzed a deployment scheme for a constellation of CubeSats. Coverage was restricted to the region within 60 N to 60 S latitude, with the insertion of one hundred CubeSats into low Earth orbit using two deployer spacecraft. The deployers were assumed to be moving in polar orbits and were tasked to insert CubeSats into other circular orbits around the Earth only by imparting a change in orbital inclination. To account for the substantial change in velocity needed for CubeSat orbital inclination adjustment, a proof-of-concept small, single-stage rocket propulsion system was outlined. Perturbations inherent in the dynamics of spacecraft in low Earth orbit were utilized as a timing mechanism to allow sparse spatial distribution of CubeSats around the Earth. A series of numerical simulations were performed to illustrate that sufficient and effective coverage can be achieved. Visit < for additional details. Syracuse University Syracuse University students, including a summer 2006 NASA Space Grant recipient, designed a revolutionary 2nd-generation flying-wing aircraft. The aircraft utilizes embedded Cross-Flow Fan (CFF) technology for distributed propulsion and flow control. In this concept, the CFF is placed near the trailing edge of the wing. Low energy air along the suction surface is drawn into the propulsor, energized by the fan, and expelled out the trailing edge to produce thrust. This design is unique in that it greatly delays flow separation earlier computational and experimental work has demonstrated it to work at a 40 angle-of-attack with lift coefficient on the order of 6. The integration of the propulsor and the wing, called a Propulsive-Wing, results in a high-lift configuration that may be used for short take-off and landing (STOL) applications or carrying considerably heavy internal payloads. New York Space Grant

7 N e w Yo r k Spac e Gra n t H i g h l i g h t s SUNY Buffalo At the University at Buffalo (UB) SUNY, Space Grant funds were used to support the five-week BEAM (Buffalo-area Engineering Awareness for Minorities) summer program. Thirteen eleventhgrade BEAM students attended mathematics, computer, and presentation skills classes Mondays through Thursdays. On Fridays they attended guest lectures and participated in field trips at educational and industrial locations, such as the Niagara Aerospace Museum, Mt. Morris Dam at Letchworth State Park, Cannon Design (an architectural and engineering services firm), and Calspan Corporation s flight research hangars. Two of the students participated in the BEAM/ School of Engineering and Applied Sciences (SEAS) Honors Research Program. Prof. Wayne Anderson and the New York Space Grant, UB/SEAS, and BEAM sponsored and funded this special program. Christopher Guerra worked with Prof. Harsh Chopra on exploring one-atom contacts. Such technology can be used to make a hard drive the size of a credit card hold an infinite amount of data. Maureen West learned to use Auto-CAD and Abacus software programs for her summer project with Prof. Cemal Basaran. During the school year the BEAM students worked on projects using Lego Mindstorms Robotics Buffalo-area Engineering Awareness for Minorities (BEAM) high school students. Invention Systems. They built and programmed a RoverBot robot in the fall semester, and built and programmed a robot based on their own original design in the spring semester. Space Grant funds were also used to support Peter Mersich, an Electrical Engineering research assistant working on thin film and nanowire silicon products, and fellowships for six UB students in Mechanical Engineering and Electrical Engineering, each of whom worked closely with a professor on an individual research project. The Propulsive-Wing aircraft will have a wing span of 4 feet (1.2 m) and is intended to carry bulk payloads up to 10 inches (25.4 cm) tall and 5 pounds (2.3 kg) in weight. Students are engaged in the project at many levels, including Computational Fluid Dynamics studies, wind-tunnel verification and data collection, manufacturing, and flight testing. Another Space Grant recipient developed methods for fabricating complicated aircraft parts from carbon fiber and completed construction of the Propulsive-Wing aircraft during summer Computer model depicting the revolutionary Propulsive-Wing aircraft. 7 Fall 2007

8 N e w Yo r k Spac e Gra n t H i g h l i g h t s Medgar Evers College The MECSAT High Altitude Balloon Program at Medgar Evers College, CUNY was featured in a New York Times video, Mapping Ozone. The video combined the ozonesonde launches, supported by the NASA Aura Education and Public Outreach program, and the student-based BalloonSATs which require payload tracking and recovery. The video is online and available through the NY Times Science video archives and on itunes as a podcast. MECSAT team members ready materials for an ozonesonde launch. The MECSAT program, funded in part by the New York Space Grant, has received additional equipment for ozonesonde launches and will be expanding with collaborations with two other minority institutions: University of Houston-Downtown and South Carolina State University. Visit the updated MECSAT web site < for more information. Medgar Evers student prepares the electrochemical concentration cell for the ozonesonde. National Rocket Contest for Middle and High School Students Photo credit: Joe Barron, Aerospace Industries Association Registration for Team America Rocketry Challenge (TARC), the world s largest rocket contest, begins September 5, This year s challenge is to design, build, and fly a one-stage model rocket carrying two raw eggs to an altitude of 750 feet (229 meters), keep it aloft for 45 seconds, and return it safely to the ground with the eggs unbroken. High school and middle school teams complete local qualifying flights, then the top 100 are invited to Washington, DC for the National Flyoff in May. Winners vie for $60,000 in scholarships and cash. The contest is open to all US schools and nonprofit youth organizations, and is sponsored by the Aerospace Industries Association, National Association of Rocketry, NASA, Department of Defense, and the American Association of Physics Teachers. Please visit < for more information and to sign up for the latest updates. New York Space Grant

9 2007 Central New York Rocket Team Challenge Fierce Competition in Withering Heat Mission Control data acquisition table, manned by Syracuse University and MOST staff. The hot air temperature at the Syracuse University launch site was nearly matched by the high turnout for the 2007 Central New York (CNY) Rocket Team Challenge. A total of 75 teams, twice as many as the previous year, assembled on the morning of Saturday, June 2. As the day warmed to the mid 90s, the table tops hosting rocket preparation and data acquisition heated to 120 degrees! Staff and volunteers from the Milton J. Rubenstein Museum of Science & Technology (MOST), LC Smith College of Engineering and Computer Science, College of Environmental Science and Forestry, and Lockheed Martin Corporation dealt with the heat, high humidity, and logistics of prepping and launching 75 rockets in a three-hour window approximately one launch every three minutes. Funded in part by Space Grant, this competition included two divisions: middle school (grades 4-8) and high school (grades 9-12). The five-student teams enrolled in the program in early February and attended informational meetings at MOST to learn Rocket Science 101, rocket design and construction, and rocket safety from Syracuse University and MOST staff. Each team received basic materials, rocket simulation software (RockSim by Apogee Components), and training to build a rocket capable of lifting an electronic payload with an eggstronaut to peak altitudes between 656 and 1312 feet (200 and 400 meters). Each rocket carried a video and audio acquisition device with real-time transmission back to the launch site as well as a high-speed digital altimeter to record the flight trajectory. Teams were judged in the following categories: 1. Rocket aesthetics, 2. Student presentation, incorporating relevant technical knowledge, 3. Successful flight, 4. Successful eggstronaut payload recovery, and 5. Precision in estimating the rocket s apogee. The two top teams proved their mastery of rocket science by correctly estimating the apogee of their rockets. The winning high school team (Nottingham HS, Syracuse City School District) was within one foot, and the winning middle school team (Whitesboro MS, Whitesboro City School District) was within four feet. Syracuse University faculty judged the event components and Lockheed Martin Corporation officials presented awards to the winning teams. All team members received certificates of participation and the three top teams in each division received school plaques. Results containing on-board video and telemetry data for each flight can be found at < Peter Plumley Milton J. Rubenstein Museum of Science & Technology (MOST) Syracuse, NY Nottingham High School student with his team s winning rocket. Fall 2007

10 CUSat Team Earns Free Launch of Nanosatellite into Space CUSat team members with advisor Prof. Mason Peck after winning the Nanosat-4 competition. Cornell s CUSat student team was chosen from among 11 other teams to build their spacecraft under the Nanosat-4 Program, earning them a free launch of their self-designed satellite into space. The University Nanosatellite Program, a joint program run by the US Air Force and the American Institute of Aeronautics and Astronautics, seeks to prepare the future aerospace workforce by providing college students hands-on experience with small satellite research and development, systems integration, and flight testing. CUSat was chosen for its design, robustness, and relevance to technologies and mission capabilities vital to NASA and the Air Force. Its mission is in-orbit inspection: a demonstration of how one spacecraft can evaluate the health status of another by imaging it during relative-navigation maneuvers. In October of 2009, the two identical, hexagonal satellites will launch as one 90-pound (41-kilogram) unit and then separate once in orbit. Flying approximately 10 yards (9 meters) apart, one satellite will take detailed photographs of the other in various orientations and relay the imagery to a ground station in Ithaca, NY. Either spacecraft is capable of serving as the primary. The imagery can then be reconstructed into 3-D models to represent the actual on-orbit satellite structure. Such extensive relative navigation and inspection capabilities are crucial for future real-time, on-orbit spacecraft operations to verify configuration and detect any damage or malfunctions. New technologies developed by Cornell faculty include Prof. Mark Psiaki s advanced Global Positioning System (GPS) algorithms to determine relative position accuracy within centimeters, and Prof. Mark Campbell s Teflon-burning pulsed-plasma thruster design. CUSat is completely student-run: student managers guide all aspects of the satellite development and manufacturing, and students spend countless hours outside of their coursework on the project. About 225 students have been involved since project inception. Currently there are approximately 80 Cornell students, both undergraduate and graduate, on the team. After two years of hard work creating, refining, and prototyping their satellite design, CUSat team members and advisor Prof. Mason Peck now look forward to the next stage of the program: getting the software and hardware ready for spaceflight. Their dedication is being rewarded in many ways, as Prof. Peck reports: Students have been heavily recruited by NASA and the aerospace industry. In many cases this opportunity has helped shaped their careers. The CUSat project has received funding from the New York and Maryland Space Grant Consortia for student support. Completing the satellites and getting them ready for launch will cost up to $400,000, and the team is seeking additional sponsors and funding for their remaining costs of about $100,000. For more information, visit the CUSat web site: < Mason Peck and Erica Miles Cornell University Ithaca, NY CUSat spacecraft layout, showing structure, electronics, cameras, thrusters, and solar panels. New York Space Grant 10

11 NYSG Undergraduate Student Internships: Summer 2007 Location Students Description Cornell University 7 Research in astronomy, biomedical engineering, mechanical & aerospace engineering, and earth & atmospheric sciences. NYSG affiliates 30 Research in numerous science and engineering disciplines. Lockheed Martin Systems Integration NASA centers 11 NASA academies 5 * NYSG interns funded by Lockheed Martin. 3 NYSG student internships in various engineering disciplines.* Science/engineering Space Grant and ESMD internships at: Jet Propulsion Laboratory Kennedy Space Center Langley Research Center Marshall Space Flight Center Internships with: NASA Academy at Ames Research Center NASA Academy at Goddard Space Flight Center NASA Academy at Marshall Space Flight Center NASA Robotics Academy at Ames Research Center Map of NY colleges attended by undergraduate summer interns NY county map from geology.com Photographs of the STS-117 Atlantis launch taken by Matthew Cannella, a NY Space Grant intern from SUNY Buffalo who worked at KSC this summer. 11 Fall 2007

12 New York Space Grant Affiliate Directors Prof. Yervant Terzian, Cornell University (Director) Prof. Wayne Anderson, SUNY Buffalo Prof. Shermane Austin, Medgar Evers College Prof. Thomas Balonek, Colgate University Prof. Edward Brown, Manhattan College Prof. Thong Dang, Syracuse University Dr. Denny Fallon, Lockheed Martin Middle school teachers from Queens and Brooklyn attended the Cornell Physical & Space Sciences Teacher Institute, which was partially funded by NY Space Grant. Prof. David Ferguson, SUNY Stony Brook Prof. David Helfand, Columbia University Prof. Vikram Kapila, Polytechnic University Prof. Reshmi Mukherjee, Barnard College Prof. Heidi Newberg, Rensselaer Polytechnic Institute Prof. Tim Paglione, York College Prof. Ed Pogozelski, SUNY Geneseo Prof. Charles Trautmann, Sciencenter Prof. Daniel Valentine, Clarkson University Prof. Sheldon Weinbaum, City College of New York Space Grant summer interns at Cornell. New York Space Grant Consortium 517 Space Sciences Building Cornell University Ithaca, NY New York Space Grant News Newsletter of the New York Space Grant Consortium Editors: Erica Miles Patricia Fernández de Castro Center for Radiophysics and Space Research Dept. of Astronomy and Space Sciences Cornell University