A Year in Space for the CubeSat Multispectral Observing System: CUMULOS

CUMULOS is a three-camera system flying as a secondary payload on the Integrated Solar Array and Reflectarray Antenna (ISARA) mission with the goals of researching the use of uncooled commercial infrared cameras for Earth remote sensing and demonstrating unique nighttime remote sensing capabilities. Three separate cameras comprise the CUMULOS payload: 1) a visible (VIS) Si CMOS camera, 2) a shortwave infrared (SWIR) InGaAs camera, and 3) a longwave infrared (LWIR) vanadium oxide microbolometer. This paper reviews on-orbit operations during the past year, in-space calibration observations and techniques, and Earth remote sensing highlights from the first year of space operations. CUMULOS operations commenced on 8 June 2018 following the successful completion of the primary ISARA mission. Some of the unique contributions from the CUMULOS payloads include: 1) demonstrating the use of bright stars for on-orbit radiometric calibration of CubeSat payloads, 2) acquisition of science-quality nighttime lights data at 130-m resolution, and 3) operating the first simple Earth observing infrared payloads successfully flown on a CubeSat. Sample remote sensing results include images of: cities at night, ship lights (including fishing vessels), oil industry gas flares, serious wildfires, volcanic activity, and daytime and nighttime clouds. The CUMULOS VIS camera has measured calibrated nightlights imagery of major cities such as Los Angeles, Singapore, Shanghai, Tokyo, Kuwait City, Abu Dhabi, Jeddah, Istanbul, and London at more than 5x the resolution of VIIRS. The utility of these data for measuring light pollution, and mapping urban growth and infrastructure development at higher resolution than VIIRS is being studied, with an emphasis placed on Los Angeles. The Carr , Camp and Woolsey fires from the 2018 California fire season were imaged with all three cameras and results highlight the excellent wildfire imaging performance that can be achieved by small sensors. The SWIR camera has exhibited extreme sensitivity to flare and fire hotspots, and was even capable of detecting airglow-illuminated nighttime cloud structures by taking advantage of the strong OH emissions within its 0.9-1.7 micron bandpass. The LWIR microbolometer has proven successful at providing cloud context imagery for our nightlights mapping experiments, can detect very large fires and the brightest flare hotspots, and can also image terrain temperature variation and urban heat islands at 300-m resolution. CUMULOS capabilities show the potential of CubeSats and small sensors to perform several VIIRS-like nighttime mission areas in which wide area coverage can be traded for greater resolution over a smaller field of view. The sensor has been used in collaboration with VIIRS researchers to explore these mission areas and side-by-side results will be presented illustrating the capabilities as well as the limitations of small aperture LEO CubeSat systems

CubeSat Laser Communication Crosslink Pointing Demonstration

An opportunity arose to demonstrate optical crosslink pointing between two CubeSats in LEO using spacecraft not specifically designed for that purpose. The AeroCube-7 spacecraft, designed for optical downlinks as part of the Optical Communication and Sensor Demonstration mission, was tasked to point its communications laser at the ISARA spacecraft to demonstrate the capability of one CubeSat to track another in LEO. The ISARA spacecraft, which does not carry a data receiver, but does carry a short-wave infrared camera (SWIR) as part of the CUMULOS payload, was tasked to track the AeroCube-7 spacecraft and use the SWIR camera to record the OCSD laser. The SWIR images were downloaded over an RF channel and used to evaluate the pointing and tracking of both spacecraft. Two successful tests of crosslink pointing were completed between AeroCube-7 and ISARA, providing a demonstration in principle of the capability, and laying the groundwork for more refined experiments that will use this technique for on-orbit measurements of beam profiling. Further tests between AeroCube-11 and ISARA are also in preparation to demonstrate crosslink pointing in a more-challenging orbital configuration

Refractory Materials for Flame Deflector Protection System Corrosion Control: Coatings Systems Literature Survey

When space vehicles are launched, extreme heat, exhaust, and chemicals are produced and these form a very aggressive exposure environment at the launch complex. The facilities in the launch complex are exposed to this aggressive environment. The vehicle exhaust directly impacts the flame deflectors, making these systems very susceptible to high wear and potential failure. A project was formulated to develop or identify new materials or systems such that the wear and/or damage to the flame deflector system, as a result of the severe environmental exposure conditions during launches, can be mitigated. This report provides a survey of potential protective coatings for the refractory concrete lining on the steel base structure on the flame deflectors at Kennedy Space Center (KSC)

Landsat Imagery from a CubeSat: Results and Operational Lessons from the R3 Satellite\u27s First 18 Months in Space

R3 is a 3-U CubeSat launched on a RocketLab Electron into a 500 km circular orbit at 85° inclination on December 16th, 2018. The spacecraft flies a multispectral sensor that takes data in the six Landsat visible and near infrared bands. The R3 sensor mates a custom refractive telescope with a Materion Precision Optics Landsat filter, and an ON Semiconductor fast-framing high-sensitivity Si CMOS array, to produce 50-km wide, 44-m resolution Landsat-like image strips. Data are taken in push-broom mode and are downlinked via a 100Mbps compact lasercom system. Frames are then co-added on the ground in time-delay-integration (TDI) fashion to increase signal-to-noise ratio and create multi-spectral Earth images from the compact sensor. The system is an engineering concept demonstration of a compact multispectral sensor in CubeSat form. We describe our ConOps, flight operations, sensor focus and alignment, initial imaging check out, and initial comparisons of R3 data to Landsat-8 imagery of the same Earth locations. RGB, color infrared, and normalized differential vegetation index (NDVI) products are compared between CUMULOS and Landsat-8. Results show good multispectral image quality from the CubeSat sensor, and illustrate the ability of R3 to detect vegetation and other features in a manner similar to Landsat, as well as the challenge in perfectly exposing all 6 VIS/NIR Landsat bands using our commercial 10-bit CMOS array. We also highlight the performance of the compact laser communications system which enabled the successful performance of this mission

Molecular beam growth of graphene nanocrystals on dielectric substrates

We demonstrate the growth of graphene nanocrystals by molecular beam methods that employ a solid carbon source, and that can be used on a diverse class of large area dielectric substrates. Characterization by Raman and Near Edge X-ray Absorption Fine Structure spectroscopies reveal a sp2 hybridized hexagonal carbon lattice in the nanocrystals. Lower growth rates favor the formation of higher quality, larger size multi-layer graphene crystallites on all investigated substrates. The surface morphology is determined by the roughness of the underlying substrate and graphitic monolayer steps are observed by ambient scanning tunneling microscopy.Comment: Accepted in Carbon; Discussion section added; 20 pages, 6 figures (1 updated

Dynamics of entanglement for coherent excitonic states in a system of two coupled quantum dots and cavity QED

The dynamics of the entanglement for coherent excitonic states in the system of two coupled large semiconductor quantum dots ($R/a_{B}\gg 1$) mediated by a single-mode cavity field is investigated. Maximally entangled coherent excitonic states can be generated by cavity field initially prepared in odd coherent state. The entanglement of the excitonic coherent states between two dots reaches maximum when no photon is detected in the cavity. The effects of the zero-temperature environment on the entanglement of excitonic coherent state are also studied using the concurrence for two subsystems of the excitonsComment: 7 pages, 6 figure

Book Reviews: Spring 2020

Book Reviews, of:Dalsgaard (ed) – Thomas Pynchon in ContextChetwynd, Freer, Maragos (eds) – Thomas Pynchon, Sex, and GenderMogultay – The Ruins of Urban Modernity: Thomas Pynchon's Against the DayAlworth – Site Reading: Fiction, Art, Social FormMullins – Postmodernism in Pieces: Materializing the SocialHenry – New Media and the Transformation of Postmodern American Literature: From Cage to Connectionden Dulk – Existentialist Engagement in Wallace, Eggers, and Foer: A Philosophical Analysis of Contemporary American LiteratureAnderson – Postmodern Artistry in Medievalist Fiction: An International StudyHouser – Ecosickness in Contemporary U.S. Fiction: Environment and AffectPalleau-Papin (ed) – Under Fire; William T. Vollmann, The Rifles: A Critical Study [a note from the Book Reviews Editor: if you're interested in reviewing a book on any aspect of unconventional post-1945 US literature, please send an email proposing a review to [email protected]

Delegation and coordination with multiple threshold public goods: experimental evidence

When multiple charities, social programs and community projects simultaneously vie for funding, donors risk mis-coordinating their contributions leading to an inefficient distribution of funding across projects. Community chests and other intermediary organizations facilitate coordination among donors and reduce such risks. To study this, we extend a threshold public goods framework to allow donors to contribute through an intermediary rather than directly to the public goods. Through a series of experiments, we show that the presence of an intermediary increases public good success and subjects’ earnings only when the intermediary is formally committed to direct donations to socially beneficial goods. Without such a restriction, the presence of an intermediary has a negative impact, complicating the donation environment, decreasing contributions and public good success.When multiple charities, social programs and community projects simultaneously vie for funding, donors risk mis-coordinating their contributions leading to an inefficient distribution of funding across projects. Community chests and other intermediary organizations facilitate coordination among donors and reduce such risks. To study this, we extend a threshold public goods framework to allow donors to contribute through an intermediary rather than directly to the public goods. Through a series of experiments, we show that the presence of an intermediary increases public good success and subjects’ earnings only when the intermediary is formally committed to direct donations to socially beneficial goods. Without such a restriction, the presence of an intermediary has a negative impact, complicating the donation environment, decreasing contributions and public good success

Non–housestaff medicine services in academic centers: Models and challenges

Non–housestaff medicine services are growing rapidly in academic medical centers (AMCs), partly driven by efforts to comply with resident duty hour restrictions. Hospitalists have emerged as a solution to providing these services given their commitment to delivering efficient and high-quality care and the field's rapid growth. However, limited evidence is available on designing these services, including the similarities and differences of existing ones. We describe non–housestaff medicine services at 5 AMCs in order to share our experiences and outline important considerations in service development. We discuss common challenges in building and sustaining these models along with local institutional factors that affect decision making. Keys to success include ensuring an equitable system for scheduling and staffing, fostering opportunities for scholarly activities and academic promotion (defining the “academic hospitalist”), and providing compensation that supports recruitment and retention of hospitalists. With further work hour restrictions expected in the future and increased requests for surgical comanagement, the relationship between AMCs and hospitalists will continue to evolve. To succeed in developing hospitalist faculty who follow long careers in hospital medicine, academic leadership must carefully plan for and evaluate the methods of providing these clinical services while expanding on our academic mission. Journal of Hospital Medicine 2008;3:247–255. © 2008 Society of Hospital Medicine.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/60235/1/311_ftp.pd

Genome modeling system: A knowledge management platform for genomics

In this work, we present the Genome Modeling System (GMS), an analysis information management system capable of executing automated genome analysis pipelines at a massive scale. The GMS framework provides detailed tracking of samples and data coupled with reliable and repeatable analysis pipelines. The GMS also serves as a platform for bioinformatics development, allowing a large team to collaborate on data analysis, or an individual researcher to leverage the work of others effectively within its data management system. Rather than separating ad-hoc analysis from rigorous, reproducible pipelines, the GMS promotes systematic integration between the two. As a demonstration of the GMS, we performed an integrated analysis of whole genome, exome and transcriptome sequencing data from a breast cancer cell line (HCC1395) and matched lymphoblastoid line (HCC1395BL). These data are available for users to test the software, complete tutorials and develop novel GMS pipeline configurations. The GMS is available at https://github.com/genome/gms