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Satellite instrument change in orbit during a mission lifetime can result in significant error for absolute radiance sensor calibrations. Polarization (POL) response, out-of-band signal rejection (OOB), and relative spectral response (RSR) are important contributors to understanding calibration error, yet no existing systems can conduct all of these diagnostics while a sensor is in space. In this presentation, a system under development is described that enables new diagnostic analyses of radiometers while they are in orbit by propagating a laser beam from the ground. While the system is not expected to provide high accuracy (

The Goddard Laser for Absolute Measurement of Radiance (GLAMR) has been used to provide spectral and radiometric calibration data for several earth science instruments, including the Joint Polar Satellite System (JPSS) -2 and -3 Visible and Infrared Radiometer Suite (VIIRS). Analysis of data collected by both VIIRS instruments has suggested the presence of fluorescence emitted from the GLAMR integrating sphere when illuminated by visible and ultraviolet light. This takes the form of an unexpected out of band response below 550 nm in several VIIRS bands that is in addition to interband electronic crosstalk. The VIIRS spectral response is also characterized by a monochromator which does not replicate the higher out-of-band response but has reduced dynamic range. As a result of the VIIRS data analysis, additional characterization of the GLAMR integrating sphere have been performed specifically to check for fluorescence in the visible and near infrared range by illuminating the sphere with visible and near ultraviolet monochromatic light. The broad band spectrum of radiance generated by the integrating sphere is measured using a calibrated spectroradiometer at 3 nm spectral resolution with high SNR at a factor of 10-4 of the radiance of the primary illumination wavelength. This allows for out of band characterization down to the noise floor of previous VIIRS testing. This spectrum is correlated with the VIIRS data sets as well as other instruments calibrated using the same integrating sphere. Prior instrument data also allows some check of the stability of the fluorescence signal over time. The characterization of the fluorescence will allow it to be accounted for in analysis of flight instrument spectral responses and improve the overall accuracy of the GLAMR characterization.

Additional file 1 Figure S1. Genome-wide association plot with the phenotypic sex for each Stirling and GIFT family from BSA-ddRAD analysis. Each dot represents a SNP and the Y-axis represents the magnitude of association (−log10P value of F-test) of the SNP with phenotypic sex, while the X-axis represents the position in the linkage groups of the assembled Nile tilapia genome. The alternating blue and green colours are used to distinguish between chromosomes. The red solid line represents a q-value of 0.05 and the blue solid line represents a q-value of 0.01.

The Operational Land Imager (OLI) 2 is the visible, near-infrared and short-wave infrared sensor to be flown on Landsat 9. It is nearly identical to the OLI on Landsat 8. Several improvements to the pre-launch characterization program were implemented for OLI 2, including a revised instrument level spectral response test. This characterization used the NASA Goddard Laser for Absolute Measurement of Radiance (GLAMR), in lieu of the traditional monochromatorbased system used for the Landsat 8 OLI. GLAMR, like the system on which it was based, the NIST Spectral Irradiance and Radiance responsivity Calibrations using Uniform Sources (SIRCUS), uses tunable lasers coupled into an integrating sphere with a large exit port. The GLAMR based test provided characterization of 100% of the OLI 2 detectors spectral response with the OLI 2 full aperture and about 5° of the field illuminated as opposed to about 10% of the OLI detectors using partial aperture illumination of about 0.15° of the field illuminated with the monochromator-based system. Testing was performed across the full spectral range of the sensitivity of the OLI 2 detectors, approximately 350 to 2500 nm. This enhanced testing captured some variation in the spectral response within individual focal plane modules related to spectral filter transmission variations and expected variations in spectral response across the focal plane due to angle of incidence and different filter wafers used for the focal plane modules. In addition, with illumination of adjacent focal plane modules, most cross talk effects were appropriately captured. The measured spectral responses met the requirements in the vast majority of cases with a few minor deviations.

In December 2014, NIST’s laser-based Traveling SIRCUS calibration system was installed at Raytheon SAS in El Segundo, CA for testing of the NOAA/NASA Joint Polar Satellite System-1 (JPSS-1) VIIRS sensor’s visible and near-infrared bands. The tunable laser sources were installed in the ante-room outside the Raytheon clean room where the VIIRS sensor was located. The output from the tunable lasers was fiber-coupled into a 1-m diameter Spectralon integrating sphere source positioned in front of the VIIRS sensor’s Earth-view port and VIIRS Absolute Spectral Responsivity (ASR) measurements were made. In a second configuration, a polarizer was placed between the source and the VIIRS entrance port and polarization sensitivity testing was done. In this work, we present details of the T-SIRCUS calibration system, including a new automated tunable Optical Parametric Oscillator (OPO) system, achievable radiances with the 1-m Spectralon integrating sphere, and an uncertainty budget for the integrating sphere radiance. An approach to extend the dynamic range of out-of-band measurements using a recently develop Flat Plate Illuminator will be introduced. Finally, VIIRS sensor ASR and polarization responsivity results and implications based on the measurements are discussed.

The species flocks of cichlid fishes in the Great East African Lakes are paradigms of adaptive radiation and hence, of great interest to evolutionary biologists. Phylogenetic studies of these fishes have, however, been hampered by the lack of suitable polymorphic markers. The genes of the major histocompatibility complex hold the promise to provide, through their extensive polymorphism, a large number of such markers, but their use has been hampered by the complexity of the genetic system and the lack of definition of the individual loci. In this study we take the first substantial step to alleviate this problem. Using a combination of methods, including the typing of single sperm cells, gyno- or androgenetic individuals, and haploid embryos, as well as sequencing of class II B restriction fragments isolated from gels for Southern blots, we identify the previously characterized homology groups as distinct loci. At least 17 polymorphic class II B loci, all of which are presumably transcribed, have been found among the different species studied. Most of these loci are shared across the various cichlid species and genera. The number of loci per haplotype varies from individual to individual, ranging from 1 to 13. A total of 21 distinct haplotypes differing in the number of loci they carry has thus far been identified. All the polymorphic loci are part of the same cluster in which, however, distances between at least some of the loci (as indicated by recombination frequencies) are relatively large. Both the individual loci and the haplotypes can now be used to study phylogenetic relationships among the members of the species flocks and the mode in which speciation occurs during adaptive radiation.