Annual Highlights of Results from the International Space Station October 1, 2017 - October 1, 2018

The International Space Station (ISS) is a unique place a convergence of science, technology and human innovation that demonstrates new technologies and makes research breakthroughs that cannot be accomplished on Earth. As an international laboratory for scientific research in microgravity, the space stations international crew lives and works while traveling at a speed of about five miles per second as they make new discoveries in the disciplines of biology and biotechnology, Earth and space science, human research, physical science, educational activities, and technology development and demonstrations

User requirements for monitoring the evolution of stratospheric ozone at high vertical resolution (‘Operoz’: Operational ozone observations using limb geometry)

The purpose of the Operoz study has been threefold: (i) To establish the user requirements for an operational mission targeting ozone profiles at high vertical resolution, (ii) To identify the observational gaps with respect to these user requirements taking into account planned operational missions and observational ground networks, and (iii) To perform a reality check on the observational requirements based on proven concepts and present-day knowledge of potentially available measurement techniques and to identify options for a small to medium size satellite mission

Syöttöjärjestelmien suunnittelu hologrammiin perustuviin kompakteihin antennimittauspaikkoihin

A designing method for feed systems for hologram-based compact antenna test ranges (CATR) is developed. A hologram-based CATR can be used to test large antennas at millimetre and submillimetre wavelengths. Feed systems are used to provide a modified illumination for the hologram. Using the modified illumination from a feed system, narrow slots can be avoided in the hologram pattern. Narrow slots are difficult to manufacture accurately and limit the polarisation properties of the hologram.Feed systems use two shaped reflector or lens surfaces to shape the radiation pattern of a feed horn. The shaped surfaces are calculated with a ray-tracing based synthesis method and iteratively optimised based on simulation results. This synthesis method was previously used to design a 310 GHz dual reflector feed system (DRFS). In this work a 650 GHz DRFS is designed as part of large antenna measurement campaign in which a large antenna was tested in a hologram-based compact antenna test range. The DRFS is measured by near-field scanning with a planar scanner at 650 GHz. The measured amplitude ripple is about 0.8 dB peak-to-peak and the phase ripple is about 15° peak-to-peak. These measurements prove that no significant design or manufacturing errors were made.The feed system design and synthesis method has been extended also for feed systems based on shaped dielectric lenses. A dual lens feed system design example is designed, with same design goals as those with the 650 GHz DRFS. The design example proves that the synthesis method can be used also for feed systems based on shaped lenses.In this thesis, the designing method for feed systems based on either shaped reflector or lenses is presented. A 650 GHz DRFS is designed, tested, and used in a hologram-based CATR.Tässä työssä kehitetään syöttöjärjestelmien suunnittelumenetelmä hologrammiin perustuviin kompakteihin antennimittauspaikkoihin. Hologrammiin perustuvaa antennimittauspaikkaa voidaan käyttää suurten antennien testaamiseen millimetri- ja alimillimetriaaltoalueella. Syöttöjärjestelmiä käytetään muotoillun valaisun aikaan saamiseksi hologrammille. Kun käytetään muotoiltua valaisua voidaan välttää kapeat raot hologrammissa. Kapeat raot ovat vaikeita valmistaa tarkasti ja rajoittavat hologrammin polarisaatio-ominaisuuksia.Syöttöjärjestelmässä käytetään kahta muotoiltua heijastin- tai linssipintaa syöttötorven säteilykuvion muokkaamiseen. Muotollut pinnat lasketaan säteenseurantaan perustuvalla synteesimenetelmällä ja optimoidaan iteratiivisesti simulaatiotulosten perusteella. Tätä synteesimenetelmää on aiemmin käytetty kaksiheijastimisen syöttöjärjestelmän suunnitteluun 310 GHz:lle. Tässä työssä kaksiheijastiminen syöttöjärjestelmä suunnitellaan 650 GHz:lle osana isoa antennimittaus kampanjaa, jossa mitataan suurikokoinen antenni hologrammiin perustuvassa anitennimittauspaikassa. Suunniteltu syöttöjärjestelmä mitataan planaarisella lähikenttämittauksella 650 GHz:n taajuudella. Mitattu amplitudivaihtelu on 0,8 dB huipusta huippuun ja vaihevaihtelu on noin 15° huipusta huippuun. Mittaukset osoittavat, että merkittäviä suunnittelu- tai valmistusvirheitä ei ole tehty.Syöttöjärjestelmäsuunnittelu ja synteesimenetelmä yleistetään myös dielektrisiin linsseihin perustuville syöttöjärjestelmille. Kaksilinssinen syöttöjärjestelmä suunnitellaan samoilla suunnittelutavoitteilla kuin 650 GHz:n kaksiheijastiminen syöttöjärjestelmä. Tämä suunnitelu esimerkki todistaa, että kyseistä suunnittelu- menetelmää voi käyttää myös linsseihin perustuvien syöttöjärjestelmien suunnitteluun.Tässä työssä esitetään suunnittelumenetelmä muotoiltuihin linsseihin tai heijastimiin perustuville syöttöjärjestelmille. Kaksiheijastiminen syöttöjärjestelmä suunnitellaan, testataan ja sitä käytetään antennimittauksissa hologrammiin perustuvassa antenni-mittauspaikassa

Proceedings of the 2011 Space Cryogenics Workshop: "Poised for the Future, Reflecting on the Past"

The 24th Space Cryogenics Workshop was held at the Best Western Coeur d Alene Inn and Conference Center, Coeur d Alene, Idaho, June 8-10, 2011. The workshop was organized and sponsored by NASA Kennedy Space Center and NASA Marshall Space Flight Center, with a theme of "Poised for the Future, Reflecting on the Past." Over 100 scientists and engineers from around the world came together to discuss space applications for cryogenics, renew old acquaintances, and meet new practitioners in the field of space cryogenics

Status of the Global Observing System for Climate

Status of the Global Observing System for Climat

Radiative Effect of Mixed Mineral Dust and Biomass Burning Aerosol in the Thermal Infrared

This thesis treats the optical properties of mixed mineral dust and biomass burning aerosol in the thermal infrared (TIR) based on Fourier Transform infrared spectrometer (FTIR) measurements and radiative transfer simulations. The measurements were part of the Saharan Mineral Dust Experiment 2 (SAMUM-2) conducted from January to February 2008 at Praia, Cape Verde. The large amount of different instruments co-located at the main field site during the campaign resulted in a unique dataset comprising in-situ information and remote sensing data perfectly suited for column closure studies. The ultimate goal of this work is to investigate the consistency of microphysical and TIR remote sensing data. This is achieved by reproducing the measured radiances at top and bottom of the atmosphere (TOA, BOA) with a radiative transfer model, which assimilates the microphysical aerosol information gathered during SAMUM-2. The first part of the thesis describes several experimental efforts, including a novel calibration method and a drift correction algorithm for the ground-based FTIR instrument operated within the scope of SAMUM-2 by the author. The second part introduces the concurrent radiative transfer library PIRATES, which has been developed in the framework of this thesis for the analysis of TIR aerosol optical properties. The third and final part of the treatise compares measured and simulated spectra for various typical scenarios encountered during SAMUM-2. It is demonstrated in three case studies, that measured radiances in the TIR atmospheric window region (8-12 µm) can be reproduced at BOA and TOA by radiative transfer simulations assuming spheroidal model particles. Moreover, spherical particles are shown to be an inadequate model for mineral dust aerosol in this spectral region unless the aerosol optical depth is small