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Observation of Pc 3/5 Magnetic Pulsations Around the Cusp at Mid Altitude
1 OBSERVATION OF PC 3/5 MAGNETIC PULSATIONS AROUND THE CUSP AT MID ALTITUDE Liu Yonghua(1), Liu Ruiyuan(1), B. J. Fraser(2), S. T. Ables(2), Xu Zhonghua(1), Zhang Beichen(1), Shi Jiankui(3), Liu Zhenxing(3), Huang Dehong(1), Hu Zejun(1), Chen Zhuotian(1), Wang Xiao(3), Malcolm Dunlop(4), A. Balogh(5) (1) Polar Research Institute of China, 451 Jinqiao Rd., Shanghai 200136, P. R. CHINA, [email protected] (2) The University of Newcastle, University Drive, Callaghan NSW 2308, AUSTRALIA, [email protected] (3)The Center of Space Science & Applied Research, Chinese Academy of Science, Post Box8701, Beijing 100080, jkshi@@center.cssar.ac.cn (4) The Rutherford Appleton Laboratory, Chilton, DIDCOT, Oxfordshire, OX11 0QX, UK, [email protected] (5)Space and Atmospheric Physics Group, Imperial College, London, [email protected] ABSTRACT transmitted straightforwardly from solar wind to the ionosphere (Bolshakova & Troitskaia, 1984). So far most Since launched in year 2000 the Cluster mission has research work on such topic are on basis of observation passed the region around the cusp at mid-altitude (~6Re) at ground or/and data from satellite located in the for many times, where ULF wave activities are rich in. upstream of solar wind or in the magnetosheath. To my From 0800 to 1300UT on October 30 2002 the Cluster knowledge, few authors take a study based on the spacecrafts ran along an orbit of southern cusp- measurement at the mid-altitude of the cusp. It seems plasmasphere-northern cusp that provides an excellent reasonable to assume that such a measurement be a direct observation of ULF waves in dayside magnetosphere. -
Planned Yet Uncontrolled Re-Entries of the Cluster-Ii Spacecraft
PLANNED YET UNCONTROLLED RE-ENTRIES OF THE CLUSTER-II SPACECRAFT Stijn Lemmens(1), Klaus Merz(1), Quirin Funke(1) , Benoit Bonvoisin(2), Stefan Löhle(3), Henrik Simon(1) (1) European Space Agency, Space Debris Office, Robert-Bosch-Straße 5, 64293 Darmstadt, Germany, Email:[email protected] (2) European Space Agency, Materials & Processes Section, Keplerlaan 1, 2201 AZ Noordwijk, Netherlands (3) Universität Stuttgart, Institut für Raumfahrtsysteme, Pfaffenwaldring 29, 70569 Stuttgart, Germany ABSTRACT investigate the physical connection between the Sun and Earth. Flying in a tetrahedral formation, the four After an in-depth mission analysis review the European spacecraft collect detailed data on small-scale changes Space Agency’s (ESA) four Cluster II spacecraft in near-Earth space and the interaction between the performed manoeuvres during 2015 aimed at ensuring a charged particles of the solar wind and Earth's re-entry for all of them between 2024 and 2027. This atmosphere. In order to explore the magnetosphere was done to contain any debris from the re-entry event Cluster II spacecraft occupy HEOs with initial near- to southern latitudes and hence minimise the risk for polar with orbital period of 57 hours at a perigee altitude people on ground, which was enabled by the relative of 19 000 km and apogee altitude of 119 000 km. The stability of the orbit under third body perturbations. four spacecraft have a cylindrical shape completed by Small differences in the highly eccentric orbits of the four long flagpole antennas. The diameter of the four spacecraft will lead to various different spacecraft is 2.9 m with a height of 1.3 m. -
ASTRONOMY and ASTROPHYSICS Seismology of Δ Scuti Stars in the Praesepe Cluster II
Astron. Astrophys. 338, 511–520 (1998) ASTRONOMY AND ASTROPHYSICS Seismology of δ Scuti stars in the Praesepe cluster II. Identification of radial modes and their associated stellar parameters M.M. Hernandez´ 1?,F.Perez´ Hernandez´ 1, E. Michel2, J.A. Belmonte1, M.J. Goupil2, and Y. Lebreton2 1 Instituto de Astrof´ısica de Canarias, E-38200 La Laguna, Tenerife, Spain 2 DASGAL, URA CNRS 335, Observatoire de Paris, F-92195 Meudon, France Received 5 January 1998 / Accepted 20 July 1998 Abstract. An analysis based on a comparison between obser- Several attempts have been made to obtain stellar informa- vations and stellar models has been carried out to identify radial tion from δ Scuti stars (e.g. Mangeney et al. 1991; Goupil et modes of oscillations in several multi-periodic δ Scuti stars of al. 1993; Perez´ Hernandez´ et al. 1995; Guzik & Bradley 1995). the Praesepe cluster (BU, BN, BW and BS Cnc). The assump- All have had to face the absence of the greater part of the the- tion that all the stars considered have common parameters, such oretical modes in the observed spectrum. Noise level, selection as metallicity, distance or age, is imposed as a constraint. Even mechanisms, geometrical effects and also mutual interference so, there is a large number of possible solutions, partially caused between very close modes (as recently illustrated by Belmonte by the rotational effects on the pulsation frequencies and on the et al. 1997) contribute towards explaining this phenomenon. stars’ positions in the HR diagram, which need to be parame- Even in the case of a large number of detected modes, such as terized. -
European Space Agency Announces Contest to Name the Cluster Quartet
European Space Agency Announces Contest to Name the Cluster Quartet. 1. Contest rules The European Space Agency (ESA) is launching a public competition to find the most suitable names for its four Cluster II space weather satellites. The quartet, which are currently known as flight models 5, 6, 7 and 8, are scheduled for launch from Baikonur Space Centre in Kazakhstan in June and July 2000. Professor Roger Bonnet, ESA Director of Science Programme, announced the competition for the first time to the European Delegations on the occasion of the Science Programme Committee (SPC) meeting held in Paris on 21-22 February 2000. The competition is open to people of all the ESA member states. Each entry should include a set of FOUR names (places, people, or things from his- tory, mythology, or fiction, but NOT living persons). Contestants should also describe in a few sentences why their chosen names would be appropriate for the four Cluster II satellites. The winners will be those which are considered most suitable and relevant for the Cluster II mission. The names must not have been used before on space missions by ESA, other space organizations or individual countries. One winning entry per country will be selected to go to the Finals of the competition. The prize for each national winner will be an invitation to attend the first Cluster II launch event in mid-June 2000 with their family (4 persons) in a 3-day trip (including excursions to tourist sites) to one of these ESA establishments: ESRIN (near Rome, Italy): winners from France, Ireland, United King- dom, Belgium. -
Baseplate Variability of Vibrio Cholerae Chemoreceptor Arrays
Baseplate variability of Vibrio cholerae chemoreceptor arrays Wen Yanga,1, Alejandra Alvaradob,1, Timo Glatterc, Simon Ringgaardb,2, and Ariane Briegela,2 aInstitute of Biology, Leiden University, 2333 BE Leiden, The Netherlands; bDepartment of Ecophysiology, Max Plank Institute for Terrestrial Microbiology, 35043 Marburg, Germany; and cCore Facility for Mass Spectrometry and Proteomics, Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany Edited by John S. Parkinson, University of Utah, Salt Lake City, UT, and accepted by Editorial Board Member Caroline S. Harwood November 12, 2018 (received for review July 11, 2018) The chemoreceptor array, a remarkably ordered supramolecular these, clusters I and III are expressed only under certain growth complex, is composed of hexagonally packed trimers of receptor conditions (low oxygen and as a general stress response, respectively) dimers networked by a histidine kinase and one or more coupling (16–18). The proteins from cluster I form cytoplasmic arrays, in proteins. Even though the receptor packing is universal among which two baseplate layers sandwich cytosolic chemoreceptors and chemotactic bacteria and archaea, the array architecture has been are stabilized by a specialized receptor with two signaling domains extensively studied only in selected model organisms. Here, we (19, 20). Cluster III is structurally not well understood at present. show that even in the complete absence of the kinase, the cluster II Neither of these systems has been implicated in canonical che- arrays in Vibrio cholerae retain their native spatial localization and motactic behavior, and their cellular function remains elusive. In the iconic hexagonal packing of the receptors with 12-nm spacing. contrast, cluster II has been shown to be responsible for chemo- Our results demonstrate that the chemotaxis array is versatile in tactic behavior under all tested conditions so far (21). -
China Dream, Space Dream: China's Progress in Space Technologies and Implications for the United States
China Dream, Space Dream 中国梦,航天梦China’s Progress in Space Technologies and Implications for the United States A report prepared for the U.S.-China Economic and Security Review Commission Kevin Pollpeter Eric Anderson Jordan Wilson Fan Yang Acknowledgements: The authors would like to thank Dr. Patrick Besha and Dr. Scott Pace for reviewing a previous draft of this report. They would also like to thank Lynne Bush and Bret Silvis for their master editing skills. Of course, any errors or omissions are the fault of authors. Disclaimer: This research report was prepared at the request of the Commission to support its deliberations. Posting of the report to the Commission's website is intended to promote greater public understanding of the issues addressed by the Commission in its ongoing assessment of U.S.-China economic relations and their implications for U.S. security, as mandated by Public Law 106-398 and Public Law 108-7. However, it does not necessarily imply an endorsement by the Commission or any individual Commissioner of the views or conclusions expressed in this commissioned research report. CONTENTS Acronyms ......................................................................................................................................... i Executive Summary ....................................................................................................................... iii Introduction ................................................................................................................................... 1 -
Orbit Aspects of End-Of-Life Disposal from Highly Eccentric Orbits K. Merz(1)
Orbit Aspects of End-Of-Life Disposal from Highly Eccentric Orbits K. Merz(1)(2), H. Krag(1), S. Lemmens(1), Q. Funke(3), S. Böttger(4), D. Sieg(5), G. Ziegler(5), A. Vasconcelos(5), B. Sousa(1), H.-J. Volpp(6), R. Southworth(1) (1)ESA/ESOC, Robert-Bosch-Str. 5, 64293 Darmstadt, Germany, (2) ESA/ESOC, +49-6151-90-2990, [email protected] (3) IMS SPACE CONSULTANCY GMBH c/o ESA/ESOC, (4) Luleå University of Technology, Luleå, Sweden (5) SCISYS Deutschland GmbH c/o ESA/ESOC, (6) ESA/ESOC, retired Abstract: End-of-Life disposal options are well established for missions in the Low Earth Orbit (LEO) and Geostationary Orbit (GEO) regions and consist, respectively, of near circular graveyard orbits or atmospheric decay. Science missions such as ESA’s Integral and Cluster-II missions, however, sometimes operate on highly-eccentric Earth orbits (HEO) to achieve their mission goals, such as astronomical observations or measurements of the Earth's environment. The dominant perturbation forces on these orbits are typically caused by the gravity fields of Sun and Moon. This paper highlights ESA's investigations on orbit manoeuvres to change the long- term evolution and to finally influence the orbital lifetime, re-entry epoch, and re-entry location for the Cluster-II and Integral spacecraft. Manoeuvres, years before the end of the mission, to target a safe natural re-entry driven by third body perturbations several years after the end of mission, were analysed and implemented. The manoeuvre options considered are presented with a view to their cost in delta-v and therefore maximum post-manoeuvre operational lifetime and their effect on orbital lifetime and re-entry location. -
Giove-A Spacecraft (Galileo in Orbit Validation Element), the First European Navigation Satellite
SOYUZ TO LAUNCH GALILEO This new Starsem’s flight will boost the European Space Agency’s Giove-A spacecraft (Galileo In Orbit Validation Element), the first European navigation satellite. This prestigious mission constitutes the 15th Starsem flight. Starsem’s close cooperation with the European Space Agency started in 2000, as the European-Russian venture successfully delivered the 4 Cluster-II scientific satellites, using similar ver- sions of the Soyuz launch vehicle. Then in June 2003, Starsem has successfully launched the European Space Agency’s Mars Express interplanetary probe to the Red Planet, starting the first European mission to Mars. Following this success, on November 9, 2005, Starsem precisely injected into the intended liberation orbit the European Space Agency’s Venus Express spacecraft, a replica of its Mars explora- tion predecessor. The purpose of flight ST15 is to inject the 602 kg Giove-A spa- cecraft on the Middle Earth Orbit (MEO) of the final Galileo satellite constellation, to characterise the orbit environment and transmit the navigation signals at all the frequencies plan- ned for the Galileo constellation for securing the frequency allocation and enable early experimentation on ground. Visit us on www.starsem.com 1 MISSION DESCRIPTION The launch of Giove-A will be performed from the Baikonur Cosmodrome, Launch Pad #6. The Giove-A launch slot is fixed from December 6, 2005 to March 6, 2006. The launch is possible at any day inside the above launch slot. On December 26, 2005, the launch time will be 05:19 a.m. UTC: 11:19 a.m. Baikonur time 08:19 a.m. -
Cluster Approach Evaluation 2 Synthesis Report
IASC CLUSTER APPROACH EVALUATION, 2ND PHASE APRIL 2010 Cluster Approach Evaluation 2 Synthesis Report Julia Steets, François Grünewald, Andrea Binder, Véronique de Geoffroy, Domitille Kauffmann, Susanna Krüger, Claudia Meier and Bonaventure Sokpoh 2 Disclaimer The opinions expressed in this report are those of the authors and do not necessarily represent those of the members / standing invitees of the Inter-Agency Standing Committee. Acknowledgments The evaluation team would like to thank all those who have provided their support and input to this evaluation. We are particularly grateful for the excellent and constructive guidance and support from the evaluation management team of Claude Hilfiker and Andreas Schütz, the constructive inputs and feedback from the evaluation steering group, the wisdom and advice of the members of our advisory group, the great support from OCHA country offices, and the willingness of all those many individuals in the six case study countries and at the global level to provide their time and insights through interviews, their participation in the survey or group discussions and their feedback on earlier versions of the synthesis and country reports. Our thoughts are particularly with those who supported our evaluation mission to Haiti, many of whom were deeply affected by the earthquake of January 12, 2010. 3 Table of contents Acronyms. 5 Executive Summary . 8 1 Introduction . .17 2 Method. 19 2.1 Overall approach. 19 2.2 Scope of the evaluation. 20 2.3 Limits of the evaluation. 21 2.4 Organization of the evaluation and quality management. .24 3 Background. 24 3.1 Humanitarian reform and the cluster approach. -
Arxiv:2001.03626V1 [Astro-Ph.GA] 10 Jan 2020 Max Planck Institute for Astronomy K¨Onigstuhl17, 69121 Heidelberg, Germany E-Mail: [email protected] A
The Astronomy and Astrophysics Review (2020) Nuclear star clusters Nadine Neumayer · Anil Seth · Torsten B¨oker Received: date / Accepted: date Abstract We review the current knowledge about nuclear star clusters (NSCs), the spectacularly dense and massive assemblies of stars found at the centers of most galaxies. Recent observational and theoretical work suggest that many NSC properties, including their masses, densities, and stellar populations vary with the properties of their host galaxies. Understanding the formation, growth, and ultimate fate of NSCs therefore is crucial for a complete picture of galaxy evolution. Throughout the review, we attempt to combine and distill the available evidence into a coherent picture of NSC 9 evolution. Combined, this evidence points to a clear transition mass in galaxies of 10 M where the characteristics of nuclear star clusters change. We argue that at lower masses, NSCs∼ are formed primarily from globular clusters that inspiral into the center of the galaxy, while at higher masses, star formation within the nucleus forms the bulk of the NSC. We also discuss the coexistence of NSCs and central black holes, and how their growth may be linked. The extreme densities of NSCs and their interaction with massive black holes lead to a wide range of unique phenomena including tidal disruption and gravitational wave events. Lastly, we review the evidence that many NSCs end up in the halos of massive galaxies stripped of the stars that surrounded them, thus providing valuable tracers of the galaxies' accretion histories. Contents 1 Introduction . .2 2 Early studies . .4 2.1 Imaging nuclear star clusters: the Hubble Space Telescope . -
A European Perspective on Uranus Mission Architectures
A European perspective on Uranus mission architectures Chris Arridge1,2 1. Mullard Space Science Laboratory, UCL, UK. 2. The Centre for Planetary Sciences at UCL/Birkbeck, UK. Twitter: @chrisarridge Ice Giants Workshop – JHU Applied Physics Laboratory, MD, USA – 30 July 2014 2/32 Overview of the Cosmic Vision • Originated with Horizon and Horizon+ programmes. – Missions born from that programme include Mars Express, Venus Express, ROSETTA, HERSCHEL, Huygens, HST. • Cosmic Vision driven by scientific themes: 1. What are the conditions for planetary formation and the emergence of life? 2. How does the Solar System work? 3. What are the physical fundamental laws of the Universe? 4. How did the Universe originate and what is it made of? • Part of ESA’s mandatory programme – contributions from member states weighted by GDP, • Operate according to a set of guidelines that broadly-speaking demand a programmatic balance (between scientific domains) and due return. 3/32 Overview of the Cosmic Vision • Originated with Horizon and Horizon+ programmes. – Missions born from that programme include Mars Express, Venus Express, ROSETTA, HERSCHEL, Huygens, HST. • Cosmic Vision driven by scientific themes: 1. What are the conditions for planetary formation and the emergence of life? 2. How does the Solar System work? 3. What are the physical fundamental laws of the Universe? 4. How did the Universe originate and what is it made of? • Part of ESA’s mandatory programme – contributions from member states weighted by GDP, • Operate according to a set of guidelines that broadly-speaking demand a programmatic balance (between scientific domains) and due return. 4/32 Mission classes • Medium “M”-class: 500 M€ - example Solar Orbiter. -
Cancer Cells Retrace a Stepwise Differentiation Program During Malignant Progression
Author Manuscript Published OnlineFirst on April 28, 2021; DOI: 10.1158/2159-8290.CD-20-1637 Author manuscripts have been peer reviewed and accepted for publication but have not yet been edited. Cancer cells retrace a stepwise differentiation program during malignant progression Sadegh Saghafinia 1,2,3,#, Krisztian Homicsko 1, Annunziata Di Domenico 4, Stephan Wullschleger 1,+, Aurel Perren 4, Ilaria Marinoni 4, Giovanni Ciriello 2,3, Iacovos P. Michael 1,$,#,*, and Douglas Hanahan 1,5,* 1 Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland 2 Department of Computational Biology, University of Lausanne (UNIL), Lausanne, Switzerland 3 Swiss Institute of Bioinformatics (SIB) 4 Institute of Pathology, University of Bern, Bern, Switzerland 5 Lausanne Branch, Ludwig Institute for Cancer Research, Lausanne, Switzerland + Current address: Molecular Partners AG, Zurich, Switzerland $ Current address: Biological Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada # These authors contributed equally * Corresponding authors: [email protected], [email protected] Running Title Retracing stepwise differentiation during tumor progression Keywords Pancreatic Neuroendocrine tumor, Dedifferentiation, Cancer plasticity, Tumor heterogeneity, Metastasis, miRNA-181, Hmgb3, Meis2 Corresponding Authors contact details: Iacovos P. Michael, Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada | Phone: 416-480-6100x3354