国际虚拟天文台研究进展 崔辰州 China-VO项目组 中国科学院国家天文台 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

报告内容 虚拟天文台产生的时代背景 虚拟天文台研究历史回顾 国际虚拟天文台联盟（IVOA） VO标准简介 各国VO项目研发亮点 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

天文数据的爆炸性增长 1 microSky (DPOSS) 1 nanoSky (HDF-S) Multi-Terabyte (soon: multi-Petabyte) sky surveys and archives over a broad range of wavelengths 1 microSky (DPOSS) Billions of detected sources, hundreds of measured attributes per source 1 nanoSky (HDF-S) 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

观测天文学面临的挑战 Large digital sky surveys are becoming the dominant source of data in astronomy: > 100 TB, growing rapidly Current examples: SDSS, 2MASS, DPOSS, GSC, FIRST, NVSS, RASS, IRAS; CMBR experiments; Microlensing experiments; NEAT, LONEOS, and other searches for Solar system objects … Digital libraries: ADS, astro-ph, NED, CDS, NSSDC Observatory archives: HST, CXO, space and ground-based Future: QUEST2, LSST, and other synoptic surveys; GALEX, SIRTF, astrometric missions, GW detectors Data sets orders of magnitude larger and more complex than in the past Roughly 1 TB/Sky/band/epoch (1 arcsec pixels, 1 byte per pixel) 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

科学的变革 数千年前: 经验的科学 描述自然现象 几百年前: 理论性科学 引入模型概念，概括与分析 数十年前: 计算科学 模拟复杂现象 数千年前: 经验的科学 描述自然现象 几百年前: 理论性科学 引入模型概念，概括与分析 数十年前: 计算科学 模拟复杂现象 今天: 数据探索 (e-Science) 理论、试验、模拟的统一 数据管理、统计分析 仪器收集数据，程序模拟数据 利用软件分析 科学分析、数据挖掘 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

从量变到质变 统计天文学 可观测参数空间的系统性分析探索 精确宇宙学、星系结构、恒星天体物理 Discovery of significant patterns and multivariate correlations 统计误差不再重要 可观测参数空间的系统性分析探索 Searches for rare or unknown types of objects and phenomena Low surface brightness universe, the time domain Confronting massive numerical simulations with massive data sets 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

精确宇宙学：理论与观测的更好结合 DPOSS clusters Numerical simulation 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

全波段宇宙学 …reveals a more complete physical picture The resulting complexity of data translates into increased demands for data analysis, visualization, and understanding 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

multi-l views of a Supernova Remnant Shocks seen in the X-ray Dust seen in the IR Heavy elements seen in the optical Relativistic electrons seen in the radio

时域分析 Megaflares on normal main sequence stars (DPOSS) 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

时域分析 Faint, Fast Transients 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

宇宙演化模拟 芝加哥大学宇宙物理中心 IBM RS/6000 (National Energy Research Scientific Computing Center, NERSC) Origin2000 (National Center for Supercomputing Applications, NCSA) 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

VO的第一个科学发现 通过对X射线和光学数据的联合处理发现了68个2型AGN候选体， 在GOODS区找出40个被光学掩盖了的2型类星体，9个为已知，31个为新发现。 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

VO历史回顾 1990s:NASA成立了按波长划分的科学数据中心，多个地基数字巡天项目开始 1999年4月, 美国理论、计算和数据发现十年规划调研专家组成立 Szalay, Prince, Alcock 提出 “National Virtual Observatory”的概念 1999年11月, NVO 在JHU组织研讨会 2000年2月, 第二届 NVO 研讨会在NOAO召开 2000年6月, “Virtual Observatories of the Future”在Caltech召开，褚耀泉参加会议 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

VO历史回顾 2001年2月, “新千年的天文学与天体物理学”发表 2001年9月, 美国NSF 宣布对NVO项目的资助 2001年9月，第一次中国虚拟天文台研讨会召开 2002年6月，国际虚拟天文台联盟成立 2002年7月，中国虚拟天文台概念提出 2002年10月，中国虚拟天文台成为IVOA成员 2003年7月，China-VO首次参加IVOA的面对面执委会会议 2003年9月，第二次中国虚拟天文台研讨会召开 2004年12月1-5，第三次中国虚拟天文台研讨会正在举行 2005年秋，4th China-VO workshop? 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

“虚拟天文台”的定义 Euro-VO: A Virtual Observatory (VO) is a collection of interoperating data archives and software tools which utilize the internet to form a scientific research environment in which astronomical research programs can be conducted. 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

What the Virtual Observatory is… Andy What the Virtual Observatory is… A suite of international standards for the discovery, exchange, intercomparison, and analysis of network-accessible astronomical data A data access and analysis environment that exploits the emerging computation/software/data Grid A framework for data processing that enables and encourages the re-use of algorithms A tool for science planning: Identify gaps in coverage of parameter space. Which new missions, instruments, experiments will have largest impact? A catalyst for world-wide access to astronomical archives A routinely used tool of the research astronomer A vehicle for education and public outreach 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

What the Virtual Observatory is not… Andy What the Virtual Observatory is not… A replacement for building new telescopes and instruments A centralized repository for data A data quality enforcement organization 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

虚拟天文台 Web：all docs in the world inside your PC VO：all databases in the world inside your PC 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

VO 的基本要素 Andy standards inter-operable data inter-operable software modules no central VO-command 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

The VO Vision US-VO http://us-vo.org The VO is the “semantic web” for astronomy The VO democratizes astronomical research The VO brings the universe to your desktop The professional astronomer Graduate students Undergraduates K-12 Amateurs The public http://us-vo.org 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

我的理解 虚拟天文台 通过先进的信息技术把世界范围内的研究资源无缝透明联结起来组成的数据密集型在线天文研究环境 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

我的理解 虚拟天文台 通过先进的信息技术把世界范围内的研究资源无缝透明联结起来组成的数据密集型在线天文研究环境 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

国际虚拟天文台联盟（IVOA） http://www.ivoa.net 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

International VO Alliance 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

International VO Alliance The IVOA brings together the astronomers, developers, and managers of the VO initiatives world-wide Agreements on standards for data access (VOTable, catalog queries, image retrieval, resource descriptions, etc.) Coordination of development activities Sharing of software Sharing of experience 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Differences among projects Big project Small Project Scale (Members, Institutes, Funding) large small Activity high low R&D focus Framework and standards Application and tools - Just in my personal opinion 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Activity Statistics - Incomplete, Just in my personal opinion 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Status of VO projects 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

AVO-> Euro-VO AVO: ended on Oct 31, 2004 Euro-VO kickoff meeting: Nov. 18-19 led by Euro-VO Exec (Quinn, Genova, Lawrence) VO-Tech:Jan 1st 2005 3.3M euros over 3 year 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Bridging IVO Standards ~ Best Practice Best Practices As resources, tools It is important for the IVOA standards and recommendations to be learned and adopted by astronomers/users. As references and guides It is important for VO developers and data providers 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Small project is suitable for the role Familiar to IVOA standards With required IT/CS backgrounds (Grid, WS, XML, SOAP, etc.) Know well astronomer requirements 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Bridging IVOA ~ Domestic Community Common tasks for small projects to contribute domestic data archives and expertise to the world to share international data, tools with international partners for domestic research and education a “gateway” between domestic and world wide resources 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

认识VO标准 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

International VO Alliance 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

VOTable Reached international agreement on VOTable V1.0 specification in April 2002 XML-based standard with in-line data or links to external data Utilized for basic catalog and image access protocols Merges “AstroRes” heritage with XML flexibility Complements FITS Multiple I/O libraries available (Java, Perl, C++, C#) 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Data Models Data modeling effort aimed at defining basic data types and relationships among them High-level entities: image, spectrum, time series, catalog Low-level entries: quantity, resolution, time of observation Interfaces and protocols for other VO services derived from DM relationships 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

SSA Data Model Sampled spectrophotometric sequence A SED is: Summary projected at constant time results in 1D spectrum projected at constant spectral value results in time series projecting both results in a photometry point A SED is: a collection of these three types of objects at a constant point on the sky (usually!) typically spanning a wide range of spectral values Summary a SED attempts to describe the full spectral energy distribution of an object, encompassing as much of the emitted energy as possible 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

SED Segments a,b: 测光点 c: 4个时刻的时序数据 d: 上限测量 e:简单光谱 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Data Access Layer Data Access Layer is mediator between VO data requests and data delivery Defined “Cone Search” protocol and have ~100 implementations Defined Simple Image Access Protocol (SIAP) and have 20+ implementations OpenSkyQuery provides database interface to OpenSkyNodes with extended SQL-like VO Query Language Specification for Simple Spectral Access Protocol in development 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Resource Metadata and Registry Resource Metadata describes VO data collections, services; this metadata is collected into a Registry Resource Identifiers are component of resource metadata; have agreed on syntax Using Open Archive Initiative protocols for metadata harvesting Now focusing on query mechanisms and general updating/synching options Prototype registry utilized in science demonstration, Data Inventory Service 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Unified Content Descriptors UCDs provide common data dictionary for describing contents of catalogs CDS initiative, now broadened to international VO discussion Current discussion focusing on structure and extensibility 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

VO Query Language Working on minimal extensions to SQL to support astronomical queries (e.g., spatial proximity)  Astronomical Data Query Language Defining standard query service based on SDSS SkyQuery: OpenSkyNode and OpenSkyQuery Investigating higher-level query languages; natural language Xquery 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Grid and Web Services Increasing number of web services (cone search and SIAP wrappers, for example) Registry services will be implemented as web services Prototyped use of Grid in galaxy morphology science demonstration ROME (Remote Object Management Environment) project provides stateful user interface to Grid-based or other compute-intensive applications Working closely with Grid community to understand progress on Grid services, e.g., OGSA, and to determine best time to adopt 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

DAL Services Dataset Time Series Table Source Catalog Event List Visibility Data Image NDImage 1D Spectrum SED 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Simple Image Access (SIA) Provides access to "image" data (instead of spectrum, catalog, etc.) regularly sampled (pixelated) data generally an image of the sky, with a WCS Service-oriented data discovery query service to discover data Access to image metadata can get image metadata without retrieving the actual image uniform description based on standard data models Access to image datasets data may be virtual or computed on demand uniform interface to any type of image data 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Simple Spectral Access Provides access to "spectral" data similar to SIA but deals with tabular spectrophotometric data Service-oriented data discovery query service to discover data Access to dataset metadata can get dataset metadata without retrieving actual dataset uniform interface based on standard data models Access to actual dataset data may be virtual, i.e., computed on demand uniform interface to any type of spectral data hides details of how data is stored or represented externally 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

各国VO研发采风 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Data Inventory Service: NVO DataScope Scientific Motivation: Rapid collection of multi-wavelength imaging, catalog and observation data following an interesting transient event is essential. This service can also be used as a general tool to quickly access all data available on any patch of sky for any science use.   Data Resources: Multi-wavelength data from any number of sites (currently 13 different sites) sampling energies from X-ray to radio, and including images, object lists, and catalogues of observations. What the VO Brings: Integration and organization of a variety of data sources into an easily comprehensible information set. Scalability to an arbitrary number of data providers. Integrates data with multiple data visualization services.   Enabling Technologies: Standard protocols to remote services such as Cone Search and Simple Image Access, standardized VOTables for data retrieval transformation, and standardized semantics encoded as Uniform Content Descriptors (UCDs). Resource registry.   Future Prospects: Customization and quality control of resources searched; more sophisticated use of metadata. Positions of HST and Chandra observations for GRB010222 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Data Inventory Service 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Data Inventory Service 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Data Inventory Service 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Spectral Database Browser 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Spectral Database Browser 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Spectral Database Browser 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Spectral Database Browser 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

VOSpec: Interoperable Tool SIMBAD Web Service Registry Access VOTable standard 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

JVO SkyNode Architecture Apache Axis and Tomcat are used for implementing the VO standard interface, and Globus Toolkit is used for an optional Grid interface. Four kinds of query languages are converted to java class SelectSQL and query is executed through JDBC-like interface. Query results is obtained as ResultSet, and table data is formatted to VOTable or CSV file. JVO Portal Internet JVO SkyNode JVOQL Grid GTK 3 (optional) SelectSQL Translator Query Executer Formatter JDBC for SkyNode JVO SkyNode DBMS JVOQL ADQL-x HTTP/SOAP AXIS ResultSet getMetadata() getString() getFits() getJpeg() SIAP SSAP HTTP/Parameter Tomcat 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

VOPlot3D: Sample Scatter Plot 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Aus-VO: Visualization system A software system that allows scientists to view and analyse astronomical data that are stored in remote locations. RVS Server User Data Centre User connects to view data Visualisation Data (Image) sent to user RVS response Dataset sent to RVS Browse data 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Glu sites 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

2004年6月3日版IVOA路线图 Done. Demo 05 Freeze Current Architecture Roadmap V1 SIA V1.0 Architecture RSM V1.0 UCD V1.0 VOTable V1.0 Spectrum Access V0.9 Observation Data Model V0.9 VOTable V1.1 Registry Interface V0.9 Image Access V1.1 UCD V1+ Roadmap V2 ADQL + SkyNode V0.9 Web Service V0.5 MySpace + MyDB + SRB VOSpace Workflow not yet subject to standardization progress on IVOA standard documents 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

2005及以后发展规划 VOQL 1.0 ‘05 Full registry specification 1.0 ‘05 Single sign on 1.0 ‘05 VOSpace 1.0 ‘05?? Work flow 1.0 ‘06 Web Services Interfaces 1.0(inc logging) ‘05 Data Model plans (Registries - VOResource) ‘05 VOList 0.5 ‘05? Ontology (semantics) ‘05-> Simulation data (services) milestone’05

2005及以后发展规划（续） Preservation 1.0 ‘06 ??? January 2005 Coordinated complex demo July 2005 Data Centre take-up workshop and evaluation January 2006 Data Centre Interoperability Coordinated demo IAU August 2006 Data Centre take-up statistics (July 05, July 06) Reference implementations January 2006 Implementations feedback July 2006 VO-enable science metric August 2006 IAU January 2007 Community Applications in action? (Jan’05, Jan’06) 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3

Thank You Q & A ? www. .org 第三届中国虚拟天文台研讨会☆武汉☆2004.12.1-3