Subject: HVO report Date: Thursday, January 22, 2004 9:50 AM From: Istvan Csabai To: Peter Quinn Hungarian Virtual Observatory The goal of HVO is to coordinate the efforts of Hungarian researchers who are working on VO development. Our group is strongly interacting with the JHU team of NVO and with the SDSS project. RESULTS/PLANS: VO services We are developing services for the Virtual Observatory, mainly using the Web services technology. One of the recent developments is the Spectrum and filter service, which will be extended by Photometric redshift estimation and Synthetic spectrum service in the future. Data archives Hungary itself is not running major astronomical surveys but several Hungarian researchers are involved in the large international projects. The HVO site will hold the copies of several such projects to ease and accelerate the access of local scientists and reduce the load of other mirrors. One of the largest astronomical archives, the SDSS SkyServer will be the first survey, which we will put on our servers. The DR1 version with the brand new Hungarian translation will be made available in the beginning of 2004. We have plans also to make public, but "old fashioned" databases "VO ready". Up to now we have converted 2MASS, FIRST, INTWFS, IRAS, NVSS, PSCz, ROSAT, 2dF, 2QZ to be able to accessed from the common SkyQuery interface. Also we have plans to make VO ready the unique sunspot database at the Debrecen observatory. Public outreach, education Astronomy related science is traditionally popular for the general public also. This gives the possibility to use it in education and popular science, disseminating both the new scientific discoveries and the new computational technologies. We have a Hungarian government supported project that aims to create popular science material. This will include web based science projects from basic to advanced levels, and strongly interacting with the Science Projects pages of SkyServer. DETAILS: Spectrum service for the Virtual Observatory: (http://voservices.net/wave/) In this already working service, spectra of galaxies and other astronomical objects are accessible through Web services, and several manipulation/transformation can be made on them. These manipulations include creating the composite spectrum from spectra of several similar objects, calculating the brightness of the object at different cosmological distances, convolving spectra with filters, etc. All of these services are very useful for astronomers, and in the absence of this service, it would involve several steps to download the spectra, convert to a given format, write programs to calculate the desired physical property, etc. All of these steps are hidden, everything is automatic. We would like to add several new features and make substantial improvements. The service can return data in VOTable format. Synthetic spectrum service: The current database of the spectrum service contains 45GB of observed spectra mainly from the SDSS and 2dF surveys. As the number of observations increase, more and more knowledge accumulates about the physical properties of galaxies. Astrophysicists create galaxy spectrum models which are capable to simulate the star population evolution, dust content and other physical features. These computer models require a bunch of input parameters to specify the age and the type of the galaxy and returns the spectrum. These spectra could be compared to measurements, used in subsequent studies. The idea is to use the same interface (spectrum service) as for the observed spectra. This would make much easier the comparisons and spectrum manipulations, but this is not the biggest advantage. Currently if someone would like to use a spectral model, he has to find out which spectral synthesis code to use, download the source code, the libraries and struggle with compilation, etc. We plan to implement all the leading models, they will run on our servers and serve the ready made spectra (VOTable and other formats) for the researchers. Photometric redshift estimation (photoz) service: In the last couple of years with other researchers we have developed a method, which is capable to estimate redshift from photometry. In this way e.g. for the SDSS survey we could increase with two orders of magnitude the number of objects with known redshift. This method involves the connection of a spectrum template database (like the spectrum services above) and a photometry catalog (like the TB sized science archive of SDSS). We would like to run the estimation code on our servers, and provide the redshift estimation as a web service. Linking web services to GRID clusters: Both the Synthetic spectrum and the Photometric redshift estimation services require intensive computational power. Probably the spectrum and photoz servers alone will not be enough to execute the calculations in a reasonable time, so we have to connect them to compute clusters. Another difficulty is that different simulations are optimized for different operating system environments, and rewriting of the codes would be a prohibitive task. There is a convergence between the emerging new GRID standards and Web services, but a lot of practical questions should be solved, e.g. web services for batch process administration. More "Web services ready" astronomical databases: The nice idea of VO is working only if we fill it with data. This is true not only for the future surveys but the existing ones, too. In the recent months we have started to convert some of the existing databases, and include them in SkyQuery (http://www.skyquery.net/). The next, more general version of this service (Open SkyQuery) is under development. Electronic journals in the VO: Researchers at the Konkoly Observatory of the Hungarian Academy of Sciences are working on VO-enabling the Information Bulletin on Variable Stars, a small journal published on behalf of Commissions 27 and 42 of the International Astronomical Union. Main goals of the project: i.) serving tables published in the journal, and auxiliary files containing observational data in VOTable format; ii.) implementing complex services involving the electronic IBVS and other databases/services like Simbad and Aladin of CDS; iii.) developing web services enabling astronomers of locating and collecting variability information from different sources, like automatic variability surveys, databases and journals (the IBVS), iv.) participating in interoperability and metadata standardization in issues relevant to IBVS. (http://www.konkoly.hu/IBVS/IBVS.html) Solar observations in the VO: The Debrecen Heliophysical Observatory is the host of a unique resource in Solar physics. This large white-light solar database is containing daily full solar disc photographs and derived sunspot data. The database (Debrecen Photoheliographic Data, DPD, and its precursor, the Debrecen Photoheliographic Results, DPR) continue the Greenwich Photoheliographic Results project, which was discontinued in 1976. (http://fenyi.solarobs.unideb.hu/DPD/index.html)