Decametric radio observation from Nancay decameter array. The Nancay Decameter Array (NDA) at the Station de Radioastronomie de Nancay (SRN) is a phased array of 144 "Teepee" helicoidal antenna, half of which being Right Handed (RH) polarized and the other half being Left Handed (LH) polarized. Four receivers are currently connected to the NDA, sampling data in spectral ranges within 5 to 80 MHz.
United States Naval Observatory, Flagstaff Station
Description:
The U.S. Naval Observatory (USNO) announces the release of the first version of the Naval Observatory Merged Astrometric Dataset (NOMAD). The 100 GB dataset contains astrometric and photometric data for over 1 billion stars derived from the Hipparcos, Tycho-2, UCAC2, and USNO-B catalogs for astrometry and optical photometry, supplemented by 2MASS near-infrared photometry. For each unique star the "best" astrometric and photometric data are chosen from the source catalogs and merged into a single dataset. A sequence of priorities is followed and NOMAD contains flags to identify the source catalogs and gives cross-reference identifications. This first release of NOMAD is not a compiled catalog; that is, if a star is identified in more than 1 of the above mentioned catalogs, only 1 catalog entry is chosen. Thus the local and global systematic errors of the various source catalogs will be present in this version of NOMAD. All source catalogs astrometric data are on the International Celestial Reference System within the limitations of the source catalogs. For more information and data retrieval see our homepage www.nofs.navy.mil/nomad.
Outlier Analysis in Low-Resolution Spectra: DFBS and Beyond
Date:
11 Apr 2023 13:12:10
Publisher:
The GAVO DC team
Description:
Low-resolution spectra like those resulting from objective prism
observations or the RP/BP instrument on board of the Gaia astrometry
satellite enable a wealth of interesting science. This use case
investigates one use leading up to combining many VO resources: The
identification of misclassified objects from reference databases.
This tutorial introduces a few techniques for working with image
services in the Virtual Observatory (VO) in general, using services
containing plate scans as examples. It will discuss both exploratory,
interactive use, and scripting using pyVO.