AAVSO Photometric All-Sky Survey (APASS), underway since 2010,
covers the entire sky from 7.5 < V < 16.5 magnitude, and in the BVugrizY
bandpasses. A northern and a southern site are used, each with twin ASA
20cm astrographs and Apogee Aspen CG16m cameras, covering 2.9x2.9 square
degrees with 2.6arcsec pixels. Landolt and SDSS standards are used for
all-sky solutions, with typical 0.02mag calibration errors on the bright
end.
Data Release 10 is a complete reprocessing of all 500K images taken with
the system, including hundreds of nights not part of DR9. Sextractor is
used for star finding and centroiding; DAOPHOT is used for aperture
photometry; the astrometry.net plate-solving library is used for basic
astrometry, supplanted with more precise WCS that utilizes knowledge of the
optical train distortions. With these changes, DR10 includes many more
stars than prior releases.
More information is available at http://www.aavso.org/apass.
Pic du Midi de Bigorre in the French Pyrenees is the place where coronagraphic images were first realized, by Bernard Lyot in the 1930s. Since then, the solar instruments at Pic du Midi regularly provide images of the solar disc, solar prominences and solar corona.
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.
Predictions of stellar occultations by the main planetary satellites
Short Name:
voccdb.epn_core
Date:
26 Feb 2025 14:03:55
Publisher:
Paris Astronomical Data Centre
Description:
The VOccDB database provides prediction and parameters of stellar
occultations by the main planetary satellites. Observations of a
stellar occultations help to better determine the size and the shape
of the occulting body, as well as its astrometric position at the
milli-arcsecond level precision. Only the main moons of giant planets
Jupiter, Saturn, Uranus and Neptune are considered in the event
prediction database. Predictions are provided over period 2023-2032,
up to visual magnitude 12 for the biggest satellites, and magnitude 14
for other satellites. For each stellar occultation event prediction,
the database provides circumstances and observational data, date and
timing of the occultation, star position and magnitude, excepted
duration, etc.
United States Naval Observatory, Flagstaff Station
Short Name:
USNOFS
Date:
11 Apr 2007 08:52:38
Publisher:
US Naval Observatory
Description:
The USNO Flagstaff Station Image and Catalogue archive
provides access to digitized images of the major Schmidt photographic surveys of the sky (POSS-I, POSS-II, SERC-J, SERC-R, SERC-EJ, SERC-ER, AAO-R etc.) and to astrometric catalogues derived from these data, including USNO-A2, USNO-B1 and NOMAD. The site provides catalogue data, finding charts, image data and a merge of the three.
United States Naval Observatory, Flagstaff Station Naming Authority
Short Name:
USNOFS auth
Date:
11 Apr 2007 08:52:38
Publisher:
US Naval Observatory
Description:
The USNO Flagstaff Station Image and Catalogue archive
provides access to digitized images of the major Schmidt photographic surveys of the sky (POSS-I, POSS-II, SERC-J, SERC-R, SERC-EJ, SERC-ER, AAO-R etc.) and to astrometric catalogues derived from these data, including USNO-A2, USNO-B1 and NOMAD. The site provides catalogue data, finding charts, image data and a merge of the three.
