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Gaia catalogues

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The Gaia catalogues are star catalogues created using the results obtained by Gaia space telescope.

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42-457: The catalogues are released in stages that will contain increasing amounts of information; the early releases also miss some stars, especially fainter stars located in dense star fields. Data from every data release can be accessed at the Gaia archive. The Initial Gaia Source List (IGSL) is a star catalogue of 1.2 billion objects created in support of the Gaia mission. The mission should have delivered

84-476: A 1969 album by Marvin Gaye Manual pulse generator , a device normally associated with numerically controlled machinery Mark-Paul Gosselaar , American actor Matías Pérez García (born 1984), Argentine footballer Max-Planck-Gesellschaft (Max Planck Society), a German non-profit research organization Media Planning Group, former name of Havas Media , a media division of Havas Miles per gallon,

126-477: A catalogue based entirely on its own data. For the first catalogue, Gaia DR1, a way was needed to be able to assign the observations to an object and to compare them with the objects from other star catalogues. For this purpose, a separate catalog of objects from several other catalogues was compiled, which roughly represents the state of knowledge of astronomy at the beginning of the Gaia mission. The Attitude Star Catalog

168-469: A field of one square degree each at the north and south poles. The north pole is relatively sparse and contains 164,468 objects, while the south pole is still in the region of the Large Magellanic Cloud and contains 448,478 objects. The GEPC data was needed right at the beginning of the mission for the initial calibration. The commissioning phase of the Gaia space probe ended on July 18, 2014. This

210-424: A measurement of fuel economy in automobiles , boats and other motorized vehicles Milford Proving Ground, one of several General Motors Proving Grounds Minutes per game in basketball Monopotassium glutamate , a flavor enhancer Motor Press Guild , a non-profit association for professionals within the motoring press Multiplayer game Multiplayer video game Multi-touch, physics and gestures ,

252-570: A million stars from that region. The full data release for the five-year nominal mission, DR4, will include full astrometric, photometric and radial-velocity catalogues, variable-star and non-single-star solutions, source classifications plus multiple astrophysical parameters for stars, unresolved binaries, galaxies and quasars, an exo-planet list and epoch and transit data for all sources. Most measurements in DR4 are expected to be 1.7 times more precise than DR2; proper motions will be 4.5 times more precise. DR4

294-557: A particular date and time . The International Celestial Reference Frame ( ICRF ) is a realization of the International Celestial Reference System using reference celestial sources observed at radio wavelengths. In the context of the ICRS, a reference frame (RF) is the physical realization of a reference system, i.e., the reference frame is the set of numerical coordinates of the reference sources, derived using

336-525: A prototype version of the forthcoming ICRF3 using 2820 objects common to Gaia -CRF2 and to the ICRF3 prototype. The third Gaia celestial reference frame ( Gaia –CRF3) is based on 33 months of observations of 1,614,173 extragalactic sources. As with the earlier Hipparcos and Gaia reference frames, the axes of Gaia -CRF3 were aligned to 3142 optical counterparts of ICRF-3 in the S/X frequency bands. In August 2021

378-529: A reference axis stability of approximately 20 μas; this was an order-of-magnitude improvement over the previous reference frame derived from (FK5). The ICRF1 contains 212 defining sources and also contains positions of 396 additional non-defining sources for reference. The positions of these sources have been adjusted in later extensions to the catalogue. ICRF1 agrees with the orientation of the Fifth Fundamental Catalog (FK5) " J2000.0 " frame to within

420-399: A set of distant extragalactic objects". This fixed reference system differs from previous reference systems, which had been based on Catalogues of Fundamental Stars that had published the positions of stars based on direct "observations of [their] equatorial coordinates , right ascension and declination" and had adopted as "privileged axes ... the mean equator and the dynamical equinox" at

462-481: A single photometric band for 1.1 billion stars using only Gaia data, positions, parallaxes and proper motions for more than 2 million stars" based on a combination of Gaia and Tycho-2 data for those objects in both catalogues, "light curves and characteristics for about 3000 variable stars, and positions and magnitudes for more than 2000 extragalactic sources used to define the celestial reference frame". The second data release (DR2), which occurred on 25 April 2018,

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504-722: A type of computer touch screen Music Producers Guild , an association of music producers in the United Kingdom MPG: Motion Picture Genocide , 1997 film Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title MPG . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=MPG&oldid=1238617925 " Category : Disambiguation pages Hidden categories: Articles containing German-language text Short description

546-726: A variety of linking techniques, the coordinate axes defined by the Hipparcos catalogue were aligned with the extragalactic radio frame. In August 1997, the International Astronomical Union recognized in Resolution B2 of its XXIIIrd General Assembly "That the Hipparcos Catalogue was finalized in 1996 and that its coordinate frame is aligned to that of the frame of the extragalactic sources [ICRF1] with one sigma uncertainties of ±0.6 milliarcseconds (mas)" and resolved "that

588-559: Is a subset of the IGSL, required for the first approximation in the iterative evaluation of the Gaia data. A first version was created in 2013, a more refined version in April 2014. In total, the Attitude Star Catalog contains 8,173,331 entries with information on position, proper motion and magnitude. Starting with Gaia DR2, the Attitude Star Catalog was replaced with a new list generated from

630-594: Is based on 22 months of observations made between 25 July 2014 and 23 May 2016. It includes positions, parallaxes and proper motions for about 1.3 billion stars and positions of an additional 300 million stars in the magnitude range g = 3–20, red and blue photometric data for about 1.1 billion stars and single colour photometry for an additional 400 million stars, and median radial velocities for about 7 million stars between magnitude 4 and 13. It also contains data for over 14,000 selected Solar System objects. The coordinates in DR2 use

672-561: Is based on hundreds of extra-galactic radio sources , mostly quasars , distributed around the entire sky. Because they are so distant, they are apparently stationary to our current technology, yet their positions can be measured very accurately by Very Long Baseline Interferometry (VLBI). The positions of most are known to 1 milliarcsecond (mas) or better. In August 1997, the International Astronomical Union resolved in Resolution B2 of its XXIIIrd General Assembly "that

714-501: Is different from Wikidata All article disambiguation pages All disambiguation pages International Celestial Reference System The International Celestial Reference System ( ICRS ) is the current standard celestial reference system adopted by the International Astronomical Union (IAU). Its origin is at the barycenter of the Solar System , with axes that are intended to "show no global rotation with respect to

756-555: Is expected to be released no earlier than mid-2026. The last catalogue, DR5, will consist of all data collected during the lifespan of the mission. It will be 1.4 times more precise than DR4, while proper motions will be 2.8 times more precise than DR4. It will be published no earlier than the end of 2030. The Gaia Archive is a catalogue that contains positions and brightnesses for 1.7 billion stars , including distances and proper motions for more than 1.3 billion stars. An outreach application, Gaia Sky , has been developed to explore

798-421: Is useful to distinguish reference systems and reference frames. A reference frame has been defined as "a catalogue of the adopted coordinates of a set of reference objects that serves to define, or realize, a particular coordinate frame". A reference system is a broader concept, encompassing "the totality of procedures, models and constants that are required for the use of one or more reference frames". The ICRF

840-603: The International Celestial Reference Frame (ICRF3) . Included is the Gaia Catalogue of Nearby Stars (GCNS), containing 331,312 stars within (nominally) 100 parsecs (330 light-years). The full DR3, published on 13 June 2022, includes the EDR3 data plus Solar System data; variability information; results for non-single stars, for quasars, and for extended objects; astrophysical parameters; and a special data set,

882-576: The (lower) precision of the latter. An updated reference frame ICRF2 was created in 2009. The update was a joint collaboration of the International Astronomical Union , the International Earth Rotation and Reference Systems Service , and the International VLBI Service for Geodesy and Astrometry . ICRF2 is defined by the position of 295 compact radio sources (97 of which also define ICRF1). Alignment of ICRF2 with ICRF1-Ext2,

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924-669: The Gaia Andromeda Photometric Survey (GAPS), providing a photometric time series for about 1 million sources located in a 5.5-degree radius field centered on the Andromeda galaxy. The release dates of EDR3 and DR3 were delayed by the effects of the COVID-19 pandemic on the Gaia Data Processing and Analysis Consortium. Gaia Focused Product Release from October 2023 focused on Omega Centauri and contained more that half

966-571: The Gaia Main Data Base (MDB), using the same criteria. IGSL contains a list of about 200 stars of different spectral classes and magnitudes needed for calibration of the photometric measurements. It is the result of the Gaia Spectrophotometric Standard Stars Survey (SPSS), a selection of stars using Earth-based data in advance of the Gaia mission. Previous catalogues for calibrating magnitudes could not be used for

1008-529: The Hipparcos Catalogue shall be the primary realization of the ICRS at optical wavelengths." The second Gaia celestial reference frame ( Gaia –CRF2), based on 22 months of observations of over half a million extragalactic sources by the Gaia spacecraft , appeared in 2018 and has been described as "the first full-fledged optical realisation of the ICRS, that is to say, an optical reference frame built only on extragalactic sources." The axes of Gaia -CRF2 were aligned to

1050-572: The Hipparcos Catalogue shall be the primary realization of the ICRS at optical wavelengths." The Hipparcos Celestial Reference Frame (HCRF) is based on a subset of about 100,000 stars in the Hipparcos Catalogue . In August 2021 the International Astronomical Union decided in Resolution B3 of its XXXIst General Assembly "that as from 1 January 2022, the fundamental realization of the International Celestial Reference System (ICRS) shall comprise

1092-481: The ICRF. Although general relativity implies that there are no true inertial frames around gravitating bodies, these reference frames are important because they do not exhibit any measurable angular rotation since the extragalactic sources used to define the ICRF and the Gaia -CRF are so far away. The ICRF and the Gaia -CRF are now the standard reference frames used to define the positions of astronomical objects . It

1134-667: The Third Realization of the International Celestial Reference Frame (ICRF3) for the radio domain and the Gaia-CRF3 for the optical domain." The ICRF, now called ICRF1, was adopted by the International Astronomical Union (IAU) as of 1 January 1998. ICRF1 was oriented to the axes of the ICRS, which reflected the prior astronomical reference frame The Fifth Fundamental Catalog (FK5) . It had an angular noise floor of approximately 250 microarcseconds (μas) and

1176-757: The calibration. These are well-observed objects selected according to Stetson Secondary Standards, but only Gaia data were used. A list of quasars based on the Large Quasar Astrometric Catalog was prepared for IGSL. This in turn goes back to the Sloan Digital Sky Survey. From the more than one million objects, a selection of 150,000 quasars was made, which are in the region of Gaia's magnitude limit. The selected objects are already well observed and documented. In most cases, quasars are very far away, so that their proper motions and parallaxes are negligibly small. Gaia Ecliptic Pole Catalogue (GEPC)

1218-502: The data processing procedure links individual Gaia observations with particular sources on the sky, in some cases the association of observations with sources will be different in the second data release. Consequently, DR2 uses different source identification numbers than DR1. A number of issues have been identified with the DR2 data, including small systematic errors in astrometry and significant contamination of radial velocity values in crowded star fields, which may affect some one percent of

1260-605: The effect of the galactocentric acceleration of the solar system, a new feature over and above ICRF2. ICRF3 also includes measurements at three frequency bands, providing three independent, and slightly different, realizations of the ICRS: dual frequency measurements at 8.4 GHz ( X band ) and 2.3 GHz ( S band ) for 4536 sources; measurements of 824 sources at 24 GHz ( K band ), and dual frequency measurements at 32 GHz ( Ka band ) and 8.4 GHz ( X band) for 678 sources. Of these, 303 sources, uniformly distributed on

1302-462: The galaxy in three dimensions using Gaia data. MPG [REDACTED] Look up MPG  or mpg in Wiktionary, the free dictionary. MPG or mpg may refer to: .mpg , one of a number of file extensions for MPEG-1 or MPEG-2 audio and video compression MPG (gene) , a human gene coding for N-methylpurine DNA glycosylase M.P.G. ,

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1344-406: The mission because many of these objects are too bright for Gaia to detect. It was anticipated that some of the stars selected may be previously unrecognized doubles or variable stars that would need to be deleted from the catalogue; for this reason the list contains more stars than necessary. For Gaia EDR3 (Early Data Release 3), a selection was made from more than 100,000 objects that were used for

1386-459: The procedures spelled out by the ICRS. More specifically, the ICRF is an inertial barycentric reference frame whose axes are defined by the measured positions of extragalactic sources (mainly quasars ) observed using very-long-baseline interferometry while the Gaia -CRF is an inertial barycentric reference frame defined by optically measured positions of extragalactic sources by the Gaia satellite and whose axes are rotated to conform to

1428-547: The radial velocity values. Ongoing work should resolve these issues in future releases. A guide for researchers using Gaia DR2, which collected "all information, tips and tricks, pitfalls, caveats and recommendations relevant to" DR2, was prepared by the Gaia Helpdesk in December 2019. Due to uncertainties in the data pipeline, the third data release, based on 34 months of observations, has been split into two parts so that data that

1470-523: The reference frame come from approximately 30 years of VLBI observations, from 1979 to 2009. Radio observations in both the S-band (2.3 GHz) and X-band (8.4 GHz) were recorded simultaneously to allow correction for ionospheric effects. The observations resulted in about 6.5 million group-delay measurements among pairs of telescopes. The group delays were processed with software that takes into account atmospheric and geophysical processes. The positions of

1512-628: The reference sources were treated as unknowns to be solved for by minimizing the mean squared error across group-delay measurements. The solution was constrained to be consistent with the International Terrestrial Reference Frame (ITRF2008) and earth orientation parameters (EOP) systems. ICRF3 is the third major revision of the ICRF, and was adopted by the IAU in August 2018 and became effective 1 January 2019. The modeling incorporates

1554-562: The second Gaia celestial reference frame ( Gaia –CRF2 ), which is based on observations of 492,006 sources believed to be quasars and has been described as "the first full-fledged optical realisation of the ICRS ... built only on extragalactic sources." Comparison of the positions of 2,843 sources common to Gaia –CRF2 and a preliminary version of the ICRF3 shows a global agreement of 20 to 30 μas, although individual sources may differ by several mas. Since

1596-535: The second extension of ICRF1, was made with 138 sources common to both reference frames. Including non-defining sources, it comprises 3414 sources measured using very-long-baseline interferometry . The ICRF2 has a noise floor of approximately 40 μas and an axis stability of approximately 10 μas. Maintenance of the ICRF2 will be accomplished by a set of 295 sources that have especially good positional stability and unambiguous spatial structure. The data used to derive

1638-434: The sky, are identified as "defining sources" which fix the axes of the frame. ICRF3 also increases the number of defining sources in the southern sky. In 1991 the International Astronomical Union recommended "that observing programmes be undertaken or continued in order to ... determine the relationship between catalogues of extragalactic source positions and ... the [stars of the] FK5 and Hipparcos catalogues ." Using

1680-688: Was created for measuring the poles. The southern part of the catalogue was compiled from observations made with the MPG/ESO telescope at the Max Planck Institute for Astronomy in La Silla, Chile. It contains precise positions, UBV I photometry for the southern field and the corresponding magnitudes. The northern part was created with the Canada–France–Hawaii Telescope on Mauna Kea, Hawaii. The GEPC v3.0 catalogue contains 612,946 objects from

1722-593: Was followed by a calibration phase of 28 days, during which the ecliptic poles were measured intensively. During this time, Gaia was operated in Ecliptic Poles Scan Law mode (EPSL), in which the two poles were measured twice during each revolution. The initial catalogue was used for Gaia DR1 to match Gaia -found objects to previous star catalogues. Gaia DR1, the first data release based on 14 months of observations made through September 2015, took place on 13 September 2016. It includes "positions and magnitudes in

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1764-403: Was ready first, was released first. The first part, EDR3 (Early Data Release 3), consisting of improved positions, parallaxes and proper motions, was released on 3 December 2020. The coordinates in EDR3 use a new version of the Gaia celestial reference frame ( Gaia –CRF3), based on observations of 1,614,173 extragalactic sources, 2,269 of which were common to radio sources in the third revision of

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