свальная астростатистика
В конце года часто подводят итоги. Давайте оставим лытдыбры в стороне и посмотрим на некоторые аспекты статистики наблюдательной астрономии.
Очередное обновление статистики центра малых планет пришлось на конец декабря. Постоянно увеличивающиеся числа впечатляют - практически 97.8 миллионов, но не объектов, а зарегистрированных наблюдений, в ( Read more... )
Очередное обновление статистики центра малых планет пришлось на конец декабря. Постоянно увеличивающиеся числа впечатляют - практически 97.8 миллионов, но не объектов, а зарегистрированных наблюдений, в ( Read more... )
North (l=10 to 65 deg) + South (l=-10 to -65 deg), b=+- 1: 31,184,509 in catalog, 49,258,859 in archive. GLIMPSEI is single epoch data.
GLIMPSEII V2.0 Data Release. (Version 2.1 November 18, 2009)
From all epochs: data taken in September 2005 (epoch1), April 2006 (epoch2) and reobservations of bad/missing frames. Also includes GLIMPSEI data at the boundaries of the GLIMPSEII survey and the Galactic Center data from the Guest Observer Program GALCEN-PI Susan Stolovy.
5 l 10, 350 l 355: -1 b 1
2 l 5, 355 l 358: -1.5 b 1.5
0 l 2, 358 l 360: -2 b 2.
l=11 to -11 deg: 19,067,533 cat, 24,377,005 arch.
GLIMPSE3D V1.0 Data Release. (v1.0 DR Version 1.4 October 27, 2011)
Southern Galactic Plane (l<-9), Northern Galactic Plane (l>9), Inner Galaxy (|l|<9). Up to |b| < 3deg, but up to |b| < 4.2 deg in the center of the Galaxy.
Galactic Legacy Infrared Mid-Plane Survey Extraordinaire. GLIMPSEI, GLIMPSEII and GLIMPSE3D Enhanced Data Products.
Table 4. Photometric Accuracy of GLIMPSE3D Sources. Band, μm: [3.6] [4.5] [5.8] [8.0].
Catalog Total number of entries 20,288,341 19,792,208 9,783,136 7,033,224.
Archive Total number of entries 31,099,459 26,720,472 10,546,743 7,776,984.
GLIMPSE360 (v1.1 November 9, 2012)
GLIMPSE Documents.
8,294,139 Catalog sources and 9,074,819 Archive sources Single frame photometry; Highly Reliable Catalog, More Complete Archive IRAC bands 3.6 um and 4.5 um bandmerged with 2MASS J, H, Ks. latitudes -2.2...+1.6.
The GLIMPSE360 Catalog consists of the highest reliability point sources.
The GLIMPSE360 Archive consists of point sources with less stringent selection critera than the Catalog. The number of Archive sources as a function of magnitude for each IRAC band is shown in Figures 3 & 4. The Catalog is a subset of the Archive, but the entries for a particular source might not be the same due to additional nulling of magnitudes in the Catalog because of the more stringent requirements.
Numerous complementary datasets will increase the scientific impact of the Spitzer Galactic Plane Surveys. We list several of these surveys: 1. 2MASS 2. TheMidcourse Space Experiment (MSX) 3. Herschel Infrared Galactic Plane Survey (HI-GAL and HI-GAL360) 4. Wide-field Infrared Survey Explorer (WISE) 5. AKARI infrared survey 6. UKIDSS-GPS (UKIRT Infrared Deep Sky Survey Galactic Plane Survey) 7. VVV (Vista Variables in the Via Lactea) is an ESO near infrared variability survey of the Milky Way bulge and an adjacent section of the mid-plane 8. UWISH2 (UKIRT Widefield Infrared Survey for H2 is imaging about 150 square degrees along the Galactic plane 9. Submillimetre Common-User Bolometer Array 2 (SCUBA-2) is an all-sky survey in the sub-millimeter (200 μm to 1 mm) 10. Galactic Australian SKA Pathfinder Survey (GASKAP) 11. Five-College Radio Astronomy Observatory (FCRAO) CO surveys of the Outer Galaxy 12. Milky Way Galactic Ring Survey (GRS) 13. Arecibo and Green Bank Telescope (GBT) surveys of IR-color selected H II Regions in the GLIMPSE survey region: a dataset that resolves distance ambiguities to massive star formation regions. 14. The International Galactic Plane Survey is an HI 21-cm survey of the disk of the Milky Way. 15. The Coordinated Radio and Infrared Survey for High-Mass Star Formation (CORNISH) Very Large Array (VLA) 6 cm continuum survey of much of the Galactic plane. 16. The Galaxy ALFA Low Latitude HI Survey (GALFA) 17. The Bolocam Galactic Plane Survey is a 1.1 mm continuum survey of 170 square deg of the Galactic plane visible from the northern hemisphere. 18. The APEX Telescope Large Area Survey of the Galaxy (ATLASGAL), It mapped over 400 square degrees at 870 microns in the inner Galaxy.
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UKIDSS is a set of five surveys.
Planned final UKIDSS 7-year sky coverage. The dashed line marks the Galactic plane, and the dotted line marks the ecliptic. Note that UKIRT lies at latitude +20 deg:
5-sigma depth in K:
1. Large Area Survey (LAS) 4000 sq. degs K=18.4 extraGal
2. Galactic Plane Survey (GPS) 1800 sq. degs K=19.0 Gal
3. Galactic Clusters Survey (GCS) 1400 sq. degs K=18.7 Gal
4. Deep Extragalactic Survey (DXS) 35 sq. degs K=21.0 extraGal
5. Ultra Deep Survey (UDS) 0.77 sq. degs K=23.0 extraGal
Releases:
January 14th 2013: UKIDSS DATA RELEASE 10 (DR10).
LAS 219,022,515 objects in detection table, 84,440,794 sources in source table.
April 25th 2012: World public release of UKIDSS DR8+ (excluding GPS) (Sept 3rd 2010, UDS added Oct 19th 2010, GPS added Feb 17th 2012).
LAS 175,202,369 objects in detection table, 69,656,410 sources in source table.
April 20th 2012: GPS included in UKIDSS DR7 for public access.
August 10th 2007: WORLD public release of the UKIDSS EDR.
February 10th 2006: EARLY DATA RELEASE: FIRST ESO-WIDE RELEASE OF UKIDSS SURVEY DATA.
Summary of the survey programme components. K-band limiting magnitude versus area for various near-IR surveys. In blue : the proposed UKIDSS survey components. In red : various other surveys, either completed or underway. The dashed line shows the Euclidian number counts relation.
There are 6 large public surveys being conducted by VISTA: UltraVISTA, VIKING: VISTA Kilo-Degree Infrared Galaxy Survey, VMC: VISTA Magellanic Survey, VVV: VISTA Variables in the Via Lactea, VHS: VISTA Hemisphere Survey, VIDEO: VISTA Deep Extragalactic Observations Survey. These will take up the majority of the observing time in the telescope’s first five years of operations. The surveys cover different areas of sky to different depths to attack a wide range of scientific questions.
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Hi-GAL Herschel Infrared Galactic Plane Survey - The largest Herschel open-time key project. Wavelength Coverage 70-500 μm, Sky coverage 2°x360°, |b| ≤ 1° (following the Galactic warp), PACS and SPIRE observe simultaneously, Scan speed 60”/sec.
Hi-GAL 1: |b| < 1, l -71 - 66 deg. Hi-GAL 360 & 2pi: the whole plane.
Band Nominal beam (“) Pixel size (“) Tot pixel
PACS 70 5.2 3.2 ~1700x1700 (~3000x3000 total?)
PACS 160 12.0 4.5 ~1200x1200
SPIRE 250 18.0 6.0 ~1000x1000
SPIRE 350 24.0 8.0 ~700x700
SPIRE 500 34.5 11.5 ~500x500
Preliminary catalogue in Hi-GAL “1”: ~ 400,000 sources.
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Two instruments: the Far-Infrared Surveyor (FIS; Kawada et al. 2007) for the far-infrared observations and the Infrared Camera (IRC; Onaka et al. 2007) for the near and mid-infrared wavelengths, 9-200um.
AKARI was launched on 2006 February 22. AKARI All-Sky Survey started in 2006 May and was completed in 2007 August.
The post-Helium phase (Phase 3) routine observations (only with IRC) have started on June 1st, 2008.
The operation of satellite was terminated officially on 24 November 2011.
The Akari All-Sky Survey Point Source Catalogues was released on 30 March 2010. This release consists of two infrared catalogs: the FIS Bright Source Catalogue (BSC; Yamamura et al. 2010) with 427,071 objects observed in the four far-infrared wavelengths, and the IRC Point Source Catalogue (PSC; Ishihara et al. 2010) including 870,973 objects in the two mid-infrared wavelengths. The catalog set covers more than 98% of the sky.
Note that image data of the AKARI All-Sky Survey are not yet publicly released (1107.5385).
A total of 877,091 sources (851,189 for 9um, 195,893 for 18um) are confirmed and included in the current release of the point source catalogue. The detection limit for point sources is 50mJy and 90mJy for the 9um and 18um bands, respectively. The position accuracy is estimated to be better than 2".
"Asteroid catalog using AKARI (AcuA)" is open to the public on 16 Sep. 2011.
IRAS PSC: 245,889 well-confirmed point sources, i.e., sources with angular extents less than approximately 0.5', 0.5', 1.0', and 2.0' in the in-scan direction at 12, 25, 60, and 100 µm, respectively. Typical position uncertainties are about 2" to 6" in-scan and about 8" to 16" cross-scan. Version and release date: 2.0, 1990 Sept
IRAS FSC: Faint Source Survey (FSS) is the definitive IRAS data set for faint point sources. The FSS was produced by point-source filtering the individual detector data streams and then coadding those data streams using a trimmed-average algorithm. Averaged over the whole catalog, the FSC is at least 98.5% reliable at 12 and 25 microns, and ~94% at 60 microns. For comparison, the IRAS Point Source Catalog (PSC) is > 99.997% reliable, but the sensitivity of the FSC exceeds that of the PSC by about a factor of 2.5. The FSC contains data for 173,044 point sources in unconfused regions with flux densities typically greater than 0.2 Jy at 12, 25, and 60 microns and greater than 1.0 Jy at 100 microns.
Sources with SNR > 3 but which do not meet the reliability requirements of the FSC are cataloged in the Faint Source Reject File (FSR). The FSR contains data for 593,516 sources.
Version and release date: 2.1, 1989 July 25
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SPIRIT III infrared off-axis telescope (33-cm eff aperture, "35 clear"), Bands A (8.28µm), B1&B2 (4.22-4.36, 4.24-4.45µm), C (12.13µm), D (14.65µm), E (21.3µm). Band A much more (~10x) sensitive than the other bands.
Comparable sensitivity to the IRAS but with a 40x smaller point response func
Area Coverage: l 0-360, |b| < 5, IRAS gaps, select targets. MSX point Source Catalog Version 2.3 V2.3 contains 440,487 sources in the main catalogues (V1.2 contained 323,052 - ~3x more than in IRAS cats within the same region). Of these, 431,711 are included in Galactic plain survey (|b|<6) and 8,776 are in the areas missed by IRAS at lats higher |b|=6 or in the LMC. Most (~73%) of the sources were only detected in band A. Total B1 1495, B2 3406, A 438817, C 56193, D 54687, E 23582.
Cat >90% complete in band A down to a flux limit of ~158 mJy (mag 6.4) and >50% above 125 mJy. Band C: >90% brighter than 0.7 Jy, >50% - >0.3 Jy. D: 0.5 Jy, 0.3 Jy, E: 1.5 Jy, 1 Jy. B1 20, 10 Jy, B2 10, 4 Jy.
Supplement for PSC V2.3 - sources extracted from only a single scan. Total 12,179 sources are included in singleton cat. Of these, 11,802 have band A.
Low reliability Source file - supplemental faint source reject file: 75,644 sources, 75,127 in A, C 4481, D 4090, E 4671. Some of these are extended objects.
Mini-catalog areas include M31 (99 sources), M33 (52), SMC (243), Orion (457)...
The cryogen phase of the mission ended on 26 February 1997.
The "post-cryogen" phase will focus on celestial and terrestrial backgrounds, surveillance demonstrations, and environmental research.
The 4-5 yr mission - cryogen phase, during which IR measurements are a priority and the post cryogen phase using the suite of UV through visible (red) sensors.
Showcase.
The Wide Field Infrared Explorer (WIRE) was a satellite launched on 5 Mar 1999. WIRE was intended to be a 4 month IR survey of the entire sky at 21-27 and 9-15 µm. The original science goals of WIRE may finally be achieved by the WISE.
WISE (40 cm) provides an all-sky survey from 3 to 25 microns which is up to 500x more sensitive than the IRAS survey.
July 31, 2012: NEOWISE Post-Cryo Preliminary Data Release consists of over 900,000 3.4 and 4.6 micron images and a database of over 4.9 billion source detections extracted from those images, acquired between Sept 29, 2010 and Feb 1, 2011 after the satellite's solid hydrogen cryogen was completely exhausted. During this 115 day period, known as the NEOWISE Post-Cryo survey phase, the telescope and payload warmed to approximately 73.5 K, and the 3.4 and 4.6 micron detectors continued to operate with nearly the same sensitivity as in the full cryogenic mission phase with only a small increase in the number of high noise pixels. WISE obtained multiple, independent observations of approximately 70% of the sky during the Post-Cryo phase, completing a survey of the inner Main Asteroid Belt and a second coverage epoch of the inertial sky.
Mar 14, 2012: All-Sky Data Release mapped the sky at 3.4, 4.6, 12, and 22 μm (W1, W2, W3, W4) in 2010 with an angular resolution of 6.1", 6.4", 6.5", & 12.0" in the four bands. WISE achieved 5σ point source sensitivities better than 0.08, 0.11, 1 and 6 mJy in unconfused regions on the ecliptic in the four bands. Sensitivity improves toward the ecliptic poles due to denser coverage and lower zodiacal background.
The All-Sky Release includes all data taken during the WISE full cryogenic mission phase, 7 Jan 2010 to 6 Aug 2010.
The WISE Source Catalog contains the attributes for 563,921,584 point-like and resolved objects detected on the Atlas Intensity images.
Reject Table - DB of 283,887,651 "sources", S/N<5.
Single-exp Source Database - DB of 9,479,433,101 "sources".
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И все-таки: почему SWAS работал с 1998 по 2004 (и еще немного в 2005-м) г.г., а Гершелю после окончания хладагента следует немедленно врезаться в Луну?.. Видимо, причина все же в принципиальном различии аппаратуры: the heat actually destroys the detectors, so the telescope would be useless after that.
Тем не менее, в недалеком (мы все надеемся) будущем будут запущены ИК и (суб)мм миссии с "пассивным" охлаждением, что существенно продлит срок их службы. Речь о телескопе им. Джеймса Вебба, который по стоимости рискует догнать Хаббл, и наш Миллиметрон, который, разумеется, на порядки дешевле.
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