Very Large Telescope and NACO Instrumentation

Very extensive squelch and NACO InstrumentationThis radical describes the Very monumental squash begin in Chile, the VLT consists of quadruple unit of measurement Telescopes with master(prenominal) r everberates of 8.2m diam and quartet moveable Auxiliary Telescopes with briny reflects of 1.8m diameter.One of the unit Telescopes, UT 4, is discussed in more than expatiate, specifically its location, mounting, optics, the range and focus locations and the available legal documents.The last part of the report is an example of an manifestation planning to image the Becklin-Neugebauer (BN) aspiproportionn with the NACO S13 camera and K band filter.IntroductionThe Very Large Telescope set off (VLT) is at this moment the worlds most advanced visual instrument (1), the VLT is located on the Paranal spotter, happen Figure 1, in the Atacama desert Northern Chile (70 24 11 West 243731 South).The Paranal mountain is probably the best website for astronomical observations i n the southern hemisphere, with e.g a humidity of 5-20% and a maximum rainfall of about 100 mm per year.The spotter is divided into 2 atomic number 18as, a telescope platform at the overstep of the mountain at an altitude of 2635 meters. and a base live at the foot at an altitude of 2360 m.The observations take place at the telescope platform, the base camp contains staff quarters, maintenance facilities, including a visitorscentre for the public.Overview of the VLTThe VLT consists of four identical Unit Telescopes (UT) with main reverberates of 8.2m diameter and four movable 1.8m diameter Auxiliary Telescopes, located on the telescope platform, watch over Figure 2 .The Unit Telescopes argon Ritchey-Chrtien telescopes, they bear operate in Cassegrain, Nasmyth or Coud focus. The four Unit Telescope let an altitude-azimuth (alt-az) mounting (2).The Unit Telescopes have fixed locations, the Auxiliary Telescopes potty be repositi atomic number 53d on 30 different stations, the UT and AT telescopes can be apply in several different musical personal mannersindependent telescope systemcombined perspicuous mode or VLT interferometer (VLTI)combined in seamless(prenominal) modeIn the independent telescope mode each UT is used separately, in the combined coherent mode the UT and AT telescopes subject handle together, in groups of dickens or three, to form a giant interferometer endowment an angular resolution equivalent to a telescope with a diameter of 200 meters and in the combined incoherent mode the four UTs are combined providing the total lightness collecting fountain of a 16-metre unmarried telescope.For the four Unit Telescopes, names of rejects in the sky in the Mapuche wording were chosen and they are now known as Antu (UT1, The Sun ), Kuyen (UT2, The moonshine ), Melipal (UT3, The Southern Cross ), and Yepun (UT4, Venus as evening star). Unit Telescope 4 (Yepun), see Figure 3 is discussed in more detail in the next sectionThe VLT instruments includes coarse-field imagers, adaptive optics corrected cameras and spectrographs, mellowed-resolution and multi- target area spectrographs run at wavelengths ranging from deep ultraviolet (0.3 nm) to mid-infrared (24 m).With these instruments important data can be collected for a large range of research topics such asformation and evolution of galaxiessearch for extra-solar piece of papertary formsdistances to galactic Cepheidscircumstellar phonograph records around unripe stellar endsactive galactic nucleistellar evolutionfundamental literary arguments of the beingUnit Telescope 4Optical set-upUnit Telescope 4 can operate in four foci two Nasmyth, virtuoso Cassegrain and one Coud focus (2), for the optic lay-out, including the eight mirrors (M1 to M8) and the main dimensions see Figure 4. descend is collected by the primary mirror M1 and concentrated by the supplementary mirror M2 either to the Cassegrain focus below the primary mirror or to one of the two Nasmyth foci, at the side of the telescope.In the Nasmyth configu ration the ocular layout is of the Ritchey-Chrtien type, the Cassegrain focus but is not of the Ritchey-Chrtien type, ever-changing amidst the two foci mean repositioning of the secondhand mirror and changing the curvature of the primary mirror.By transferring one Nasmyth focus to another location in the telescope basement the Coud focus is obtained (mirror M4 to M8), from the Coud focus the light can be sent to the conspiracy mode focus or to the interferometric focus.The Coud focus is located below the main telescope social organisation.The primary mirror (M1)The 8.2 m primary mirror of UT4 is make of Zerodur and is 175 mm thick the shape is actively controlled by centre of 150 axial forces actuators, the mirror has a central hole of about 1.0 m. .Zerodur is a glass-ceramic made by Schott Glaswerke AG (Mainz, Germany).The secondary mirror (M2)The secondary mirror is a convex hyperbolic mirror made of a tomic number 4 with an external diameter of 1.12 metres and a thickness of 50 mm.By changing the position and orientation of the mirror it is possible to correct some optical aberration of the telescope (defocus and decentring coma) and to change the signifying .The secondary mirror is supported by the M2 Unit at the top of the telescope and reflects the light from the M1 mirror towards the M3 plane mirrorThe optical quality depends on the mode of the mirror, if the mirror is in the active mode (active optics field in operation) , the Central brashness proportion is larger than or equal to 0.98, with an atmospheric coherence length of 250 mm at a wavelength 500 nm.In the passive mode, active optics correction not in operation, the root mean square (RMS) slope shift of the surface of the mirror is less than 0.7 arcsec.The tertiary mirror (M3)The tertiary mirror is flat and elliptically shaped (890x1260mm2), the mirror is made of Zerodur and produced by Schott Glaswerke AG.In Nasm yth configuration, see Figure 5, the M3 mirror deflects the light beams towards the scientific instruments located at one or the other Nasmyth focus.In Cassegrain configuration, Figure 5, the M3 mirror assembly is remotely flipped in towed position, parallel to the axis of M3 Tower.Mirror M4 to M8 ( the Coud train)The Coud give lessons is based on a combination of cylindrical and spherical mirrors, the lightis sent to the Coud Train by mirror 4 (M4) a concave cylindrical mirror in movement of the Nasmyth adapter.Relay optics provide an image of the sky at the Coud focus, the relay optics consists of the following mirrorsM5 a concave spherical mirror (R = 8975 mm)M6 a concave cylindrical mirror (R = 290,000 mm) , the cylinder direction is rotatedby 90 with respect to M4M7 a concave spherical mirror ( R = 5176.2mm)M8 a flat mirror.Technical descriptionThe telescope mounting of Unit Telescope 4 (3) is altitude-azimuth (alt-az), the telescope metro moves around a plane axis (the alt itude axis ), the two bearings which support the telescope vacuum tube are mounted on a fork rotating around a vertical axis (the azimuth axis)The telescope tube is a steel structure, supporting at the bottom the primary mirror (M1) , and at the top the M2 Unit, with the secondary mirror, by metallic beams (spiders).Unit Telescope 4 is protect by an enclosure, this enclosure also provides access for operation and maintenance to authentic areas of the telescope and a protection against the wind during observations. The telescope is mounted on a concrete foundation, the telescope pier. The geographical coordinates of UT4 are latitude 24 37 31.000 South and longitude 70 24 08.000 WestThe structure of Unit Telescope 4 consists of a large number subassemblies and parts see Figure 6 , some of the main assemblies arethe tube structure with the M2 spiders which hold the M2 unit .the fork structure with two Nasmyth platforms that support the Nasmyth instyruments.the Coud tube that provi des the interface to the Coud mirror units.azimuth tracks which support the fork structure.an azimuth platform which provides access for the Cassegrain instrument.SpecificationsAdaptive and active opticsUT4 has adaptive optics (AO) correction both at Nasmyth and at Cassegrain foci, UT4 is also equipped with a sodium laser conduct star facility for active optics.For the non-AO telescope operation the Central vehemence Ratio (CIR) quantifies the image quality. A broad(prenominal) CIR implies high signal throughput, high contrast and small image size.The peak signal in the long-exposure point sp discover function is given by (4) comparewhere is ta the transmissivity of the standard pressure, r0 the coherent wave-front size, tt the transmissivity of the telescope optics, D the diameter of the telescope and CIR the Central Intensity Ratio.The Central Intensity Ratio defined by comparabilitywhere y0 is the Strehl ratio of the telescope. (Strehl ratio is the ratio of peak diffraction intensities of an aberrated wavefront versus a perfect wavefront).The optical quality specification is that the Central Intensity Ratio CIR = 0.82 with a coherent wave-front of size r0 = 500 mm ( comprehend angle 0.2 arcsec) at = 500 nm. reach of viewThe total field of view (FOV) for UT4 in the Cassegrain focus is 15 arcmin, in the Nasmyth focus 30 arcmin and in the Coud focus 1 arcmin.atmospherical dispersionThe atmospheric dispersion is corrected up to zenith angles of 50 for instruments requiring high image and spectrophotometric quality.Pointing and trackingUT4 is able to get any target to in spite of appearance 70 zenith distance in less than 3 minutes. Offset pointing of 45 and 60 in altitude and azimuth respectively is possible in spite of appearance 35 seconds, to at heart 0.1 arcsec accuracy.UT4 tracks better than 0.05 arcsec RMS over a cessation of 15 seconds without victimisation guide-star position information, and over a one hour level when using guide-star tracki ng.Zenith distanceThe UT4 can operate at zenith distances ranging from 0.5 to 70, rampart by adjacent enclosures is limited to zenith angles larger than 60.InstrumentationThe instruments that are mounted on Unit Telescope 4 are shown in prorogue 1.HAWK-IHAWK-I is a near-infrared (0,85 2.5m) wide-field imager installed at the Nasmyth A focus of UT4 , the operating temperature of the instrument is 120 K, operating temperature of the sensors is of 80 K (3).HAWK-I has 10 observing filters primed(p) in two filter wheels Y, J, H, Ks , 6 narrow-band filters Brg, CH4, H2 and three cosmological filters at 1.061, 1.187, and 2.090 m.SINFONISINFONI is a near-infrared (1-2.5 m) integral field spectrograph installed at the Cassegrain focus of UT4.The spectrograph works with 4 gratings J, H, K, H+K with ghostly resolutions of R is 2000, 3000 and 4000, check to the J, H and K gratings respectively, and R is1500 with the H+K grating. The resolution power R of a spectrograph is given by Equati onwhere c is the velocity of light and dv the radial velocity .NACO (NAOS + CONICA)The Nasmyth Adaptive Optics System (NAOS) and the lofty Resolution Near IR Camera (CONICA) are installed at the Nasmyth B focus of UT4. NACO provides adaptive-optics corrected imagery, polarimetry, spectroscopy, and coronagraphy in the 1-5 m range.The NACO instrumentation will be discussed in more detail in the next section.Laser channel StarThe Laser Guide Star is an artificial source, a 4W CW atomic number 11 Laser (589 nm) will be used for this. The laser beam is focused at an altitude of 90 km, at that height an atomic sodium layer is present which backscatters the spot image, producing an artificial star with a order range from 11 mag. to 14 mag.NACO instrumentationInstrument characteristicsNAOSNAOS is an adaptive optics (AO) system that has been designed to work with natural guide stars (NGS) and moderately extended sources , NAOS can also use the laser guide star facility (LGSF) and a nat ural tip-tilt source (TTS) to provide adaptive optics correction (3).NAOS gives a upthrow corrected f/15 beam and a 2 arcmin field of view to CONICA. Two off-axis parabolas re-image the telescope pupil on the deformable mirror and the Nasmyth focal plane on the entrance focal plane of CONICA.A dichroic-filter splits the light between CONICA and the wave front sensor, a field getor is primed(p) after the wave front sensor input focus to select the reference bearing for wave front sensing, see Figure 7.NAOS has two wavefront sensors one visible light and one near-IR sensor , the two sensors are of the Shack-Hartmann type. It is possible to select an off-axis natural guide star within a 110 arcsec diameter field of view (FOV). NAOS allows wave front sensing with faint natural guide stars and extended objects, observations of very voguish objects are possible with the visible wave front sensor using neutral density filters.CONICACONICA is an infra-red (IR) (1 5 m) imager and spect rograph which is fed by NAOS.CONICA is subject of imaging, long slit spectroscopy, simultaneous differential imaging (SDI), coronagraphy, polarimetry , with a large range of plate scales, filters and masks.The CONICA sensor is a InSb Aladdin 3 array, the parameters of the array areformat 10261024 pixelspixel size 27mdark watercourse 0.05-0.15 ADUs-1 pixel-1wavelength range 0.8-5.5 mQuantum efficiency 80-90 %The detector has three readout modes and four detector modes .The readout modes refer to the way the array is read out, the read our modes are UncorrThe array is reset and then read once, used for situations when the primer coat is high.The negligible detector integration succession (DIT) is 0.1750 seconds.Double_RdRstRdThe array is read, reset and read again, used for situations when the setting is intermediate between high and low.The minimum DIT is 0.3454 seconds.FowlerNsampThe array is reset, read four clippings at the beginning of the integration ramp and four metres again at the end of the integration ramp. Each time a pixel is addressed, it is read four times. This is used for situations when the background is low.The minimum DIT is 1.7927 seconds.The detector mode refers to the setting of the array bias voltage, four modes have been defined HighSensitivity, HighDynamic, HighWellDepth and HighBackground.HighSensitivity has the fewest hot pixels, but it has the smallest well judgment, this mode is used for long integrations in low background situations.HighBackground has the largest well depth but has many more hot pixels, this mode is used in high background situations .S13 cameraCONICA is equipped with several cameras such as S13, S27, S54, the characteristics of camera S13 are scale 13.221 0.017 mas/pixel, field of view (FoV)1414 arcsec and spectral range 1.0-2.5 m.Available filters for the S13 camera are broad- and narrowband filters in the 1-2.5 m region, study on the broadband filters can be found in gameboard 1.Unit Telescope 4 param etersExample observation planningThe observation planning contains the next subjects (5)targetscientific goalvisibility stoppage of target infallible observing conditionsseeingatmospheric transparencylunar illuminationrequired observing timelist of required instruments, modes and configurations tailThe chosen observation target is the Becklin-Neugebauer (BN) object located in the huntsman Nebula Cluster, coordinates right ascension (RA) 05h 35 m 14s.117 and declination (D) -05 2222.90, epoch 2000.0,scientific goalThe Becklin-Neugebauer object was discovered as a bright 2 m infra-red source (10) by Becklin and Neugebauer in 1967 (11), about 45 in projection from the Trapezium stars of the Orion Nebula Cluster, at a distance of 450 pc.The Becklin-Neugebauer object together with the Kleinmann-Low nebula (KL) is part of the Orion Molecular Cloud 1 (OMC-1) region, a high-mass star formation region in the Orion constellation.In 2004 Shuping, Morris and bloody(prenominal) (8) discovered , at 12.5m, an arc of emission associated with the BN object, the so-called BN SW arc.The nature of this SW arc is still unknown, it may be externally heated petrol or dust by UV radiation or is mayhap a compressed shell created by an outflow or greens from BN.The BN SW arc is an interesting feature that needs further investigations both imaging and spectroscopy at other wavelengths to determine its true nature. inevitable observing conditionsSeeing/airmassSeeing is defined as the image intact width half maximum (FWHM )in arcsec ,the seeing values are 0.8and 1.2 at Zenith.Airmass quantifies the effects of all atmospheric processes, these atmospheric effects will be minimum when radiation travels vertically through the atmosphere, in this case z = 1.During the observation period the airmass ranges between z = 1.0 and z = 1.5 see table A, appendix 1, average airmass z = 1,2.Atmospheric transparencyDuring the observation period there should be no visible clouds and the transparency variations should be less than 2%.Lunar illuminationLunar illumination (FLI) is defined as the fraction of the lunar disk that is illuminated at local anaesthetic (Chile) obliging midnight, where 1.0 is fully illuminated.Dark time corresponds to moon illumination less than 0.4, so the best time to observe the target is when the moon is new, see arm 7.4.Visibility period of targetTo calculate the visibility of the target I have used the local sidereal time equationEquationwhere LST = local sidereal, HA = hour angle and RA = right ascension.RA of BN-object = 05h 35 m 14s.117 = 5.587 hr. , on 21 marching music RA = 12hr is on the meridian at local midnight.RA = 5.587 hr will be on the meridian at local midnight about (5.587-12.0)-30/2 = 96 days = 3 months earlier . Thus the target will be well placed in November 2011 and fallember 2011.New Moon is on 25 November 2011 and 24 December 2011, so the best dates to observe the BN- object will be 22-27 November and 22-26 December 2011, see table B, appendix 2.The chosen observation period is the night of 24/25 December 2011, between 22hr and 2hr local time.Required observing timeAngular resolutionThe supposed angular limit of resolution is given byEquationwhere l = wavelength, D = aperature diameterThe wavelength of the K-filter is l = 2.18 m, so the resolution isThe resolution however is limited by atmospheric turbulence towhere r0 is the Fried parameter.The Fried parameter is directly linked to the strength of the turbulence and it depends on the wavelength asEquationfor average observing conditions, r0 is about 0.6 m at 2.2 m.Seeing diskThe angular diameter of the seeing disk isEquationso for l = 2.18 m and r0 = 0.6 m field of view of seeing diskExposure timeExposure time Equationwhere t = integration timer = signal to noise ratiof = flux transmitted by atmospherefsky = sky background fluxa = area of seeing discA = effective area of telescope UT4Q = quantum efficiencyl = flux of the BN objectl = wavelength = 5.510-7 mh = Plancks constant = 6.6310-34 Jc = velocity of light = 3.0108 ms-1The adopted signal to noise ratio S/N = r = 5.The flux transmitted by the atmosphere f = 1.0, see figure 3.2 NACO User Manual (3)The liming sky background magnitude is 13.0 mag (3), the sky background fluxEquationArea of seeing disk a = 0.442 arcsecEffective area of UT4Quantum efficiency Q = 0.85The magnitude of the BN object corrected for extinction mv = 5.2 mag (11), the extinction in the V passband Av = 18 mag. (8) so the apparent magnitude of the BN object m = 23.2 mag.Flux /magnitude conversionEquationThe flux of the BN object isThe exposure time for the BN object ist = 639 sec.The exposure time measured with ETC is 122,320 seconds ? , see appendix 4 table D.List of required instruments, modes and configurationsThe required telescope to observe the BN object is UT4 with the NACOS instrumentation.The NAOS with natural guide star, the CONICA imager with camera S13 and broadband filter K (2.18 mm).The chosen detector readout mode is FowlerNsamp and not Double_RdRstRd because the intergration time is larger than 60 seconds.Guide star id. 0477400932, RA 05hr 35m 16s.41, Dec -05 23 23.0 magnitude 5.00 see table C, appendix 3,ConclusionThe Very Large Telescope array is at this moment the most advanced optical instrument and the most productive individual ground-based observatory in the world.The instrumentation programme is the most ambitious programme for a single observatory and because of to the outstanding angular resolution and the use of adaptive optics VLT opens a new era of discoveries.Bibliography/ReferencesESO http//www.eso.org/sci/facilities/paranalGiacconi R. The VLT White BookESOhttp//www.eso.org/public/products/books/vlt_whitebook/Girard J. et al. Very Large TelescopeNACO Users ManualDo. No. VLT-MAN-ESO-14200-2761Date 12-02-2010http//www.eso.org/sci/facilities/paranal/instruments/naco/doc/VLT-MAN-ESO-14200-2761_v86.0.pdfDierickx P., et al The VLT primary mirrors mirror production and measured performancehttp//www.eso.org/sci/facilities/paranal/telescopes/ut/m1unit.htmlde Zeeuw T. Call for ProposalsESO Period 8730 August 2010http//www.eso.org/sci/observing/proposals/CfP87.pdfMoorwood A. Astronomical NewsReport on the ConferenceScience with the VLT in the ELT EraHeld in Garching, Germany8-12 October 2007Minchin N.R. et al Near-infrared imaging polarimetry of bipolarNebulae-I. The BN-KL region of OMC-1Mon. Not. R. astr. Soc.(1991) 248,715-729Shuping R. Y., Morris M. and Bally J. A new mid-infra red comprise of the BN/KLRegion using the Keck telscopeThe Astronomical Journal, 128363-374, 2004 JulySansom A. UVOIR Astronomy AA2053University of Central Lancashire , 2010Tan J. The Becklin-Neugebauer disapprove as runaway B starejected 4000 years ago from the q1C system.The astrophysical Journal Letters11-12-2001http//arxiv.org/abs/astro-ph/0401552v2Robberto M. et al The Orion Nebula in the mid-infraredThe Astronomical Journal, 129000-0002005 MarchBecklin E.E., Neugebauer G. Observations of an infrared star in the OrionNebulaCalifornia Institute of technologyPasadena, CaliforniaSeptember 12,1966http//adsabs.harvard.edu/abs/1967ApJ147..799BTestor G. et al VLT/NACO near-infrared imaging andspectroscopy of N159-5 in the LMC HII difficult N159Astronomy Astrophysics469, 459-469 (2007)AppendicesAppendix 1Hourly airmasses for 05 35 14.12 -05 22 22.90Paranal Observatory (VLT)Sat, December 24, 2011*** Hourly airmass for Target ***Epoch 2000.00 RA 5 35 14.1, dec -5 22 23Epoch 2011.98 RA 5 35 49.5, dec -5 21 57At midnight UT date 2011 Dec 25, Moon 0.00 illum, 151 degr from objLocal UT LMST HA secz par.angl. SunAlt MoonAlt HelCorr22 00 1 00 2 31 -3 05 1.502 -118.5 -4.2722 30 1 30 3 01 -2 35 1.341 -121.5 -4.3223 00 2 00 3 31 -2 04 1.229 -126.1 -4.3823 30 2 30 4 01 -1 34 1.152 -132.8 -4.430 00 3 00 4 32 -1 04 1.101 -142.9 -4.500 30 3 30 5 02 -0 34 1.071 -157.8 -4.561 00 4 00 5 32 -0 04 1.059 -177.2 -4.621 30 4 30 6 02 0 26 1.066 162.7 -4.692 00 5 00 6 32 0 56 1.090 146.5 -4.75Table A Hourly airmasss during observation period.SkyCalc provided by courtesy of John Thorstensen, Dartmouth College. emailprotectedhttp//www.eso.org/sci/observing/tools/calendar/observability.htmlAppendix 2Observability for 05 35 14.117 -05 22 22.90Paranal Observatory (VLT)RA dec 5 35 14.1, -5 22 23, epoch 2000.0Site longlat +4 41 36.8 (h.m.s) West, -24 37 30 North.Shown local eve. date, moon phase, hr ang and sec.z at (1) eve. tumble,(2) natural center of night, and (3) morning twilight then comes number ofnighttime hours during which object is at sec.z less than 3, 2, and 1.5. nighttime (and twilight) is defined by sun altitude Date (eve) moon eve cent morn night emailprotectedHA sec.z HA sec.z HA sec.z 2011 Oct 11 F -8 54 down -4 28 2.5 -0 02 1.1 4.7 3.9 3.02011 Oct 26 N -7 45 down -3 31 1.7 +0 42 1.1 5.4 4.6 3.82011 Nov 10 F -6 33 down -2 32 1.3 +1 29 1.1 6.2 5.4 4.52011 Nov 24 N -5 25 5.7 -1 34 1.2 +2 17 1.3 7.0 6.2 5.3201 1 Dec 9 F -4 13 2.2 -0 29 1.1 +3 15 1.6 7.4 7.2 6.12011 Dec 24 N -3 05 1.5 +0 37 1.1 +4 19 2.4 7.4 7.0 6.12012 Jan 8 F -2 02 1.2 +1 44 1.2 +5 30 6.3 6.8 6.0 5.1Table B Observability of Becklin-Neugebauer objectSkyCalc provided by courtesy of John Thorstensen, Dartmouth College. emailprotectedhttp//www.eso.org/sci/observing/tools/calendar/observability.htmlAppendix 3ESO GSC Online Server motion ResultCenterRA 053514.117DEC -052222.90 lookup radius20 arcminutesnr gsc_id ra (2000) dec mag mu d pa1 0477400932 05 35 16.41 -05 23 23.0 5.00 F 1.15 1502 0477400931 05 35 16.47 -05 23 22.8 5.09 F 1.16 1503 0477400933 05 35 22.83 -05 24 57.8 5.09 F 3.37 1404 0477400871 05 35 17.10 -05 23 40.6 5.51 F 1.49 1505 0477400934 05 35 26.27 -05 24 58.2 6.40 F 3.98 1316 0477400930 05 35 17.16 -05 23 12.7 6.69 F 1.12 1387 0477801369 05 35 54.09 -05 37 43.2 7.09 T 18.28 1478 0477400906 05 35 31.37 -05 16 02.7 7.19 T 7.65 349 0477400906 05 35 31.26 -05 16 02.0 7.58 T 7.65 3410 0477801369 05 35 53.99 -05 37 42.1 7.74 T 18.25 14711 0477400935 05 35 31.33 -05 25 14.1 8.18 F 5.15 12412 0477400915 05 35 06.10 -05 12 15.5 8.28 F 10.32 34913 0477400809 05 34 46.89 -05 34 14.3 8.30 F 13.66 21014 0477400849 05 35 09.73 -05 27 52.6 8.53 F 5.60 19115 0477400823 05 34 55.20 -05 30 21.7 9.04 F 9.27 21116 0477400867 05 35 58.44 -05 22 31.0 9.11 F 11.03 9117 0477400855 05 36 27.09 -05 24 31.0 9.28 F 18.29 9718 0477400792 05 34 42.19 -05 07 14.2 9.39 T 17.10 33219 0477400894 05 35 34.18 -05 06 20.9 9.45 F 16.79 1720 0477400830 05 35 18.12 -05 03 54.5 9.48 F 18.50 321 0477400792 05 34 42.19 -05 07 14.3 9.55 T 17.10 33222 0477400890 05 35 31.28 -05 33 08.5 9.74 F 11.58 15823 0477400829 05 35 35.71 -05 12 20.5 9.78 F 11.39 2824 0477400877 05 35 21.17 -05 09 15.7 9.79 F 13.24 825 0477400812 05 35 00.05 -05 25 15.7 9.85 F 4.53 23126 0477400878 05 34 52.14 -05 33 08.1 9.96 F 12.06 20727 0477400810 05 34 49.89 -05 18 44.4 9.96 F 7.04 301gsc 1.0 25/Sep/1995.ESO/ST-ECF Archive ESO ST-ECF sponsor SearchSe nd comments to HYPERLINK http//archive.eso.org/comments/emailprotected/Page/cgi-bin/gsc.Table C Guide stars Becklin-Neugebauer object