... 1.1.2 Spectral Filters . 1.1.3 Quantum Efficiency and Exposure Limits . ... 1.2 Which Instrument to Use: WFPC2, ACS, NICMOS, or STIS? 1.2.1 Comparison of WFPC2 and ACS . 1.2.2 Comparison of WFPC2 and NICMOS . 1.2.3 Comparison of WFPC2 and STIS . ... WFPC2 . ... 1.6 What's New in Version 6.0 for Cycle 11 . ... 2.9 Calibration Channel . ... 3.3.3 LRF Photometric Calibration . ... 4.8.1 Sources of Dark Current . ... 8.10 Calibration Plan Summary . 8.11 Cycle 4 Calibration Plan . ...

Next: AXAF Recipes Up: ROSAT HRI Recipes Previous: Quantum Efficiency Correction (a.k.a. For some observations, a significant amount of data may have been rejected during SASS processing because the background level was higher than the calculated threshold for rejection. ... REJECTED EVENTS . ... The recipe will allow the user to include rejected events in the generation of a new qpoe file and filter on the background level. ... This creates a qpoe file with standard + rejected events. ...

... The first step to improve the FORS calibration is therefore to obtain data to allow a computation of the illumination correction across the field. ... Another limitation on the calibration accuracy has been the brightness of the Landolt standards which have forced the use of extremely short exposures introducing small but non-negligible shutter-time errors and also resulting in a very small number of useful standards per frame. ...

Target: Horsehead Nebula or Barnard 33 Date: 2012-10-09 Time: 16:53 Telescope: CDK20S Camera: Apogee U16 Filters: UBVRI Exposure time: 100 seconds each filter Observer: Rhodes Hart Processing: John Kielkopf Colors at the center of the field are approximately correct for visual response. The images are not flat fielded, and the vignetting changes the color balance progressively away from the center.

Next: GRISMCAL Up: COLORTRANS Previous: Generation from Ground Calibration Contents . The transformations from the OM instrumental system to the standard Johnson's system were established based on in-flight observations. ... We have derived the flux conversion factors from OM observations of seven spectrophotometric standard stars (white dwarfs: Hz4, GD50, GD153, LBB227, BPM16274, Hz2 and G93-48). ...

... Up: Proposal Processing . ... An automated observing proposal processing system has been in use at KPNO during the past three years. ... Observer and proposal information fields in these files are well-marked with LaTeX tags, thus allowing automated extraction and importation to observatory databases. ... The Kitt Peak observing proposal handling system (Bell et al. 1996) is an automated system for distributing, receiving, and processing LaTeX observing forms and associated PostScript figures. ...

... Tonight's Sky . ... Observing . ... Sky this Month . ... Star Atlas . ... stars . ... Observing Podcasts . ... Astronomy for Kids . ... Observing springtime deep-sky objects with a large telescope . ... How do neutron stars generate steady magnetic fields? ... How can a neutron star exist if those neutrons are just going to pieces? Get instant access to subscriber content on Astronomy.com! ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ...

Next: Radio pulse characteristics Up: An overview Previous: The structure of neutron . Typically Gauss for normal pulsars . Consistent with flux conservation during stellar collapse . ... Gravity dominates stellar structure . B field dominates exterior . Stellar surface is so small that observed emission is dominated by the magnetic field. ... Only field lines inside light cylinder are closed . Particles are constrained move along field lines . ...

... NGC 188 is a moderately old open cluster in the disk of the Milky Way. The exposure was 631 seconds through B1, 315 seconds through A1 and 316 seconds through B5. 47-TUC is a metal-rich galactic globular cluster. ... M13 1490 seconds through A1 and B5. ... NGC 752 a galactic stellar cluster was observed for 1172 seconds through A1 and B5. The Hercules Cluster of Galaxies or Abell 2151 is a rather distant (by UIT imaging standards), spiral rich cluster with lots of interacting galaxies. ...

APO/GIFS Instrument Factsheet The Goddard imager and Integral Field Spectrograph (GIFS) has recently been commissioned on the APO 3.5 m telescope. This factsheet presents a high level overview of the GIFS instrument. ... GIFS Imaging The GIFS imaging mode is used for imaging science and target acquisition for the IFS mode. ... Imaging Mode pixel scale: 0.168"/pixel · Comparison to Other APO 3.5m instruments: The GIFS field of view is smaller than SPICAM, but the filter set is far more extensive. ...

... NICS will be the only infrared instrument for the first light of the TNG; as a consequence, we decided to incorporate a sufficient degree of operation flexibility by providing the instrument with six different observing modes, three aimed at imaging and three at spectroscopy: . ... It will be possible to use the narrow band filters as order sorters; this will allow to perform high resolution long-slit spectroscopy in the wavelength ranges covered by the available narrow band filters. ...

M obile A stronomical Sy stem of TE lescope- R obots MASTER-II Kislovodsk Lomonosov Moscow State University, Sternberg Astronomical Institute , Moscow Union "Optic" , Kislovodsk Solar Station Latitude = 43 o љ44'.767љN; Longitude = 42 o љ31'.417љE; Altitude = 2067љm MASTERљIIљ(8љsquareљdegress) + MASTERљVWF(VeryљWideљFieldљCameras (FOV=800 square degrees, Timeљresolutionљupљtoљ150љms, with unfiltered m_lim=14m on 5 sec. exposure, and ~10.5m with 0.15 sec) . ... 11h 38m 38.0s , -09d 59m 59s) . ...

... Exposure Time Calculator (ETC) . Survey processing . ... VISTA is a 4-m class wide field survey telescope for the southern hemisphere, equipped with a near infrared camera (1.65 degree diameter field of view at VISTA's nominal pixel size) containing 67 million pixels of mean size 0.34 arcsec and available broad band filters at Z,Y,J,H,K s and a narrow band filter at 1.18 micron. A wide field visible camera, if constructed, could also be used on VISTA. ... Tile . ... ESO VISTA Public Surveys . ...

The "ring of fire" seen by satellite cameras around the polar caps (picture below) is probably created by electrons leaking from the tail's plasma sheet, whose magnetic field lines form a somewhat imperfect trap. ... One possible explanation involves the close association between auroral arcs and electric currents which flow along field lines between the ionosphere and distant space ( Birkeland currents ). ... That produces an extra resistance to the flow of current. ...

... The Magnetic Sun . ... Galileo had guessed they were clouds floating in the Sun's atmosphere, obscuring some of its light. ... It turned out that the Sun has a polar field somewhat like the Earth's, but that it reverses its polarity during each 11-year cycle. ... Sunspot fields were evidently produced by electric currents, and it was well known that such currents could be generated by a " dynamo process ," by the motion of an electric conductor (e.g. the flow of solar plasma) through a magnetic...

NMW survey overview . Access image archive . ... The New Milky Way survey aims to detect bright (V<13.5) optical transients near the Galactic plane using an automated wide-field (8x6 deg.) system capable of surveying the whole Milky Way area visible from the observing site in one night. ... All images obtained during the transient search survey are available online (please use the image archive access form ). ... Images per field: . ... Images per night: . ... Milky Way imaging time: . ...

Astronomy Picture of the Day . ... In this false-color picture, light blue regions are extremely hot - over 1 million degrees, while dark blue regions are slightly cooler. ... On the left is a normal star field containing the constellation Orion. ... A Star Where Photons Orbit . ... A Wolf-Rayet Star Blows Bubbles . ... Wolf-Rayet stars can blow bubbles. ... Wolf-Rayet stars generate bubbles because they continually eject their outer atmosphere as a stellar wind. ... Dark Bok Globules in IC 2944 . ...

... This appendix tells you how you can use JavaScript to filter your incoming mail and news when you use Netscape Messenger. ... Write a JavaScript function to serve as a filter and put it in your filters file. ... This file contains the JavaScript functions that perform the mail filtering. ... The following is an example of a simple mail filter file. ... It also sends all messages from my_sister to the trash folder. // filters.js file. function MomFilter(message) { . ... message.folder = f.folder; . ...

The low pass digital filters (lpdf) were simulated in software. ... Generate an in band sine wave (amplitude=10) and process it through the lpdf for each decimation. Generate noise (with an rms of 10) and filter it with the 4 decimations. ... Page 1: filter for decimate=4,8,16,32, The dcGain is the integral over each filter divided by the decimation length. ... Page 2: pushing a sine wave through the filter. ... Bottom: (sine waves)/decimation after filtering. ... Page 3: filtering noise. ...

... The French-Russian Poncelet Laboratory organizes the conference on "Random Processes, Conformal Field Theory and Integrable Systems", September 19-23, 2011, to take place in the Independent University of Moscow. ... In the last decades, the understanding of these processes has greatly benefited from the use of conformal field theory (CFT) and integrable systems (IS) which have been widely studied in the community of theoretical and mathematical physicists. ...