... An OBJECT column gives the name of the object observed (usually a star name). ... In critical cases, it is common practice to measure sky on two or more positions around a target object, and these positions must be identified. ... A general treatment of this problem requires a column called OBJECT, bearing the usual name of the object (as in the star tables); a column labelled STARSKY, to distinguish between star+sky, star alone, or sky alone; and additional columns to identify the sky position. ...

... To be read in conjunction with Section 4.11 of the WFPC2 Instrument Handbook , -Version 4.0. ... 1 The second study found evidence that CTE loss for faint stars has increased with time (Whitmore, 1998). The primary observational consequence of CTE loss is that a point source at the top of the chip appears to be fainter than if observed at the bottom of the chip, due to the loss of electrons as the star is read out down the chip (see Figure 1 ). ... Last updated: 06/16/98 10:38:00 . ...

... The J, H and K bands are characterized by a bright background, such a background is mainly due to the emission of atmospheric lines and of thermal radiation. ... If the source cover a large fraction of the slit, spectra off-source must be observed to adequately sample the sky background. ... The on chip integration time (time spent in each position of the slit) must not exceed 40 seconds in J and H bands and 60 seconds in K band. ... We suggest a sequence of 10 for each elementary integration time. ...

... A2324 Date Received: 2007-Apr-03 14:17:15 Technical Page Proposal Type: General Category: Sub-Category: Observation Category: Total Time Requested: Minimum Useful Time: Prop osal Title: ABSTRACT: Urgent Astronomy Spectroscopy Solar System 12 Hours 1 hour Arecibo OH Observations of C/2007 E2 Lovejoy We propose to observe recently discovered C/2007 E2 Lovejoy in April 2007. ... The velocity depends on the heliocentric distance, overall gas production rate, and varys widely among different comets. ...

... Science Users Information > Observing with ESO Telescopes > Phase 2 Preparation > Observing conditions . ... Service Mode Philosophy . ... The following definitions of the observing conditions are common between Phase 1 preparation and Phase 2 preparation, as well as between Service Mode and Visitor Mode observations. ... There are additional Service Mode Policies and Service Mode Guidelines regarding the observing conditions. ... Seeing (Phase 1) and Image quality (Phase2) constraints . ... Moon . ...

Astronomy Terms - To Help You Study The Universe . Articles | ... Learning about the universe, or the study of astronomy, can be fun for the individual or for the whole family. ... Learning a few simple terms will help you with this fascinating study. ... You will use a telescope or binoculars for your observation of the sky at night. ... Celestial Terms . ... Meteor or a shooting star – the light caused when a meteoroid burns up in Earth's . ... www.astronomy.net . About Astronomy Net | ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Circular polarization of the bright side of Iapetus versus wavelength, obtained with FORS2 at the ESO VLT during the night 2011-03-28 at a phase angle of 0.77 . ... It can be noted that a change in signal occurs in circular polarization observations that are taken after rotating the instrument by 90 degree with respect to the intial position angle on the sky. ...