Once students get the hang of it, they can find and measure the brightness of Delta Cephei in a few minutes. ... of Delta Cephei . ... Oct. ... The following table lists the measurements of Delta Cephei made by one amateur astronomer in autumn 1990. ... 4.0 . ... This activity is a simplified version of one that appeared in Hands-On Astrophysics, a series of activities prepared by the American Association of Variable Star Observers with support from the National Science Foundation. << previous page | ...

... About ATNF overview . ... Australia Telescope Steering Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . ... Australia Telescope 20GHz Survey . ... Bright prospects: Comparing the H Survey with large-scale radio continuum emission . ... Prospects for comparisons between the AAO/UKST H \ survey and large-scale radio continuum emission are considered, with particular reference to the recently completed Parkes 2.4-GHz survey of the southern Galactic Plane. ...

... The concerns here are similar to those for observing bright targets; saturation and blooming of the bright companion PSF must not impact the faint target. Also, one may need to consider subtracting the PSF of the bright object, and effects which limit the accuracy of that subtraction. If the bright companion will saturate and bloom, it will be necessary to rotate the CCD so that blooming along the CCD columns does not obliterate the faint target. ...

... A detailed study of two consecutive bright points observed simultaneously with CDS, EIT and MDI is presented. The analysis of the evolution of the photospheric magnetic features and their coronal counterpart shows that there is a linear dependence between the EIT Fe XII 195? flux and the total magnetic flux of the photospheric bipolarity. ... In a follow-up study, we used wide slit (90arcsec240arcsec) movies of four EIT coronal bright points (BPs) obtained with CDS. ...

... 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. ...

... 205Anglada+ 0) and NH3(1,1) observations towards 172 different star forming regions (99 observed in both molecules) associated with H2O maser emission. We make a comparative study between the physical parameters obtained from the CS and NH3 spectra, and their relationship with the H2O maser emission. ... We find that both the CS and the NH3 lines are significantly wider in regions with H2O masers than in other regions. ...

... The bright supernova (hereafter SN) in the galaxy NGC 4527 was first sighted by S. Knight (USA) on April 13.17UT at magnitude ~14.0v. The report of the sighting was subsequently forwarded by phone to the AAVSO. ... SN 1991T. The galaxy NGC 4527 is an Sb(s)II type galaxy with an apparent Blue magnitude of 11.32 (Shapley-Ames, 1981). ... An analysis of this event utilizing visual observations by amateurs, plus a light curve is presented.. ... THE LIGHT CURVE: . ... ISN SN 1991T web page . ...

... Here are some general thoughts about the role of Mark5 recording in pulsar experiments. Pulsar work with the Mark5 Backend: Advantages: Flexibility: Set frequency time resolution after observations, enabling multiple analyses of the data. ... We can use the Mark5 recorders to gauge stability of the other pulsar timing backends: at multiple telescopes, and multiple epochs). ... The properties of these features changes as the scattering medium changes on day-month time scales. ...

... Observing . ... Solar Observing . ... April 3 (SUN) - Solar Observing, Central Park , Manhattan . ... APRIL'S SKY . ... Lecture Series at the American Museum of Natural History The Amateur Astronomers Association is proud to present an astronomy lecture series from October through May each year for our members and the .. ... The€аAmateur Astronomers Association of New York€аwas organized in 1927 to promote the study of Astronomy, emphasizing its cultural and inspirational value. ...

Emission Line Diagnostics in a ``No UV Bump'' Quasar PHL909 Smita Mathur, Belinda Wilkes, Martin Elvis and Jonathan McDowell Abstract PHL909 is a quasar with unusually low ultraviolet luminosity (blue bump strength C UV=IR = \Gamma0:20 compared to an average value of 0:4 (McDowell et al. ... The intrinsic continuum of PHL909 ( i.e. as seen by the BELR ) may thus be similar to the `standard' continuum, with a big blue bump, reddened along the line of sight. ...

... In order to compare the number of different evolutionary stages obtained and X-ray luminosity of the chosen X-ray sources with the observed galactic values we use the sum of C/O+O/C , where C and O are the calculated and observed values of a given binary type, respectively. If we make comparison for a number of different binary species (for example, we compare the number of CV, number of X-ray pulsars,   total X-ray luminosity of LMXB, etc.), we write this criterion in the form: . ...