One star, two star, red star, blue star: an updated planetary nebula central star distance catalogue from <i>Gaia</i> EDR3

The central star of the Planetary Nebula NGC 6537

The fact that Space Telescope WFPC2 images of the planetary nebula NGC 6537 fail to show the central star is used to derive a limit to its magnitude: it is fainter than a magnitude of 22.4 in the visible. This is used to derive a lower limit to the temperature of the star. The Zanstra temperature is at least 500 000 K. The Energy Balance temperature is found to be consistent with this value, as...

generalization of star-mesh transformation

it is well know that any three impedances or admittances connected into each other in a star form can be easily transformed to a new three impedances or admittances connected into each other in a mesh form. in this paper a generalization of this fact is established and it is shown that in an n + 1 node network which is connected in a form it is always possible to eliminate the center node and o...

antioxidant property of two star thistles (centaurea) from iran

Luminous Red Variable Star

We report photometry and spectroscopy of the evolution of Nova Sagittarii 1994 #1 (V4332 Sagittarii) during outburst. We compare the photometric and spectral evolution of this outburst to known classes of outbursts – including classical novae and outbursts occurring on symbiotic stars – and find this object does not conform to any known class of outburst. The closest match to the behavior of th...

Binary Star Measurements with the Star re

Four binaries, 10 UMa, UMa, 81 Cnc, and UMa, were observed with adaptive optics on the 3.5m telescope at the Starrre Optical Range on March 24, 1998, in order to investigate the relative photometry produced by adaptive optics within the isoplanatic patch. Iterative Blind Deconvolution (IBD) and Parametric Blind Deconvolution (PBD) techniques were used to post-process the data, and produced cons...