Publication Date:
2013-05-25
Description:
Dwarf novae are white dwarfs accreting matter from a nearby red dwarf companion. Their regular outbursts are explained by a thermal-viscous instability in the accretion disc, described by the disc instability model that has since been successfully extended to other accreting systems. However, the prototypical dwarf nova, SS Cygni, presents a major challenge to our understanding of accretion disc theory. At the distance of 159 +/- 12 parsecs measured by the Hubble Space Telescope, it is too luminous to be undergoing the observed regular outbursts. Using very long baseline interferometric radio observations, we report an accurate, model-independent distance to SS Cygni that places the source substantially closer at 114 +/- 2 parsecs. This reconciles the source behavior with our understanding of accretion disc theory in accreting compact objects.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Miller-Jones, J C A -- Sivakoff, G R -- Knigge, C -- Kording, E G -- Templeton, M -- Waagen, E O -- New York, N.Y. -- Science. 2013 May 24;340(6135):950-2. doi: 10.1126/science.1237145.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉International Centre for Radio Astronomy Research, Curtin University, Perth, WA 6845, Australia. james.miller-jones@curtin.edu.au〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23704566" target="_blank"〉PubMed〈/a〉
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
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Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
