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<i>Scientists are studying the violent outburst of a dead star as it tries to fire back into life. <br /><br />The white dwarf star in the Ophiuchus constellation has exhausted its own nuclear fuel but is now stealing it from a neighbouring giant. <br /><br />Every 20 years or so, it gathers sufficient material to explode with enough intensity to be seen from Earth with the naked eye. <br /><br />The so-called recurrent nova event has now flared up six times in 108 years. <br /><br />"It's a runaway nuclear bomb, basically, that has gone off on the surface of the white dwarf star," said Mike Bode.<br /><br />-------<br /><br />The white dwarf star is about 5,000 light-years from Earth and is probably little bigger than our own planet, having burnt all its hydrogen and shed its outer layers. <br /><br />It is now extremely dense and its strong gravity can pull gas off a companion, red giant star. The two objects orbit each other every 455 days. <br /><br />What is very unusual in this arrangement is that the red giant is losing enormous amounts of gas in a wind that envelops the whole system (referred to as RS Ophiuchi, or RS Oph). <br /><br />As a result, when the episodic thermonuclear explosions let go, they do so "inside" the companion's extended atmosphere. <br /><br />"When this thing goes bang, it blows material out into the wind and sets off shocks that are at more than 100 million degrees, nearly 10 times the core temperature of our Sun," Professor Bode told the BBC News website.</i> <br /><br />Link <div class="Discussion_UserSignature"> <strong><font color="#3366ff">Made weak by time and fate, but strong in will to strive, to seek, to find and not to yeild.</font> - <font color="#3366ff"><em>Tennyson</em></font></strong> </div>