The star HD 45166 has puzzled astronomers for a century . Dr Tomer Shenar arrive so fascinated with its universe that he has spent years essay to explicate its nature . In the process , he may have work out an even bigger mystery : the source of the cosmos ’s most knock-down magnets .
HD 45166 is aWolf - Rayet star . These atomic number 2 - rich star are the hottest category of star we have found , in HD 45166 ’s case , almost 10 times as blistering as the Sun . Their immense heat means that despite being exceptionally rare , they make an outsize share to the universe ’s stock of heavier component .
Being so extreme , Wolf - Rayet genius have a peck of unexplained features , but HD 45166 has some particularly curious properties , including a spectral signature unlike any other .
Artist’s impression of HD 45166, showing its invisible, extraordinarily powerful magnetic fields. The star is so hot most of its light is emitted in the ultraviolet.Image Credit: ESO/L. Calçada
“ This star became a bit of an obsession of mine , ” The University of Amsterdam ’s Shenar said in astatement . “ I recall experience a Eureka instant while reading the literature : ‘ What if the champion is magnetic ? ’ ”
Shenar and colleague used the Canada - France - Hawaii Telescope to study HD 45166 in unprecedented detail , seeking the polarisation and break up ghostly contrast that argue impregnable magnetic fields . Combined with archival observation from other instruments , they have reveal previously unknown features about the star , most significantly that it has a magnetic field of 43,000 Gauss .
By comparison , the Earth ’s magnetic field is about half a Gauss and a electric refrigerator attraction is about 50 Gauss . You really would n’t need to be in the vicinity of this thing if you have a pacemaker .
Nevertheless , this is far from a record . Magnetars , a rarefied subset of neutron stars , have magnetic William Claude Dukenfield of hundreds of trillion Gauss , a figure completely out of keeping with the quietus of the universe . Until now , astronomers have not been able to explain how these astounding fields form , and why some neutron stars are so magnetic while others are not , but Shenar call back HD 45166 is the clew .
Like other Wolf - Rayet genius , HD 45166 is monolithic enough that it will eventually become a supernova . Indeed , that time is not far off , astronomically utter , since it has burned through most of its H , which is why it is so helium - rich . Once it has finished fusing much of its helium into other elements , its core will collapse and explode , leaving a neutron hotshot behind .
Being far denser than the star from which it come ( and indeed denser than anything other than a bootleg hole ) , the neutron star ’s Brobdingnagian magnetised flux will create a orbit swell than the one HD 45166 presently has . Quite likely , that same amount of magnetics packed into a tight space will be sufficient to produce a magnetar . It might seem strange that a magnetized field would last an explosion as knock-down as a supernova undisrupted , but that is what astral phylogeny models evoke will occur .
This still leave the question of why some sensation are so charismatic to start with . HD 41566 ’s arcanum may lie in Shenar ’s suspiciousness it was form from two stars that germinate in a very tight cranial orbit , passing their outer layers back and forth until their orbits decay , and they merge .
This is the first metre a monolithic helium star has been found to be magnetic , and could sparkle a race to see whether it is as unusual as it seems . “ It is exciting to uncover a new type of astronomical object , ” Shenar enounce , ” specially when it ’s been conceal in plain great deal all along . ”
In the discovery process , Shenar found some other interesting things about HD 45166 . Although already know to be part of a binary system , close reflexion revealed it revolve more than 50 times further from its companion than previously believe , rule out the possibility their interactions strip off its outer layers . It ’s also quite a bit lighter than anticipated , around twice the mass of the Sun . That ’s singular , because all other Wolf - Rayet stars are at least 8 solar multitude .
HD 45166 is around 3,000 light years away , far enough to be whole safe when it goes supernova , probably in a few tens of thousands of twelvemonth , but close enough to give us a peachy show .
The finding are write inScience .
