A brand new sort of star will be the answer to a cosmic thriller. After a century of examine, astronomers have lastly labored out why a star known as HD 45166 appears so unusual, and it could possibly be the important thing to understanding the place curious stars known as magnetars come from.
HD 45166 is situated in a binary system about 3000 gentle years away and is a kind of object known as a Wolf-Rayet star, also called a helium star as a result of it has blown away its outer layers of hydrogen to disclose the underlying helium. Nevertheless it has by no means appeared fairly like some other Wolf-Rayet star we’ve ever seen. “This star was recognized to be bizarre for about 100 years,” says Tomer Shenar on the College of Amsterdam within the Netherlands. “It didn’t make any sense – it actually contradicted theories, so it deserved extra scrutiny.”
Shenar and his colleagues have now made a sequence of recent observations of the star, digging into the spectrum of its gentle to study extra about the way it works. They discovered that it has an awfully highly effective magnetic discipline, stronger than that of some other star of its dimension that has been measured.
The outflows of fabric that make HD 45166 look so unusual are most likely really trapped in its magnetic discipline, not flowing away like in regular Wolf-Rayet stars. “What you’d see up shut is generally materials trapped in arcs going between the poles of the star and colliding within the center,” says Shenar. “You’d see this thick ball of gasoline, and typically piercing by way of this you’d see the precise star.”
These highly effective fields imply that when this star collapses in on itself in just a few million years, it should probably grow to be a magnetar, that are neutron stars with the strongest magnetic fields within the universe. About 10 per cent of neutron stars are magnetars, however how precisely they kind has been a thriller for many years. If stars like HD 45166 do finally flip into magnetars, that thriller is lastly solved.
The subsequent step for Shenar and his group is twofold: by persevering with to watch the binary system for just a few extra years, they may get a greater deal with on the star’s properties and therefore its eventual destiny. Additionally they plan to seek for extra of those magnetised helium stars – their calculations point out that there ought to be a whole lot in our galaxy. If they will discover extra at totally different phases of stellar evolution, they could lastly have the ability to nail down how magnetars actually kind.