The Northern Star, whose vibrations were thought to be dying away, appears to have come to life again.
An international team of astronomers has observed that vibrations in the Pole star, which had been fading away to almost nothing over the last hundred years, have recovered and are now increasing. And the astronomers don’t know why.
The discovery will be announced during the “Cool Stars 15” conference at the University of St Andrews. Dr Alan Penny from the School of Physics and Astronomy will present results of the recovery to around 350 international delegates at the meeting that runs from July 21-25.
The astronomers were watching Polaris in the expectation that they would catch the star switching off its vibrations completely when they made the surprising observation of its revival.
Dr Penny explained, “It was only through an innovative use of two small relatively unknown telescopes in space and a telescope in Arizona that we were able to discover and follow this star’s recovery so accurately.”
Team leader, Dr Hans Bruntt of the University of Sydney, had been using a small telescope attached to NASA’s now defunct infrared space telescope (WIRE) to study the star for a short period of time. He knew Dr Penny was using a device known as the SMEI space camera – predominately employed to watch matter being ejected from the Sun – to do long-term monitoring of stars. When the SMEI data were analysed this recovery of Polaris was seen, and could also be traced in the WIRE data.