April 25, 2024

High-Speed Propeller Star Is Fastest Spinning White Dwarf – It’s the Size of Earth, but 200,000 Times More Massive

Record-breaking spin rate for a verified white dwarf star is observed by University of Warwick-led astronomers
Establishes the star as only the second magnetic propeller ever discovered, over seventy years because the first
Scientists combined the extremely sensitive HiPERCAM instrument with worlds biggest running optical telescope to make the finding

Artist impression of LAMOST J024048.51 +195226.9, the fastest spinning verified white dwarf and only 2nd ever magnetic prop known. Credit: University of Warwick/Mark Garlick

A white dwarf star that completes a complete rotation once every 25 seconds is the fastest spinning verified white dwarf, according to a team of astronomers led by the University of Warwick.
They have actually developed the spin duration of the star for the very first time, verifying it as an incredibly rare example of a magnetic prop system: the white dwarf is pulling gaseous plasma from a neighboring buddy star and flinging it into space at around 3000 kilometers per second.
Reported in November 22, 2021, in the journal Monthly Notices of the Royal Astronomical Society: Letters, it is just the 2nd magnetic prop white dwarf to have actually been identified in over seventy years thanks to a mix of effective and sensitive instruments that allowed researchers to see the speeding star.

The study was led by the University of Warwick with the University of Sheffield, and moneyed by the Science and Technology Facilities Council (STFC), part of UK Research and Innovation, and the Leverhulme Trust.
A white dwarf is a star that has actually burnt up all of its fuel and shed its external layers, now going through a process of diminishing and cooling over millions of years. The star that the Warwick group observed, called LAMOST J024048.51 +195226.9– or J0240 +1952 for brief, is the size of the Earth however is believed to be at least 200,000 times more huge. It belongs to a binary star system and its enormous gravity is pulling product from its bigger buddy star in the kind of plasma.
In the past, this plasma was falling onto the white dwarfs equator at high speed, supplying the energy that has actually provided it this dizzyingly fast spin. Put into context, one rotation of the world Earth takes 24 hours, while the equivalent on J0240 +1952 is a simple 25 seconds. Thats practically 20% faster than the verified white dwarf with the most comparable spin rate, which completes a rotation in simply over 29 seconds.
The rest will stream towards the stars magnetic poles. It collects in bright spots on the surface area of the star and as these turn in and out of view they trigger pulsations in the light that the astronomers observe from Earth, which they then utilized to measure the rotation of the entire star.
Lead author Dr. Ingrid Pelisoli of the University of Warwick Department of Physics said: “J0240 +1952 will have completed numerous rotations in the short quantity of time that people take to check out it, it is actually incredible. The rotation is so fast that the white dwarf should have an above typical mass just to remain together and not be torn apart.
” It is pulling product from its buddy star due to its gravitational impact, however as that gets closer to the white dwarf the magnetic field starts to dominate. This kind of gas is highly performing and gets a lot of speed from this procedure, which propels it far from the star and out into space.”
J0240 +1952 is among only 2 stars with this magnetic propeller system found in over past seventy years. Although product being flung out of the star was first observed in 2020, astronomers had not had the ability to confirm the presence of a rapid spin that is a primary ingredient of a magnetic propeller, as the pulsations are dim and too quick for other telescopes to observe.
To visualize the star at that speed for the first time, the University of Warwick team used the highly delicate HiPERCAM instrument, collectively operated by Warwick and the University of Sheffield with funding from the European Research Council. This was specially installed on the biggest operating optical telescope worldwide, the 10 meter diameter Gran Telescopio Canarias in La Palma, to record as much light as possible.
” These type of research studies are possible thanks to the special mix of the fast imaging capability of HiPERCAM with the largest collecting area on the planet supplied by GTC,” stated Antonio Cabrera, Head of GTC Science Operations.
Co-author Professor Tom Marsh from the University of Warwick Department of Physics adds: “Its only the 2nd time that we have actually discovered one of these magnetic propeller systems, so we now know its not a special occurrence. It establishes that the magnetic propeller system is a generic property that operates in these binaries, if the scenarios are right.
” The second discovery is practically as essential as the very first as you develop a model for the first and with the second you can evaluate it to see if that design works. This latest discovery has shown that the model works truly well, it forecasted that the star needed to be spinning quick, and undoubtedly it does.”
Recommendation: “Found: a rapidly spinning white dwarf in LAMOST J024048.51 +195226.9” by Ingrid Pelisoli, T R Marsh, V S Dhillon, E Breedt, A J Brown, M J Dyer, M J Green, P Kerry, S P Littlefair, S G Parsons, D I Sahman and J F Wild, 22 November 2021, Monthly Notices of the Royal Astronomical Society: Letters.DOI: 10.1093/ mnrasl/slab116.

A white dwarf is a star that has burnt up all of its fuel and shed its external layers, now undergoing a process of cooling and shrinking over millions of years. The star that the Warwick team observed, named LAMOST J024048.51 +195226.9– or J0240 +1952 for brief, is the size of the Earth but is believed to be at least 200,000 times more massive. It is part of a binary star system and its immense gravity is pulling product from its bigger buddy star in the kind of plasma.
The rest will stream towards the stars magnetic poles. It gathers in intense spots on the surface area of the star and as these rotate in and out of view they trigger pulsations in the light that the astronomers observe from Earth, which they then used to measure the rotation of the whole star.