White Dwarf:
An international team has reported a unique phenomenon in a white dwarf about 1,400 light years from Earth. They saw the white dwarf lose its brightness in 30 minutes.
- These gaps in brightness have been previously reported but the process usually takes place over a period of several days to months.
- The team observed the phenomena using NASA’s Transiting Exoplanet Survey Satellite (TESS).
- The white dwarf is part of a binary system called TW Pictoris, where a star and a white dwarf orbit each other.
- The two objects are so close to each other that the star transfers material to the white dwarf.
- As this material approaches the white dwarf it forms an accretion disk or a disk of gas, plasma, and other particles around it. TW Pictoris is located in the Pictoris constellation, and the binary system is about 1400 light years from us.
- The team notes that a process called magnetic gating may be at play. This happens when the magnetic field is spinning so rapidly it creates a barrier disrupting the amount of food the white dwarf can receive.
- The team hopes that this discovery will help us understand the physics behind accretion – how black holes and neutron stars feed material from their nearby stars.
- A typical white dwarf is half the size of our Sun and has a surface gravity 100,000 times that of Earth. Using the Hubble Space telescope and Transiting Exoplanet Survey Satellite (TESS), astronomers have identified several white dwarfs over the years.
