It’s 2019, And Astronomers Just Discovered a New Type of Strange, Pulsing Star

A star with an interrupted death sequence could be the progenitor of a type of star that’s totally new to science. Astronomers have just discovered type of very small, very hot star that brightens and dims every few minutes as its outer layers try to maintain equilibrium.

The stars have been named hot subdwarf pulsators, and they could be related to another type of rare and mysterious recently discovered star: the blue large-amplitude pulsator.

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Tau.Neutrino said:

It’s 2019, And Astronomers Just Discovered a New Type of Strange, Pulsing Star

A star with an interrupted death sequence could be the progenitor of a type of star that’s totally new to science. Astronomers have just discovered type of very small, very hot star that brightens and dims every few minutes as its outer layers try to maintain equilibrium.

The stars have been named hot subdwarf pulsators, and they could be related to another type of rare and mysterious recently discovered star: the blue large-amplitude pulsator.

more…

From link, i has heard of of the Palomar Oschin telescope (one of the smallest telescopes at Palomar, but enormously successful) and the Palomar Transient Factory, but the ZTF is new to me.

The Zwicky Transient Facility (ZTF) is a new time-domain survey that had first light at Palomar Observatory in 2017. Building on the highly successful legacy of the Palomar Transient Factory (PTF), ZTF will use a new camera with a 47 square degree field of view mounted on the Samuel Oschin 48-inch Schmidt telescope. ZTF’s extremely wide field and fast readout electronics will enable a survey more than an order of magnitude faster than that of PTF.

Agree that the mechanism by which a red giant may lose its outer shell of hydrogen is completely unknown.