Using the data obtained by the Five-hundred-meter Aperture Spherical radio Telescope (FAST), a research team led by Prof. PAN Zhichen and Prof. LI Di from the National Astronomical Observatories of the Chinese Academy of Sciences (NAOC) discovered an eclipsing binary millisecond pulsar in Globular Cluster (GC) Messier 92 (M92).

Named as PSR J1717+4307A or M92A, it is the first pulsar known in M92, with a spinning period of 3.16 ms and a dispersion measure (DM) of 35.45 pc cm-3. Follow-up observations showed that this binary system is in a circular orbit with an orbital period of 0.2 day and a radius of 120 thousand kilometers. The companion is a 0.18 solar mass star, evolving to be a sub-giant.

Due to the compactness of the orbit, materials from the companion are being swallowed by the pulsar. Such a binary system is nicknamed a 'redback' spider. Like this type spider that the female ones tend to eat their companions, the pulsar tends to accrete the mass from the companion.

Since the discovery of the first pulsar in 1967, thousands of pulsars have been found in our Galaxy. While some are located in the Galactic plane, we've also observed a population of pulsars in GCs that orbit the Milky Way.

These pulsars are a useful tool for probing a very different environment: the dense stellar cores consisting of stars as old as 10 billion years. To date, there are 157 pulsars discovered in 30 GCs.

M92A was first detected on October 9, 2017, during the commissioning of FAST. With more than twice the collecting area of that of the Arecibo Telescope in Puerto Rico, more discoveries are expected from FAST and they will improve our understanding of the pulsar population in the Milky Way and of related astrophysics, such as massive stellar evolution and equation of state of condensed matters.

This work was published in Astrophysical Journal Letters on Mar. 19, and it was highlighted by the American Astronomy Society (AAS) Nova site on April 17, 2020.

Research paper

Related Links
Five-hundred-meter Aperture Spherical radio Telescope (FAST)
Stellar Chemistry, The Universe And All Within It

Tweet

Thanks for being here; We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain. With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords. Our news coverage takes time and effort to publish 365 days a year. If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor $5 Billed Once credit card or paypal		SpaceDaily Monthly Supporter $5 Billed Monthly paypal only

Large scale survey telescope to be built in northwest China
Xining, China (XNA) Apr 24, 2020
Chinese experts will build a survey telescope with wide field and high resolution in Lenghu (Cold Lake) Town, in northwest China's Qinghai Province, sources here said. On April 16, the University of Science and Technology of China (USTC) signed a cooperation agreement with the Haixi Mongol and Tibetan autonomous prefecture in Qinghai province. They plan to build the telescope on top of Saishiteng mountain near the Lenghu Town, famed for being China's "Mars Camp" due to its eerily eroded desert lan ... read more