Astronomical Observatory

A complete correspondence between the Newman–Penrose and 1+1+2 formalisms

Abstract We establish a correspondence between the Newman–Penrose and 1+1+2 semitetrad covariant formalisms by expressing all Newman–Penrose spin coefficients, Ricci scalars, and Weyl scalars in terms of the scalar, vector, and tensor variables of the 1+1+2 decomposition. In addi...

Validation and Spin of the Bright Part of Gaia DR2 and DR3

ABSTRACT The Gaia Data Release 3 (DR3) is an important step in the realization of the future Gaia reference frame. Ideally, across G magnitudes from 3 to 21, the Gaia DR2 and DR3 objects with their positions (, ) and proper motions (, ) should be expressed in a nonrotating refere...

eRASSU J043115.8-711730 The first pulsating symbiotic super-soft X-ray source in the Magellanic Bridge

Abstract The Magellanic Bridge stellar population is a relic of the tidal interaction between the Large and Small Magellanic Clouds. A comprehensive view of the evolution of the Bridge stellar population requires probing the compact remnants of stellar evolution, otherwise hidden...