The structure of magnetic field and the distribution of dust in space is revealed by high-precision polarisation measurements. The figure shows the degree and direction of polarisation of more than ...

As a result, the most accurate space maps are those that rely on orbital observations backed by Earth-based telescopes, whose radio data enable the coordinates to be corrected. An active galactic ...

Our galaxy's gravitational field limits the accuracy of astrometric observations of distant objects. This is most apparent for objects that are obscured behind the central regions of the galaxy and ...

“The definition of the Galactic coordinate system was announced by the IAU Sub-Commission 33b on behalf of the IAU in 1958. An unrigorous transformation was adopted by the Hipparcos group to transform ...