To their surprise, an international team of researchers has discovered a giant and extremely faint stream of stars between galaxies. Streams were already known in our own galaxy and in nearby galaxies, but this is the first time that a stream runs between galaxies. It is the largest stream detected to date. The astronomers publish their findings in the journal Astronomy and Astrophysics.

An international team of scientists, with participation by researchers at the Instituto de Astrofisica de Canarias (IAC), has discovered a very large, but thin, stream of stars in the Coma cluster of galaxies. This is the largest stream of stars detected until now, and the first to be found in a cluster of galaxies. This finding, which is published in the journal Astronomy and Astrophysics, was made using observations taken with the William Herschel Telescope (WHT) at the Roque de los Muchachos Observatory (Garafia, La Palma, Canary Islands).

Astronomers have discovered an extremely large and faint stream of stars in the Coma galaxy cluster. This is the largest stellar stream detected to date and the first of its kind found in a galaxy cluster. This discovery, published in the journal Astronomy & Astrophysics, has been possible thanks to observations made using the William Herschel Telescope (WHT).

Un equipo cientifico internacional, en el que participan las investigadoras del Instituto de Astrofisica de Canarias (IAC) Cristina Ramos Almeida, Patricia Bessiere y Giovanna Speranza, ha descubierto que los cuasares, uno de los objetos mas brillantes y energeticos del Universo, se encienden principalmente por fusiones entre galaxias.

Astronomers from Spain and Romania have scrutinised two distant trans-Neptunian object candidates, identified by automated software analyses of data from NASAs TESS mission. They used PF-QHY, a CMOS camera mounted at the renewed prime focus of the William Herschel Telescope, and could not recover these objects.

Following the Announcement of Opportunity ING issued on 21 March 2021, for WHT service-mode prime-focus imaging observations during April and May, we now extend this opportunity, and invite further applications for observations.

During the integration of WEAVE at the WHT, an opportunity has arisen to offer service-mode imaging with a camera (the QHY) mounted behind the new WEAVE prime-focus corrector, during April and May 2021.

This image of an unusually-close conjunction of Jupiter and Saturn was obtained on 21 Dec 2020, during tests of the new optical corrector at the prime focus of the William Herschel Telescope (WHT). The image is a composite of exposures taken with a CMOS camera, through blue, green and red filters.