RR Lyrae stars have long been considered unequivocal tracers of old (>10 Gyr) and metal-poor ($\mathrm{[Fe/H]}<-0.5$) stellar populations. First, because these populations are where they are readily f...

At just 25, Cecilia Payne-Gaposchkin applied quantum physics to a treasure trove of astronomical observations to show that stars are mostly hydrogen and helium.

NASA science faces record cuts. Take action to stop it—we'll show you how.

Gaia Data Release 3 (GDR3) contains a wealth of information to advance our knowledge of stellar physics. In these lecture notes we introduce the data products from GDR3 that can be exploited by the st...

Today's paper explores a binary quasar system that's full of mysteries!

As promised in last weeks post, we have another look at the old friend of the project, KH15D this week. In the two images above we compare the I-band light curves for the object for the observing seas...

On December 24th, AES Andes, a subsidiary of the US power company AES Corporation, submitted a project for a massive industrial complex for environmental impact assessment. This complex threatens the pristine skies above ESO’s Paranal Observatory in Chile’s Atacama Desert, the darkest and clearest of any astronomical observatory in the world [1]. The industrial megaproject is planned to be located just 5 to 11 kilometres from telescopes at Paranal, which would cause irreparable damage to astronomical observations, in particular due to light pollution emitted throughout the project’s operational life. Relocating the complex would save one of Earth's last truly pristine dark skies.