... Tonight's Sky . ... Observing . ... Gravitational wave search provides insights into galaxy evolution and mergers . ... Turbulent, high-energy sky keeps NuSTAR busy . ... In fact, it was so bright that NuSTAR and other telescopes changed their observing cadence to spend more time studying this galaxy. ... Only registered members of Astronomy.com are allowed to comment on this article. ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ...