Hubble is scouting the sky for the Roman telescope — two generations of observatories, working as a team

NASA has released a Hubble Space Telescope image from October 22 with a job bigger than its beauty: a sweeping barred galaxy fills the frame, but the real target is a small gravitational lens at the bottom right — light bent by gravity around a foreground galaxy. Hubble is gathering many such lensing images to prepare the ground for the Nancy Grace Roman Space Telescope, its successor, which will use them to study dark matter and map the cosmos at far greater scale. The old telescope, in other words, is drawing the treasure map; the new one will dig.