Altieri’s Lens: A Rare Einstein Ring Discovered by Euclid

O’Riordan et al. discovered a rare Einstein ring, “Altieri’s Lens,” around NGC 6505 using Euclid data. The lensing galaxy, at redshift z=0.042, bends light from a background galaxy, forming a near-perfect ring. Detailed analysis reveals a low dark matter fraction and a heavier-than-usual stellar population, providing new insights into galaxy structure and evolution.