Overview

• The peer-reviewed study by E. Poggio and colleagues, published in Astronomy & Astrophysics, uses Gaia data on young giant stars and classical Cepheids to trace the structure.
• The feature spans roughly 30,000 to 65,000 light-years from the galactic center and displaces stars vertically by up to about 650 light-years.
• Gaia’s velocity measurements show the stars’ vertical motions are offset from their vertical positions, a pattern expected for a traveling wave.
• The team cites a past encounter with a dwarf or satellite galaxy as a plausible cause, while noting the origin remains unconfirmed and any link to the smaller Radcliffe Wave is uncertain.
• ESA says Gaia’s forthcoming Data Release 4, expected in December 2025, will deliver improved positions and motions to refine maps and test formation scenarios.