B737-800 and unidentified glider cross paths on IFR approach

A Boeing 737-800 on IFR approach to Bremen and an unidentified white glider passed in close proximity at ~1 370 m MSL; no damage, no injuries. Descending through ~1 370 m MSL, the airliner crew received a primary-target traffic advisory from approach control at 12 o'clock, two miles, and acknowledged the sighting; the glider crossed from right to left at roughly 105 degrees, with closest approach reported as ~670 m horizontal and ~60 m vertical (glider above). The event occurred in Class E airspace, where VFR traffic is not separated from IFR. The investigation was closed as a facts-only report; no probable cause was attributed.

1. IFR approach descending to ~1 370 m MSL: A Boeing 737-800 with 152 passengers and six crew was on an IFR flight from Trapani to Bremen, descending toward the final approach fix of RWY 27, cleared to ~1 220 m MSL.
2. Class E, no VFR separation: The event took place in Class E airspace, where IFR flights are separated from each other but not from VFR traffic; VFR flights need no clearance and no transponder below ~1 525 m MSL.
3. Conflicting traffic at 12 o'clock: The approach controller saw a primary target at the B737-800's 12 o'clock and, unsure it was an aircraft, passed a traffic advisory, refined shortly after to two miles.
4. ATC advisory; crew gains visual: The crew acknowledged and reported the traffic in sight; passing ~1 370 m MSL, they saw a white glider cross their path from right to left, about 60 m above.
5. Crossing ~670 m horiz, ~60 m vert: Radar showed the tracks crossing at about 105 degrees, closest ~670 m horizontally and ~60 m vertically with the glider above; no one was injured and nothing was damaged.