On 9th October 2020, amateur radio balloons were launched from schools across the USA each with APRS on either 144.390 MHz FM or 144.340 MHz FM. They are heading East around the world

The 11 balloons seem to be floating at an altitude just above 20,000 feet (6-7,000m) and it's expected they will take a few days to cross the Atlantic.

One of the balloons is KE0LYF-1 from Minnesota; its real-time track can be seen at

https://tracker.habhub.org/#!mt=roadmap&mz=4&qm=1_day&f=KE0LYF-1&q=!RS_*; or https://www.aprsdirect.com/sid/3340987/time/1440

Smithsonian event announcement with the balloons amateur radio callsigns - https://airandspace.si.edu/events/live-balloon-launch-across-america

A recording of the live stream - https://www.facebook.com/airandspace/videos/1936985526444386