  In 2016-2017, TUS, the world's first experiment for testing the possibility
of registering ultra-high energy cosmic rays (UHECRs) by their fluorescent
radiation in the night atmosphere of Earth was carried out. Since 2019, the
Russian-Italian fluorescence telescope (FT) Mini-EUSO ("UV Atmosphere") has
been operating on the ISS. The stratospheric experiment EUSO-SPB2, which will
employ an FT for registering UHECRs, is planned for 2023. We show how a simple
convolutional neural network can be effectively used to find track-like events
in the variety of data obtained with such instruments.
