We will have the 24th online colloquium “Extreme Universe Colloquium” on April 19th (Fri) 17:00 (JST). The speaker is Prof. Robert Koenig ( Technical University of Munich). For details, please refer to the poster. If you have not registered yet, please register at our online event website at least three days prior to the colloquium. (It is not necessary to register again if you have done it already.)