Nachrichtenheute journalheute journal, 2nd of June 2023Nachrichten | heute journal: heute journal, 2nd of June 202302.06.2023 | 19:44 UhrToday’s topics: Alternatives to the heat pump - discussion on the expansion of district heating; Concern about military secrets – German pilots train the Chinese; Research on the red planet – 20 years of the European Mars mission