Exception UnsupportedClassVersionError

Como resolver esse erro? Acredito que compilei com o Java 10 e agora estou usando o Java 8.
Exception in thread "main" java.lang.UnsupportedClassVersionError: br/com/alura/curso/java/DatasComHora2 has been compiled by a more recent version of the Java Runtime (class file version 54.0), this version of the Java Runtime only recognizes class file versions up to 52.0 at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(Unknown Source) at java.security.SecureClassLoader.defineClass(Unknown Source) at java.net.URLClassLoader.defineClass(Unknown Source) at java.net.URLClassLoader.access$100(Unknown Source) at java.net.URLClassLoader$1.run(Unknown Source) at java.net.URLClassLoader$1.run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)

Screenshot_2 Screenshot_3

Ou você recompila com Java 8 ou utiliza o parâmetro -target=1.8 ao compilar no Java 10.

E como faço isso?

Edit: resolvido! Obrigado pela ajuda, @staroski
Solução que encontrei: (Eclipse) Window > Preferences > Java > Installed JREs > Add.