It is normal for attention to wander during mindfulness meditation. Simply note that your thoughts have wandered and, without judging this, try to shift your attention back to your mindfulness practice.
Rosette Nebula (NASA, Spitzer, This infrared image shows the Rosette nebula, a star-forming region more than 5000 ly away in the constellation Monoceros. Lurking inside this nebula are so-called 'danger zones'. These zones surround super hot stat