The factors that allow for life on earth are so finely tuned as to be awe-inspiring. If, for instance, gravity was 20% more powerful, and the attraction of positively-charged protons to negatively-charged electrons was constant, insects would need much large legs to support themselves. Animals larger than insects could not exist. And if gravity were a little weaker, the number of atoms needed to make a star or planet would be a billion times less. Galaxies would form much more quickly and be much more densely packed. The orbits of planets would thus be unstable — they would be constantly pulled hither and yon by the gravity of passing stars. Stars would exist for periods of time a million times shorter. Instead of living for 10 billion years, a star would live for about 10,000 years. 
- Martin Rees, Just Six Numbers

The forces that allow life are indeed mysterious. It is hard to keep that in perspective as we go through life, but when I do try, I live with gratitude and awe.

. . .

Journal question:

What are you missing that, if paid attention to, would add a deeper sense of appreciation for the gift, the mystery, of life?