A new study in the journal Science examined the contents of more than 500 million Twitter messages sent in 84 countries over the course of two years, looking for signs of good moods and bad. It found what a lot of us could tell by looking at our own lives.
Optimism is reborn with each new day and slowly erodes as we work, study and go about our quotidian affairs. Our mood lifts as we head home to friends, family, entertainment and beer. Our outlook tends to be sunnier on weekends. And speaking of sun, when it starts to pile up in the spring or disappear in the fall, that affects our mood, too.