areas. As a result, there's a simple relationship: the more sunspots, the more solar output reaches Earth.

Normally, sunspots come and go with the 11-year long solar cycle—more during peak activity, less during the Sun's quieter times. But superimposed on that cycle are longer-term trends in activity that we don't understand very well. For example, solar activity has been trending downward since the 1980s, and it's not entirely clear why. But it's still much more active than it was during a roughly 70-year period around 1700, when the Sun experienced what's called the Maunder Minimum, with very few sunspots visible the entire time.

That period happened to coincide with the Little Ice Age, which saw global temperatures dip and glaciers advance, with Europe experiencing notably colder weather. The lack ofLast updated on .From the section Football

Gareth Bale's goal against Swiss side Basel was his second of the season for Real Madrid

Gareth Bale starred as holders Real Madrid thrashed Swiss side Basel to begin the defence of their Champions League title in impressive style.

After a Marek Suchy own goal had put Real ahead, Wales winger Bale smartly lobbed the keeper before finishing.

Bale set up Cristiano Ronaldo to tap in, James Rodriguez hit a fourth and Karim Benzema swept in a late fifth. Derlis Gonzalez scored for Basel.

Elsewhere, last season's finalists Atletico Madrid lost 3-2 at Olympiakos.

Champions League group-stage facts Cristiano Ronaldo has scored 53 goals in 52 Champions League appearances for Real Madrid Atletico Madrid conceded three times on Tuesday, the same amount as during their entire Champions