As many planets as there are grains of sand on this planet?!? Firstly I bet scientists haven’t got a clue about how many grains of sand there are – secondly they CERTAINLY haven’t got a clue about how many planets there are. They have detected about 4 planets all gassy and bigger than Jupiter but are still just too crap to be able to see them; they just can note the gravitational pull on the planets host star (they can see stars wobbling slightly).
I have been in London where the hottest place yesterday was where I was 36.4c (Enfield and Southgate) and today on my way back I passed Heathrow on the m25 as it reached 37.9c (100f) a new all British record don’t ya know. I had the window wide open but it was just blowing hot air at me!