Welcome along, Explorer. My name's Dan. It's the part of the week where we're a little bit bored of life down here on blue-green planet Earth.

So let's see what else is out there, shall we?

And search for some science secrets across the universe. It's the Fun Kid Science Weekly.

And this week we're settling the ultimate

earth-sized question. It's grain of sands versus drops of water. Surely, surely, surely,

there's much, much more water than there is sand. The earth is over 70% water. The Mariana

trench in the Pacific is deeper than Mount Everest. So surely there is far, far, far much more

water on the earth, and therefore more drops than there is sand. But now I'm going to take you

through the maths, and it's much, much closer than I originally expected.

Also, you can hear about something so dangerous a beam of light can make it explode.

And we're talking all about rockets of the future because they won't run on fuel.

They'll run on plasma.

The energy source, which heats up our own sun is plasma fusion.

And so far nobody has figured out how we can use fusion energy within a plasma rocket

for the purpose of creating propulsion systems that might take us even outside of the solar system and out

into the stars.

That's all on the way in a brand new Fun Kid Science Weekly.

Let's start with your science in the news then.

And a critically endangered spider not seen in the UK for 40 years has been rediscovered.

Alluonia Albimana, which was last recorded in the UK in 1985, was found at the National Trust's

Newtown National Nature Reserve on the Isle of Wight. It's been missing for 40 years and it's come back.

It was spotted in a remote overgrown area of the reserve that you can only get to by boat

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