At day 4 we’re nearly half way through the event. Hope you’re all chatting, asking and voting!

Today’s highlights in the Crystallography Zone:

• Giant crystals:

What is the biggest crystal you have seen?

• The progress of crystallography research…

finleye : is research progressing in the crystallography world

susanateixeira : Well, if I can find what is behind taste we can change the way we eat and make better use of our resources…. or if I can find what stopps potatoes and strawberries rotening we can stop crops going from waste.

• Clicking joints:

shrinab : does clicking your joints help give you arthritis?

davidbriggs : No it doesn’t! Lots of people think it does but that’s not true! It might damage your tendons, but it won’t give you arthritis.

lozzaf : isn’t clicking your fingers just the air making a noise?

davidbriggs : clicking your fingers is, but crunching your knuckles is the tendons shifting in the joints.

• And how the invention of the telescope has shaped the world…

If telescopes were never invented do you think the world would still be the same?