What has Juno found on Jupiter? Part I – Water and weather

One of Juno’s findings has been some measurements of the Great Red Spot – a giant Jovian storm that could fit three Earth-sized planets inside it. Although Juno has the power to image up to 350 km deep into the Jovian atmosphere, it turns out that the Great Red Spot is deeper than this. Measurements of its temperature show that, for the first 80 km, it is cooler than the surrounding atmosphere, and below that, it’s warmer. We don’t know why, but it could be linked to how the storm started, and whether it's permanent or will disappear with time.

 

The Great Red Spot has been observed for over 300 years now. It's so large it could accommodate three Earth-sized planets! Wikimedia Commons

Moving moss

In glacial landscapes across the world, small balls of moss form, oval in shape, and tumble simultaneously as the glaciers melt, as if moving in a herd.

Known as “glacier mice”, these moss balls are understudied, but recently researchers have taken notice of them and their weird, herd-like behaviour^[1]. This has led to all sorts of questions and a couple of published papers on the phenomenon, such as...

How do they form?

Researchers have theorised that the moss balls form through “nucleation” at rough points on the glacier surface – just as crystals start growing on impurities in their containers. First, one crystal or drifting moss fragment attaches, and then others attach onto that, gradually coming together to make the shape of the final structure. It’s not clear how this always leads to oval balls, and none of them are round, but it does generally make sense as a theory.