In looking out at the universe, a lot of our energy goes into looking at the big stuff. Stars, galaxies, planets, and even asteroids aren’t all that small in the grand scheme of things. The thing is, all that stuff — it’s all built of gas and dust, and that dust is often the core bit of grit that structures formed around, like water drops forming on dust in the atmosphere.

We don’t talk about dust in detail very often because it is surprisingly complex. The most basic aspects of dust can be deeply confusing: things as simple as what’s its shape and why?

In new research, also presented at the AAS meeting, researcher Angela Speck considers this matter of shape. Carbon dust, for instance, can come in messy shapes that lack any clear structure. This is called amorphous dust. Well-structured – crystalline – dust is also found. In examining why dust has different structures, Speck noted that warm material can form amorphous dust, but as the dust cools, crystal structures can emerge. The crystal structure actually has a lower temperature, so cooling dust can rewarm as its structure changes from messing to symmetric.

Understanding that amorphous dust stores heat that can be released changes how we have to view structure formation. Now, as well as blocking starlight, we need to know that dust can reheat its surroundings.

It’s the little things – like dust – that ultimately affect so much.

More Information

UTSA press release