While some surveys simply look to see what’s there, others specifically target one kind of an object or another and then look for trends in those objects. Using the Atacama Large Millimeter/submillimeter Array (ALMA), a team of researchers led by Lucy Ziurys looked at five planetary nebulae to see where they kept their molecules. 

Planetary nebulae are formed when stars like our Sun die. As they run out of fuel they can use for nuclear fusion, their core collapses into a white dwarf while their outer layers are exhaled. In visible light telescopes, we see hot gas with green coming from oxygen and red from hydrogen. We also see dark bands where either there is no material or where there is material that is too cold to shine in visible light.

With ALMA, we see colors redder and cooler than what our eyes can see. Instead of the light from hot atoms, ALMA caught the light from cool molecules and found that those molecules lurk in the dark places of planetary nebulae. This hints that the hot structures we’re used to seeing are shaped by cooler, denser clouds that ALMA can reveal. This work is just starting, with just a handful of nebulae so far observed, but this is an important piece of the puzzle for understanding how planetary nebulae end up with such wild shapes.

More Information

The University of Arizona press release