This beautiful picture was assembled using data that were collected primarily for very specific research purposes, as are many of the Hubble Pictures of the Week. The research conducted using these data included measuring the extent of ionisation in the jets being blasted out of the protostar buried within G35.2-0.7N. Ionisation is a process by which atoms or molecules become charged, often because they are in such a high-energy environment that they have lost some of their electrons (the tiny negatively charged particles that orbit nuclei in atoms and molecules). Protostellar jets are enormous collimated beams of matter that are ejected from protostars. Collimated simply means that the matter is ejected in parallel (column-like) streams, which in turn means that the jets do not spread out much, but extend out very far in relatively straight lines.
The visual result of the ejected matter is the glorious display visible in this image. Much of the nebula is dark, with light being blocked from Hubble’s view by the rich dust clouds that produce these massive stars. Near the very centre can be seen the location of the star and the jet of material it is emitting. The small, bright orange streak there is a cavity in the dust carved out by the ferocity of the jet as it streams towards us. By breaking through its dusty cocoon, the jet reveals light from the protostar, but there is still so much dust that the light is “reddened” to a fiery orange. The massive protostar lies at the very lower-left tip of this cavity.