Nebulae are an elemental node in the Runespan that allows players to draw cosmic runes and astral runes from it. They are found on the middle and upper floors. It requires level 40 Runecrafting and gives experience in cycles of 63.8 if a cosmic rune is siphoned and 85.6 experience if an astral rune is siphoned, though occasionally will also give 2 experience when a failed siphon is performed.
Unlike creatures, players do not receive any rune essence when a node is depleted of its energy.
- The nebula is among the few nodes which players choose to siphon all the way to 99 Runecrafting. Experience gained from nebulae becomes worthwhile at level 75 Runecrafting. Anything below 75 will be noticeably slower, so it is recommended to obtain this level before training on these.
- A permanent but non-interactive version could be found on an experiment plinth on the 1st floor[UK]2nd floor[US] of the Wizards' Tower along with similarly non-interactive versions of a Chaotic cloud, Rock fragment, fireball, shifter, and cyclone.