This appears to be lava in the act of erupting from Brimstone Pit. It is not glowing red, like in Hawaii, because this lava is more viscous — it is coming out very slowly and immediately forms a crust. But it is clearly degassing intensely, and small pieces of lava are spilling off as it expands. This looks very similar to the view when lava enters the ocean on the coast of Hawaii, even though the process is quite different here (and we are 560 m underwater!). Video courtesy of Submarine Ring of Fire 2006 Exploration, NOAA Vents Program.

Related Links

Submarine Ring of Fire 2006

Submarine Ring of Fire 2006: April 24 Log

NOAA Ocean Explorer Gallery