The active volcano, whose alert level is at its highest, erupted four consecutive times on Tuesday morning.
The satellite data usually isn't accessible, since commercial companies help gather it, but for emergency management, they're making an exception.
A huge ash cloud forced the closure of Bali's Ngurah Rai International Airport on Monday for 24 hours.
Indonesia's Disaster Mitigation Agency set up an exclusion zone and ordered people to "immediately evacuate."
But authorities say they can't predict exactly when the blast will happen.
The U.S. is advising against any visits to the volcano, warning that an eruption could disrupt flights.