Between 24 March and 5 June 2010, the Hyperion hyperspectral imager and Advanced Land Imager (ALI) on NASA's Earth Observing 1 (EO-1) spacecraft obtained an unprecedented sequence of 50 observation pairs of the eruptions at Fimmvörðuháls and Eyjafjallajökull, Iceland. This high acquisition rate was possible only through the use of data flow streamlined by using the autonomously operating NASA Volcano Sensor Web (VSW). The VSW incorporates notifications of volcanic activity from multiple sources to retask EO-1 and process Hyperion data to extract eruption parameters from high spatial and spectral resolution visible and short-wavelength infrared data. Physical changes in eruption style and magnitude were charted as the eruptions ran their course. Rapid data downlink and automatic data-processing algorithms generated a variety of products which are compared with estimates from ground-based observations and post-eruption in situ measurements. Estimates of effusion rate from heat loss measurements underestimate actual effusion rate (while still following broad eruption rate trends) but are closer to in situ estimates for effusive eruptions (Fimmvörðuháls) than explosive, ash-rich eruptions (Eyjafjallajökull). During the later stages of the 2010 eruption, VSW-generated products were rapidly delivered to end-users in Iceland to aid in the assessment of risk and hazard. The success of the VSW led to Icelandic Meteorological Office (IMO) in situ sensors being incorporated into the VSW, and in May 2011 an IMO seismic alert autonomously triggered EO-1 observations of a new eruption at Grímsvötn volcano. Finally, the VSW demonstrates an autonomy-driven, multi-asset, spacecraft retasking and data processing system that maximizes science return, a desirable capability for future NASA missions.