The Pavlof Volcano in Alaska spews hot ash into the sky in May this year. (REX/Jesse Allen/Robert Simmon/NASA
Another image of the Pavlof volcano erupting in Alaska in May 2013. (REX/NASA/Robert Simmon/GM Gentry)
The Sarychev Volcano in Russia spews a huge ash cloud upwards in June 2009. (Rex/NASA)
The Chaitén Volcano, Chile, in May 2008. (REX/Jesse Allen/NASA/GSFC/METI)
A dramatic aerial image of the Manam Volcano, Papua New Guinea, in June 2010. (REX/Jesse Allen/NASA)
The Shinmoe-dake Volcano in Japan, in January 2011. (REX/Jeff Schmaltz/MODIS/NASA-GSFC)
The Sakurajima Volcano in Japan sends smoke 5km into the air last month. (REX/NASA/Jesse Allen/Robert Simmon)