what was this disaster's magnitude?
6.7
2006 Kiholo Bay earthquake
The 2006 Kīholo Bay earthquake occurred on October 15 at with a magnitude of 6.7 and a maximum Mercalli intensity of VIII ("Severe"). 
what is the tallest mountain in the world from base to summit Mauna Kea where is it located? Hawaii, United States what kind of activities are recorded in this mountain? Hunting, Birdwatching is there an observatory? Yes - The Mauna Kea Observatories (MKO) what exactly are these observatories? A number of independent astronomical research facilities and large telescope observatories that are located at the summit of Mauna Kea who manages them? University of Hawaiʻi has any disaster occurred here? Yes - A number of the telescopes in the Mauna Kea Observatories sustained minor damage during the October 15, 2006 Kiholo Bay earthquake and aftershocks.
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2006 Kiholo Bay earthquake [SEP] Introduction
The 2006 Kīholo Bay earthquake occurred on October 15 at with a magnitude of 6.7 and a maximum Mercalli intensity of VIII ("Severe"). The shock was centered southwest of Puakō and north of Kailua-Kona, Hawaii, just offshore of the Kona Airport, at a depth of . It produced several aftershocks, including one that measured a magnitude of 6.1 seven minutes after the main shock. The Pacific Tsunami Warning Center measured a nondestructive tsunami of on the coast of the Big Island.