A skyquake is a phenomenon where a loud banging sound is reported to originate from the sky. The sound may cause noticeable vibration in the ceiling or across a particular room. Those who experience skyquakes typically do not have a clear explanation for what caused them and they are perceived as mysterious.
They have been heard in several locations around the world, including the banks of the river Ganges, Marwadi/Marawadi (मरवड़ी/मराड़ी) village in Himachal Pradesh, Hanswar, Uttar Pradesh, the East Coast and inland Finger Lakes of the United States, the city of Hudson, Wisconsin, the Magic Valley in south-central Idaho, the Municipality of Anchorage and Southcentral Alaska, Colombia, Southern Canada, as well as areas of the North Sea, Japan, Finland, Australia, Italy, Ireland, India, The Netherlands, Norway, Tierra del Fuego in Argentina, the United Kingdom, Mexico and Indonesia (particularly Jakarta and Java).
Names (according to area) are:
dentuman (lit: "clatter") or suara tembakan meriam (lit: "the sound of cannon fire").
"brontidi", "marina", "balza", "lagoni", "bomba", "rombo", "boato", "bonnito", "mugghio", "baturlio", "tromba", "rufa".[2] [3]
"uminari" (literally, "cries from the sea")
"Guns of the Seneca" around Seneca Lake and Cayuga Lake, Seneca guns in the Southeast US
In 1804, they were reportedly heard during the Lewis and Clark Expedition near Great Falls. Meriwether Lewis wrote “since our arrival at the falls we have repeatedly witnessed a noise which proceeds from a direction a little to the N. of West as loud and resembling precisely the discharge of a piece of ordinance of 6 pounds at the distance of three miles.” William Clark added in his notes, “…a rumbling like Cannon at a great distance is heard to the west of us; the Cause we Can’t account.”[5]
They have been reported from an Adriatic island in 1824; Western Australia, South Australia and Victoria in Australia; Belgium; frequently on calm summer days in the Bay of Fundy and Passamaquoddy Bay, New Brunswick, Canada; Lough Neagh in Northern Ireland; Scotland; Cedar Keys, Florida; Franklinville, New York in 1896; and northern Georgia in the United States.[6]
Their sound has been described as being like distant but inordinately loud thunder while no clouds are in the sky large enough to generate lightning. Those familiar with the sound of cannon fire say the sound is nearly identical. The booms occasionally cause shock waves that rattle plates. Early white settlers in North America were told by the native Haudenosaunee Iroquois that the booms were the sound of the Great Spirit continuing his work of shaping the earth.
The terms "mistpouffers" and "Seneca guns" both originate in Seneca Lake, NY, and refer to the rumble of artillery fire. James Fenimore Cooper, author of The Last of the Mohicans, wrote "The Lake Gun" in 1850, a short story describing the phenomenon heard at Seneca Lake, which seems to have popularized the terms.
Their origin has not been positively identified. They have been explained as: