Saturday, December 1, 2012

PLANETARY TREMORS: 6.4 Magnitude Earthquake Strikes Southeast of Lakatoro, Vanuatu!

December 01, 2012 - VANUATU - A magnitude 6.4 earthquake has struck southeast of the Pacific island nation Vanuatu, just after 00:54:23 UTC local time and was located 17.012° south 167.626° east. 

According to the U.S. Geological Survey, the tremor had a depth of 34.1 kilometres (km) or 21.2 miles. The epicentre was determined to be at 101 km (63 miles) southeast of Lakatoro, Vanuatu; 108 km (67 miles) northwest of Port-Vila, Vanuatu; 170 km (106 miles) southeast of Luganville, Vanuatu; 433 km (269 miles) north of We, New Caledonia; and 581 km (361 miles) northeast of Dumbea, New Caledonia.

There is no immediate report of damage and the Pacific Tsunami Warning Center says there's no threat of a tsunami.


Seismotectonics of the Eastern Margin of the Australia Plate.
The eastern margin of the Australia plate is one of the most sesimically active areas of the world due to high rates of convergence between the Australia and Pacific plates. In the region of New Zealand, the 3000 km long Australia-Pacific plate boundary extends from south of Macquarie Island to the southern Kermadec Island chain. It includes an oceanic transform (the Macquarie Ridge), two oppositely verging subduction zones (Puysegur and Hikurangi), and a transpressive continental transform, the Alpine Fault through South Island, New Zealand.   Since 1900 there have been 15 M7.5+ earthquakes recorded near New Zealand. Nine of these, and the four largest, occurred along or near the Macquarie Ridge, including the 1989 M8.2 event on the ridge itself, and the 2004 M8.1 event 200 km to the west of the plate boundary, reflecting intraplate deformation. The largest recorded earthquake in New Zealand itself was the 1931 M7.8 Hawke's Bay earthquake, which killed 256 people. The last M7.5+ earthquake along the Alpine Fault was 170 years ago; studies of the faults' strain accumulation suggest that similar events are likely to occur again.

North of New Zealand, the Australia-Pacific boundary stretches east of Tonga and Fiji to 250 km south of Samoa. For 2,200 km the trench is approximately linear, and includes two segments where old (>120 Myr) Pacific oceanic lithosphere rapidly subducts westward (Kermadec and Tonga). At the northern end of the Tonga trench, the boundary curves sharply westward and changes along a 700 km-long segment from trench-normal subduction, to oblique subduction, to a left lateral transform-like structure.  Across the North Fiji Basin and to the west of the Vanuatu Islands, the Australia plate again subducts eastwards beneath the Pacific, at the North New Hebrides trench. At the southern end of this trench, east of the Loyalty Islands, the plate boundary curves east into an oceanic transform-like structure analogous to the one north of Tonga. - USGS.

PLANETARY TREMORS: Powerful 5.9 Magnitude Quake Shook Awake Residents of the Alaska Peninsula!

December 01, 2012 - ALASKA - Residents on Kodiak Island and the Kenai Peninsula in the state of Alaska were shaken awake at 11:00pm on Friday night as a 5.9 magnitude earthquake shook the region, but there are no immediate reports of any damages. The strong quake struck the Alaska Peninsula/ South Central region with a great deal of strength. It wasn’t like the mild succession of quakes that occurred Thursday.

The Alaska Earthquake Information Center says the quake was widely felt.

Jeff Antill wrote to us saying, “I felt and heard the 5.8 quake here in Anchorage. Our roof is heavy timbers and it makes alot of noise in even the smallest quakes. This one shook everything quite well.”

On the other hand, Chris Bryant says, “It wasn’t too bad. It felt like somebody was running on the deck outside. I only knew it was a quake because of the vibrations left over after the initial jolt.”

USGS map.
The Kodiak Police Department says there were no reports of damage or other problems early Saturday.

A quake of this size has the capacity to cause considerable damage under some circumstances.

The quick jolt occurred 69 miles north of Larsen Bay and 238 miles southwest of Anchorage. It was generated at a depth of 52.1 miles beneath the surface on the mainland across from Kodiak Island. The location of this earthquake was equidistant between the long quiet region of Devil’s Desk and Kaguyak Volcano. Devil’s Desk is a volcanic neck of a former stratovolcano now completely surrounded by Hook Glacier. Erosion has removed most of the stratovolcano. Wes Hildreth of USGS as well as others state that Devil’s Desk was active 292,000 years ago to the Holocene.

Kaguyak Volcano is another stratovolcano that had its last major eruption about 5,800 years before present, and has been largely quiet since that time with no recent eruptions or activity for at least the last 1,200 years. The National Oceanic and Atmospheric Administration’s West Coast and Alaska Tsunami Warning Center issued a statement advising that there was no tsunami danger from this quake.

The U.S. Geological survey has detected 20 earthquakes today, 214 earthquakes in the past 7 days, 830 earthquakes in the past month, and 17,479 earthquakes in the past year.

The Alaska quake was first reported as having a 5.6 magnitude energy level, however, seismologist changed it to a 5.9 in the last hour. - Guardian Express.

MONUMENTAL GALACTIC CHANGES: Colossal Super- Giant Black Hole Baffles Scientists - Equal to 17 Billion Suns, May Overturn Existing Models!

December 01, 2012 - SPACE - A group of astronomers led by Remco van den Bosch from the Max Planck Institute for Astronomy (MPIA) have discovered a black hole that could shake the foundations of current models of galaxy evolution. The Hubble image above shows the small, flattened disk galaxy NGC 1277, which contains one of the biggest central super-massive black holes ever found in its center. With the mass of 17 billion Suns, the black hole weighs in at an extraordinary 14% of the total galaxy mass --a mass much greater than current models predict — in particular in relation to the mass of its host galaxy. This could be the most massive black hole found to date. Astronomers would have expected a black hole of this size inside blob-like (“elliptical”) galaxies ten times larger. Instead, this black hole sits inside a fairly small disk galaxy.

Lenticular Galaxy NGC 1277.
If the additional candidates are confirmed, astronomers will need to rethink fundamentally their models of galaxy evolution. In particular, they will need to look at the early universe: The galaxy hosting the new black hole appears to have formed more than 8 billion years ago, and does not appear to have changed much since then. Whatever created this giant black hole must have happened a long time ago. To the best of our astronomical knowledge, almost every galaxy should contain in its central region what is called a supermassive black hole: a black hole with a mass between that of hundreds of thousands and billions of Suns. The best-studied super-massive black hole sits in the center of our home galaxy, the Milky Way, with a mass of about four million Suns. NGC 1277 is embedded in the nearby Perseus galaxy cluster, at a distance of 250 million light-years from Earth. All the ellipticals and round yellow galaxies in the image below are galaxies located in this cluster. Compared to all the other galaxies around it, NGC 1277 is a relatively compact. (Credit: David W. Hogg, Michael Blanton, and the SDSS Collaboration).

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For the masses of galaxies and their central black holes, an intriguing trend has emerged: a direct relationship between the mass of a galaxy’s black hole and that of the galaxy’s stars.Typically, the black hole mass is a tiny fraction of the galaxy’s total mass. But now a search led by the Dutch astronomer Remco van den Bosch (MPIA) has discovered a massive black hole that could upset the accepted relationship between black hole mass and galaxy mass, which plays a key role in all current theories of galaxy evolution. With a mass 17 billion times that of the Sun, the newly discovered black hole in the center of the disk galaxy NGC 1277 might even be the biggest known black hole of all: the mass of the current record holder is estimated to lie between 6 and 37 billion solar masses. The big surprise is that the black hole mass for NGC 1277 amounts to 14% of the total galaxy mass, instead of usual values around 0.1%. Is this surprisingly massive black hole a freak accident? Preliminary analysis of additional data suggests otherwise — so far, the search has uncovered five additional galaxies that are comparatively small, yet, going by first estimates, seemed to harbor unusually large black holes too. More definite conclusions have to await detailed images of these galaxies. (NGC 1277 is a compact disk galaxy with one of the biggest black holes known to date. Its black hole weighs 17 billion times the mass of the Sun, which amounts to a remarkable 14% of this galaxy’s total mass. Most of the stars in the galaxy are strongly affected by the gravitational pull of this black hole. The black hole was found by van den Bosch and collaborators and published in Nature on 29 November 2012.

The following animation shows representative orbits of the galaxy’s stars in this, taken from the dynamical model that was used to measure the black hole mass. The green orbit shows the orbit of the stars in the disk. The red orbit shows the strong gravitational pull near the black hole. The blue orbit is strongly influenced by the (round) dark matter halo. One second in this animation represents 22 million years of simulated time, and the horizontal size of this image amounts to 41 million lightyears (36 arcsec).

WATCH: Super-Giant Black Hole discovered.


WATCH: Remco van den Bosch on the giant black hole in the galaxy NGC 1277.