LIGO detects gravitational waves again from colliding black holes

[ScienceRocks]

LIGO detects gravitational waves again from colliding black holes

For the second time, scientists have directly detected gravitational waves — ripples through the fabric of space-time, created by extreme, cataclysmic events in the distant universe. The team has determined that the incredibly faint ripple that eventually reached Earth was produced by two black holes colliding at half the speed of light,...

Understanding the nature of gravity is important in understanding how our universe works. Maybe with such a understand intelligent people could work to figure out how it all ties in. Maybe such understanding could lead to new physics that allow for the energy for "warp drive".

 

[waltky]

Japan's Astro-H satellite Data Adds to Understanding of 'Black Holes'...

New Data Adds to Understanding of 'Black Holes'
September 12, 2016 | WASHINGTON — Scientists continue to learn more about black holes in space, places where the pull of gravity is so strong that not even light can escape. Black holes occur after supergiant stars explode into brilliant but short-lived supernovas. All the matter dispersed by that titanic explosion collapses in a few weeks or months, and gravity crushes it all into a tiny space. Now, data from a Japanese satellite is helping decipher the secrets of these invisible singularities.

Black holes are invisible to the human eye. But telescopes with special tools can help find them by revealing how they affect nearby stars. In February, Japan’s space agency rocketed its Astro-H satellite into orbit to examine large-scale structures in the cosmos, like supermassive black holes that exist at the center of most galaxies. Unfortunately, after only about a month in space, the satellite fell apart. But before it went out of commission, it was able to gather vital data about the Perseus cluster, consisting of hundreds of galaxies 240 million light years from earth.

On board Astro-H was a unique X-ray spectrometer, which showed that superheated gas at the cluster's heart flows much more calmly than expected. "And that gives us a very precise measurement of how much energy is being pumped into this gas by supermassive black holes, and so it allows us to form a more complete picture of how galaxies evolve, how the stars and the gas that will eventually cool out like rain to form the stars, evolves over cosmic time,” explained Brian McNamara, an astrophysicist at the University of Waterloo in Canada.

Researchers are also closely looking at the hot plasma—a type of matter--and gases that surround the galaxies. "This is gas that has not cooled out and condensed out like rain in our atmosphere to form stars, planets, life, for example. So it's the potential for the future, and we're trying to understand what the future destiny of this galaxy and many other galaxies would be,” said McNamara.

Supermassive black holes may manipulate how galaxies form and evolve. “The energy released by these giant black holes is very tightly coupled to these atmospheres, which is the stuff out of which future stars will form,” said McNamara. And this means the invisible giant at their heart influences the rate at which a galaxy grows.

New Data Adds to Understanding of 'Black Holes'

 

[waltky]

Only 3,000 light years across...

Nearly naked black hole exposed by galactic close encounter
Nov. 2, 2016 - Researchers believe there may be other objects like B3 1715+425 out there waiting to be discovered.

Supermassive black holes are usually hidden away at the center of galaxies. But researchers at the National Radio Astronomy Observatory have discovered a black hole surrounded by relatively little galactic material. It's nearly naked, they say. According to a new paper published in the Astrophysical Journal, the black hole's home galaxy was stripped of material by a close encounter with a much larger galaxy. What's left of the black hole's galactic clothing stretches just 3,000 light-years across. The Milky Way, for comparison, is 100,000 light-years across. The unmasked black hole is surprising, not just for its limited galactic insulation, but because the black hole is fleeing the close encounter at a speed of 2,000 miles per second -- still intact.

When two galaxies collide, more often than not the resident black holes become locked in orbit, collide and merge. "We were looking for orbiting pairs of supermassive black holes, with one offset from the center of a galaxy, as telltale evidence of a previous galaxy merger," James Condon, a scientist at NRAO, said in a news release. "Instead, we found this black hole fleeing from the larger galaxy and leaving a trail of debris behind it. We've not seen anything like this before."

Astronomers named the black hole B3 1715+425. It's found near a cluster of galaxies called ZwCl 8193. The peculiarity of the bare black hole was identified and analyzed using data collected by the National Science Foundation's Very Long Baseline Array, a powerful radio telescope. "The data we get from the VLBA is very high quality," Condon said. "We get the positions of the supermassive black holes to extremely good precision."

Condon and his colleagues believe B3 1715+425 has a lonely future to look forward to. The black hole and what remains of its surrounding galaxy will soon stop making stars -- its galactic resources now limited. Eventually, it will disappear. For this reason, researchers believe there may be other objects like B3 1715+425 out there waiting to be discovered.

Nearly naked black hole exposed by galactic close encounter

See also:

Telescope Group Chooses Canary Islands as Alternative to Hawaii
November 01, 2016 - The team behind a project to build one of the world's largest telescopes said on Monday it has chosen Spain's Canary Islands in the Atlantic Ocean as a possible alternative to Hawaii.

The decision follows opposition from Native Hawaiians and environmentalists to plans for constructing the so-called Thirty Meter Telescope (TMT), which would cost $1.4 billion, at the Mauna Kea volcano on Hawaii's Big Island. Henry Yang, chair of the TMT International Observatory Board, said in a statement the board explored a number of alternative sites for the telescope. Ultimately, the board selected La Palma, the most westerly of the Canary Islands off the coast of Morocco, as the primary alternative to Hawaii, Yang said.

His statement did not say what made that particular site ideal for the project. The designation of the Canary Islands as an alternative comes nearly a year after the Hawaii Supreme Court blocked construction of the telescope on the Big Island. The court found state officials acted improperly when they issued a building permit without holding a process known as a contested case hearing where opponents could speak out.

The Gran Telescopio Canarias, one of the the world's largest telescopes, is viewed at the Observatorio del Roque de los Muchachos on the Canary Island of La Palma, Spain. The designation of the Canary Islands as an alternative site for the TMT comes nearly a year after the Hawaii Supreme Court blocked construction of the telescope on the Big Island.​

On Oct. 20, the Hawaii Department of Land and Natural Resources opened a new set of hearings on the project, with a retired judge overseeing those proceedings. The New York Times reported a decision on the latest application to build the telescope in Hawaii could be made next year. Yang said the Big Island continues to be the preferred choice of the team behind the telescope and the group will continue "intensive efforts to gain approval" for it in Hawaii.

The area around the summit of Mauna Kea, the volcano, already has 13 working telescopes, according to the website of the University of Hawaii's Institute for Astronomy. Astronomers consider the site ideal for observing outer space because of the dry atmosphere above the volcano and because of its distance from urban lights. Native Hawaiians who oppose the project have said the proposed site for the new telescope on the Big Island is considered a spiritual temple and also is a burial ground, adding the project could harm those sacred lands.

Telescope Group Chooses Canary Islands as Alternative to Hawaii