Dhaka, Aug 21 (UNB)- In the same decade when gravitational waves and a neutron star merger have been observed, astronomers have now observed what they believe to be the first detection of a black hole swallowing a neutron star, reports CNN.
Last Wednesday, gravitational wave detectors in Italy and the US, called LIGO and Virgo, detected telltale ripples in space and time, traced to an event that happened 8,550 million trillion kilometers away from Earth.
Astronomers are analyzing the data from the detection to confirm the size of the two objects that came together to form such cataclysmic ripples, but the event is likely a black hole eating a neutron star.
"About 900 million years ago, this black hole ate a very dense star, known as a neutron star, like Pac-man -- possibly snuffing out the star instantly," said Susan Scott, leader of the General Relativity Theory and Data Analysis Group at Australian National University and chief investigator with the ARC Centre of Excellence for Gravitational Wave Discovery. "The ANU SkyMapper Telescope responded to the detection alert and scanned the entire likely region of space where the event occurred, but we've not found any visual confirmation."
Essentially, black holes and neutron stars are the leftovers after stars die.
Neutron stars are the smallest in the universe, the remnants of supernovae. Their diameters are comparable to the size of a city like Chicago or Atlanta, but they are incredibly dense, with masses bigger than that of our sun.
When massive stars collapse at the end of their lives, they form an area of accelerating gravity so strong that nothing, including light, can escape it.
Like the other groundbreaking detections this decade, this new detection could provide more crucial evidence for previously unseen events that occur in space.
"We have always thought that there should be binary systems of a black hole and a neutron star circling each other out in space, so if this event is confirmed, it would be the first evidence that such systems do actually exist, and that some of them are spiraling closer and closer and eventually smashing together," Scott said.
If the neutron star is not much smaller in mass than the black hole, the astronomers would expect more orbits to bring them closer together. This would shred the neutron star, creating electromagnetic signals that can be detected, Scott said. The signal would tell the astronomers about the properties of the star, hinting at their mysterious composition.
But if the masses of the two objects differ, the neutron star would likely be swallowed whole and not emit radiation. Because there hasn't been a signal in the area where the event occurred, the researchers believe this is the scenario that occurred.
Astronomers want to learn the masses of the two objects. An object greater than five times the mass of the sun is considered a black hole. If it's less than three times the mass of the sun, it's a neutron star.
One potential small possibility is that the smaller object could be a very light black hole, Scott said, which would still be an exciting consolation prize.
"We are not aware of any black holes in the universe with masses less than about five solar masses," Scott said. "This would raise many new questions such as, 'how does such a light black hole form?'"
If the detection of the black hole swallowing the neutron star is confirmed, that would complete the detectors' trifecta this decade, including gravitational waves and neutron star collisions.
Gravitational waves are ripples in space and time. Neutron star collisions release gravitational waves, light and heavy elements like gold.
Earlier this year after the gravitational wave detectors were turned on in April, scientists believe they may have detected the never-before-seen collision of a neutron star and a black hole, a collision between two neutron stars and three potential black hole mergers. The detectors' observations are being regarded as candidates until further data can confirm them.
If this trifecta is complete, the researchers want to detect more systems, including black holes and neutron stars merging.
"We can better estimate the population size of these systems in the universe and also better understand how these systems 'get together' in the first place," Scott said. "On the extended wish list we would soon hope to have a supernova which goes off somewhere close so that we can capture the expected gravitational waves from this type of event and better model the supernova process."
The detection teams are also working on a way to detect the result of two neutron stars that briefly create a bigger neutron star when they collide. It's possible that this bigger neutron star would be short-lived, but any detection from it could inform the astronomers about the collision process for neutron stars and their structure.
Shenzhen, Aug 20 (AP/UNB) — The founder of Chinese tech giant Huawei said Tuesday he expects no relief from U.S. export curbs because of the political climate in Washington but expressed confidence the company will thrive because it is developing its own technology.
Ren Zhengfei also said he doesn't want relief from U.S. sanctions if it requires China to make concessions in a tariff war, even if that means his daughter, who is under house arrest in Canada on U.S. criminal charges, faces a longer legal struggle.
In an interview with The Associated Press at Huawei's sprawling, leafy headquarters campus in the southern city of Shenzhen, the 74-year-old Ren said Huawei expects U.S. curbs on most technology sales to go ahead despite Monday's announcement of a second 90-day delay. He said no one in Washington would risk standing up for the company.
The biggest impact will be on American vendors that sell chips and other components to Huawei, the biggest maker of network gear for phone companies, he said.
Washington has placed Huawei on an "entity list" of foreign companies that require official permission to buy American technology.
"Whether the 'entity list' is extended or not, that will not have a substantial impact on Huawei's business," said Ren. "We can do well without relying on American companies."
Huawei Technologies Ltd., China's first global tech brand, is at the center of a battle over trade and technology that threatens to tip the global economy into recession. American officials accuse the company, also the No. 2 global smartphone brand, of stealing technology and facilitating Chinese spying. Huawei denies those accusations.
Huawei's chief financial officer, who is also Ren's daughter, is fighting extradition from Canada to face U.S. charges related to possible violations of trade sanctions on Iran. Beijing arrested two Canadians in a possible attempt to force her release.
Ren looked relaxed and confident throughout the two-hour interview at a palatial new building in neoclassical European style where Huawei entertains customers. The atmosphere was a striking contrast from a June 17 news conference at which Ren compared the company to a "badly damaged airplane" and warned U.S. sanctions would cut Huawei's projected smartphone sales by $30 billion over the next two years.
President Donald Trump has suggested controls on Huawei might be lifted if Beijing agrees to a deal on trade and technology disputes that led to U.S. tariff hikes on Chinese imports.
Ren rejected that. He said Huawei couldn't ask for favors that might hurt the interests of China's poor majority.
"I couldn't take it if those poor people sacrificed their own interests for the benefit of Huawei," said Ren. "Maybe my daughter will suffer more. But I would rather do that instead having the poorer people in China sacrifice for Huawei's survival and development."
The May announcement of export curbs prompted warnings that sales of Huawei smartphones and other products that use U.S. chips and other technology could be devastated. The curbs also mean a loss of billions of dollars in potential annual sales for American vendors.
Even before the announcement, Huawei was working on developing its own chips, software and other technology that might reduce reliance on American vendors. The company spent $15 billion last year on research and development, more than Apple Inc. or Microsoft Corp.
Huawei reported sales in the six months through June rose 23.2% over a year earlier. Its chairman, Liang Hua, said in July that Huawei was reviewing its core products to make sure they all could be delivered to customers without American components.
"At a strategic level, the U.S. entity list is helpful to Huawei," said Ren. He said the company has responded by eliminating "marginal, unimportant businesses or products" and focusing resources on "major products."
"The whole company can focus more on our most competitive products," he said.
This month, Huawei unveiled its own smartphone operating system it said can replace the popular Android system from Alphabet Inc.'s Google. Huawei's phones still use Android but Google is blocked from supporting maps, music and other services.
Earlier this year, Huawei released its own chip for next-generation smartphones and the first phone based on that chip.
Ren rarely appeared in public or talked to reporters before his daughter's December arrest. Since then, however, he has given a flurry of interviews to foreign reporters in an effort to repair the company's reputation.
"I think it's working," he said.
Asked about ongoing pro-democracy protests in Hong Kong, which borders Shenzhen, Ren said the violence was "not good for society and the people" but doesn't affect Huawei.
"There is no impact at all on Huawei's business," he said. "We are still focused on our own production. We still focus on fixing the holes in our bullet-riddled airplane."
Ren, who has called himself a fan of the United States and publicly praised Trump as a leader, said Huawei wants to retain technology collaboration with Google, Microsoft and other American developers.
Ren said a strong market position for Huawei will help U.S. companies because Huawei's products use American technology.
If Huawei is blocked from using Android and is forced to develop alternative systems, "it wouldn't be in the best interests of the United States," Ren said.
He said even if Huawei develops its own alternatives, it is willing to buy American components to support industry development.
"We hope we can and we will continue to be able to buy American components," he said. "Even though we may have the ability to turn out our own components or products, we would choose to reduce our own capacity so as to use more American components in order to contribute together to share the prosperity of society."
Ren said Huawei is planning as if the U.S. export restrictions will remain in place.
"It isn't possible that someone in the United States will step up to revoke the entity list designation," he said. "Right now, attacking Huawei in the United States is politically correct, while helping Huawei even once would put them under significant pressure. So to us, the entity list will be there for quite some time."
Aboard A Nasa Research Plane Over Greenland, Aug 16 (AP/UNB) — The fields of rippling ice 500 feet below the NASA plane give way to the blue-green of water dotted with irregular chunks of bleached-white ice, some the size of battleships, some as tall as 15-story buildings.
Like nearly every other glacier on Greenland, the massive Kangerlussuaq is melting. In fact, the giant frozen island has seen one of its biggest melts on record this year. NASA scientist Josh Willis is now closely studying the phenomenon in hopes of figuring out precisely how global warming is eating away at Greenland's ice.
Specifically, he wants to know whether the melting is being caused more by warm air or warm seawater. The answer could be crucial to Earth's future.
Water brings more heat to something frozen faster than air does, as anyone who has ever defrosted a steak under the faucet knows.
If Willis' theory that much of the damage is from the water turns out to be correct, he said, "there's a lot higher potential for Greenland to melt more quickly than we thought." And that means seas rising faster and coastal communities being inundated more.
Greenland contains enough ice to make world sea levels rise by 20 feet if it were all to melt. In a single day this month, it lost a record 13.7 billion tons (12.5 billion metric tons) by one estimate.
"It's a little scary," Willis said as looked down on an area filled with more water than ice. "We're definitely watching the ice sheet disappear in front of us."
Climate change is eating away at Greenland's glaciers in two ways. The most obvious way is from the warm air above, which has been brutal this summer, with a European heat wave in July working like a hair dryer on the ice. The other way is from warm, salty water, some of it from North America's Gulf Stream, nibbling at coastal glaciers from below.
When University of Georgia ice scientist Tom Mote, who isn't part of this project, started studying Greenland's glaciers in the early 1990s, researchers really didn't think the water was a big factor.
Willis' project — called Oceans Melting Greenland, or OMG — is showing that it is. Now the question is how much and how fast.
What Willis is measuring is the water 660 feet (200 meters) or more below the surface, which is warmer and saltier than the stuff that touches the air. It's this deep water that does the major damage.
To measure this, NASA is spending five years crisscrossing the island in a tricked-out 77-year-old DC-3 built for World War II. Willis, project manager Ian McCubbin and mechanic Rich Gill drop long, cylindrical probes through a special tube in the floor of the plane, watching as the sensors parachute down and then dive into the chilly water.
McCubbin then waits for a tone on his computer that tells him the probe is underwater and measuring temperature and salinity. When all of the flight's five probes start signaling — with a sound McCubbin likens to "a fax machine or an AOL modem" — he and Willis high-five.
Meanwhile, pilots Andy Ferguson and Don Watrous bank the plane toward the blue-green spots, looking for the next target and pointing out stunning giant icebergs and signs of glacial retreat over the radio.
As the data is radioed back from one $2,000 probe now deep in the water near Kangerlussuaq in eastern Greenland, it initially looks like the temperature hasn't changed much over the last year or two, which could be good news. But that's just one data point. Each year for the past four years, NASA has been looking at all of Greenland, and the numbers overall haven't been quite as comforting.
If the water is playing a much bigger role than scientists thought, it could mean seas will be rising faster and higher than expected. That's because 90% of the heat energy from climate change goes into the oceans, Willis said. Warm water provides "a bigger bang for the buck" than air when it comes to melting ice, Willis said.
Just how crucial seawater is to melting was illustrated, somewhat paradoxically, by the Jakobshavn glacier, the fast-shrinking glacier on Greenland's more populated west coast. In recent years, it suddenly started to grow a bit, probably because of a cooling of waters as a result of a temporary shift in weather and water-current patterns, Willis said.
In general, oceans warm up much more slowly than the air, yet they stay warmer longer. The water weakens glaciers and causes icebergs to break loose. Those icebergs eventually melt, adding to the seas.
"Some of them are as big as a city," Willis said.
A 2019 study by Danish climate scientist Ruth Mottram looked at 28 glaciers in Greenland with long-term data. Nearly all are melting, with only one or two that could be considered somewhat stable.
"One glacier retreating looks like carelessness, but 28 retreating is the sign of something going on," Mottram told The Associated Press.
A 2017 study concluded that coastal glaciers and icecaps — what Willis is studying — reached a "tipping point" for ice loss in 1997 and since then have been rapidly deteriorating. A NASA satellite found that Greenland's ice sheet lost about 255 billion metric tons a year between 2003 and 2016, with the loss rate generally getting worse.
It will take centuries for all of Greenland's massive ice sheet to melt, but how fast is the key question. If warm water plays a bigger role than scientists suspect, by the year 2100, Greenland alone could cause 3 or 4 feet (more than 1 meter) of sea level rise, Willis said.
Other scientists, such as the University of Colorado's Ted Scambos, say Greenland's contribution to sea level rise by 2100 would probably be closer to 1 foot (30 centimeters).
That's a big spread.
"I tend toward the higher number, but I'm hoping for a lower number," said University of Maryland Baltimore County glaciologist Christopher Shuman, whose family owns property along the coast.
New Orleans, Aug 16 (AP/UNB) — NASA's top official says the rocket expected to power the next mission to the moon is about 90 percent complete.
NASA administrator Jim Bridenstine spoke during a visit Thursday to a facility in New Orleans where the core stage is being built.
The 212-foot-tall (65-meter-tall) core stage is made up of two liquid propellant tanks and four RS-25 engines.
In the months to come, the engine section will be attached to the rest of the core section. If all goes well, it will power the Artemis 1 test flight in 2020.
Plans call for the rocket to carry a crewless Orion capsule in a double loop around the moon during 25½ days in flight.
Future missions are expected to carry U.S. astronauts, including the first female astronaut to land on the moon.
San Francisco, Aug 15 (AP/UNB) — Hundreds of Google employees are calling on the company to pledge it won't work with U.S. Customs and Border Protection or Immigration and Customs Enforcement. It's the latest in a year full of political and social pushback from the tech giant's workforce.
A group of employees called Googlers for Human Rights posted a public petition urging the company not to bid on a cloud computing contract for CBP, the federal agency that oversees law enforcement for the country's borders. Bids for the contract were due Aug. 1. It is not clear if Google expressed interest. The company did not return a request for comment.
More than 700 Google employees had signed the petition by Tuesday afternoon. Citing a "system of abuse" and "malign neglect" by the agencies, the petition demands Google not provide any technical services to CBP, ICE or the Office of Refugee Resettlement (ORR), which provides services for refugees, until the agencies "stop engaging in human rights abuses."
"In working with CBP, ICE, or ORR, Google would be trading its integrity for a bit of profit, and joining a shameful lineage," the organizers wrote. They cited federal actions that have separated migrant children from parents and set up detention centers with poor conditions .
Google employees have led a growing trend in which some tech-company employees have taken public stances against their employers' policies. Thousands of Google employees walked out last fall to protest the company's handling of sexual misconduct claims. Employees also protested a Pentagon contract last year over work that used artificial intelligence technology to analyze drone footage.
The protests have chalked up some success. After the walkout , Google announced new sexual misconduct guidelines, although some employees say they don't go far enough. And the company did not renew the Pentagon contract after significant pushback.
Responding to some employee pressures has added fuel to claims from Republican pundits and lawmakers that the company is building its products to be biased against conservatives — an unfounded claim that has spawned multiple congressional hearings, although none that have produced evidence of bias.
Google was hit with criticism by President Donald Trump last week when the president tweeted he was "watching Google very closely" after a former employee claimed on Fox News — without evidence — that the company would try to influence the 2020 election against Trump.
Google has denied claims of political bias in its popular search service and other products.