Day: November 9, 2017

Stellar Encore: Dying Star Keeps Coming Back Big Time

Death definitely becomes this star.

Astronomers reported Wednesday on a massive, distant star that exploded in 2014 — and also, apparently back in 1954. This is one supernova that refuses to bite the cosmic dust, confounding scientists who thought they knew how dying stars ticked.

The oft-erupting star is 500 million light-years away — one light-year is equal to 5.9 trillion miles (9.5 trillion kilometers) — in the direction of the Big Bear constellation. It was discovered in 2014 and, at the time, resembled your basic supernova that was getting fainter.

But a few months later, astronomers at the California-based Las Cumbres Observatory saw it getting brighter. They’ve seen it grow faint, then bright, then faint again five times. They’ve even found past evidence of an explosion 60 years earlier at the same spot.

Supernovas typically fade over 100 days. This one is still going strong after 1,000 days, although it’s gradually fading.

The finding was published Wednesday in the journal Nature.

“It’s very surprising and very exciting,” said astrophysicist Iair Arcavi of the University of California, Santa Barbara who led the study. “We thought we’ve seen everything there is to see in supernovae after seeing so many of them, but you always get surprised by the universe. This one just really blew away everything we thought we understood about them.”

The supernova — officially known as iPTF14hls — is believed to have once been a star up to 100 times more massive than our sun. It could well be the biggest stellar explosion ever observed, which might explain its death-defying peculiarity.

It could be multiple explosions occurring so frequently that they run into one another or perhaps a single explosion that repeatedly gets brighter and fainter, though scientists don’t know exactly how this happens.

One possibility is that this star was so massive, and its core so hot, that an explosion blew away the outer layers and left the center intact enough to repeat the entire process. But this pulsating star theory still doesn’t explain everything about this supernova, Arcavi said.

Harvard University’s astronomy chairman, Avi Loeb, who was not involved in the study, speculates a black hole or magnetar — a neutron star with a strong magnetic field — might be at the center of this never-before-seen behavior. Further monitoring may better explain what’s going on, he said.

Las Cumbres, a global network of robotic telescopes, continues to keep watch.

Scientists do not know whether this particular supernova is unique; it appears rare since no others have been detected.

“We could actually have missed plenty of them because it kind of masquerades as a normal supernova if you only look at it once,” Arcavi said.

Nothing lasts forever — not even this super supernova.

“Eventually, this star will go out at some point,” Arcavi said. “I mean, energy has to run out eventually.”

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US Commerce Secretary to Sell Stake in Firm With Russian Ties

Commerce Secretary Wilbur Ross plans to completely divest from a shipping company that counts a Russian gas producer with ties to the Kremlin among its major customers.

 

A commerce department spokesman says Ross plans to sell all his shares of Navigator Holdings. That company ships products from Sibur, a Russian gas producer whose owners include two Russian oligarchs close to President Vladimir Putin and a businessman believed to be Putin’s son-in-law.

 

Details of the Ross stake in Navigator were revealed among the Paradise Papers leak of documents about offshore entities.

 

Critics have said Ross should not hold the stock given his public office. He has said that he disclosed his stake in reports filed with the government earlier this year and has done nothing wrong.

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EU Pushes Cut in Car Emissions, Boost for Electric Vehicles

The European Commission said Wednesday it wants to cut emissions of carbon dioxide from cars by 30 percent by 2030 and boost the use of electric vehicles by making them cheaper and easier to charge.

 

The proposal stops short of imposing fixed quotas for emission-free vehicles and is more modest than goals already set out by some EU members. Still, European automakers said the commission’s targets were too drastic, and Germany’s foreign minister warned against the proposal.

 

Commission Vice President Maros Sefcovic insisted that the plan is the most “realistic” compromise between Europe’s ambitions to blaze trails on clean energy and the costs that the continent’s powerful car manufacturers will have to bear to overhaul workforces and production.

 

Current targets require automakers to achieve the average permitted emission for new models in the European Union of 95 grams of CO2 per kilometer for cars, or 147 grams for light commercial vehicles by 2021.

 

The new proposal foresees a further reduction of 15 percent by 2025 and 30 percent by 2030, compared to 2021 levels.

 

Car companies that fail to meet those targets face substantial fines of 95 euros ($110) per excess gram of carbon dioxide – per car. Automakers that manage to equip at least 30 percent of their new cars with electric or other low-emission engines by 2030 will be given credits toward their carbon tally.

 

The European Automobile Manufacturers’ Association, an industry body, criticized the 2025 target, saying “it does not leave enough time to make the necessary technical and design changes to vehicles, in particular to light commercial vehicles given their longer development and production cycles.”

 

The lobby group also said the targeted cut of 30 percent by 2030 was “overly challenging” and called for a 20 percent reduction instead, saying that was “achievable at a high, but acceptable, cost.”

 

“The current proposal is very aggressive when we consider the low and fragmented market penetration of alternatively-powered vehicles across Europe to date,” the group’s secretary general, Erik Jonnaert, said.

 

Germany’s foreign minister wrote to the commission last week to say the new rules shouldn’t “suffocate” the ability of automakers to innovate.

 

In a letter obtained by The Associated Press, Foreign Minister Sigmar Gabriel said all European countries benefit from the jobs the auto industry creates and warned that the time frame for emissions cuts “mustn’t be too restrictive.”

 

The letter caused friction within the German government, which is currently hosting a two-week United Nations meeting on implementing the 2015 Paris climate accord.

 

“The contents of this letter weren’t coordinated within the Cabinet,” a spokeswoman for Germany’s environment ministry, Friederike Langenbruch, told reporters in Berlin.

 

Germany is predicted to fall short of its own climate goals, in large part due to continued high emissions from coal-fired electricity plants and vehicle traffic.

 

The European executive’s plan also includes 800 million euros in funding for the expansion and standardization of electric charging stations Europe-wide.

 

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Emerging Nations Urge Wealthy Countries to Kick-start Climate Pact Before 2020

Emerging nations pressed developed countries Wednesday to step up cuts in greenhouse gas emissions by 2020 to kick-start the Paris climate agreement, saying the rich were wrongly focused on 2030 goals.

“We came here needing to hit the accelerator, not the brakes,” Brazil’s chief negotiator Antonio Marcondes told Reuters on the sidelines of the November 6-17 negotiations in Germany on limiting global warming.

In 2015, almost 200 governments agreed on the Paris accord to end the fossil fuel era by 2100 and remained united last year in declaring action “irreversible” after Donald Trump, who has called man-made climate change a hoax, won the U.S. presidential election.

But that unity is fraying.

Under the Paris Agreement, most governments set targets for cutting emissions by 2030, with little focus on shorter-term milestones.

Brazil and nations including India, China and Iran now want to fill the gap with more action by 2020 to cut greenhouse gas emissions, especially by the rich, which have burned the most fossil fuels since the Industrial Revolution.

“While action on [the] post-2020 period under the Paris Agreement has gained momentum, the discussions on pre-2020 actions have lagged behind,” India’s chief negotiator Ravi S. Prasad said this week.

Actions defended

Developed nations say they are acting. European Union officials pointed to proposals on Wednesday for tougher car emissions targets, including a credit system for carmakers to encourage the rollout of electric vehicles.

Nazhat Shameem Khan, chief negotiator for Fiji, which is presiding at the meeting, said: “Clearly, there is strong appetite for a constructive and focused discussion on pre-2020.

“I think it’s a generalized view … that there hasn’t been enough discussion” about what to do before 2020, she said.

Overall, she said, the talks, also working on a detailed rule book for the Paris Agreement, were advancing well and that the United States delegation was being “constructive and helpful.”

Trump said in June that he would pull the United States out of the Paris Agreement, a process that will take effect in 2020, and instead promote coal and oil.

A pullout will isolate the United States since Syria, the only other nation outside the pact, said Tuesday that it would join.

Under the Paris Agreement, the period to 2020 is a gap partly because backers of the 2015 pact assumed it might take years for parliaments to ratify it. The deal entered into force in record time last November.

Camilla Born, of the E3G think tank, said the Paris Agreement was now a victim of its own success. “It’s right now to shine the spotlight on more action by 2020,” she said.

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