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On Soccer: France, a World Cup Champion That Stood Above It All in Russia

NY Times - Sun, 2018-07-15 17:59
France always felt out of place in Russia, winning with an air of cultivated detachment, as though it were competing in a completely different tournament.

Ancient collision with ‘Sausage’ galaxy shaped the Milky Way

Futurity.org - Sun, 2018-07-15 17:45

Researchers have discovered an ancient and dramatic head-on collision between the Milky Way and a smaller object, dubbed the “Sausage” galaxy.

The cosmic crash was a defining event in the early history of the Milky Way and reshaped the structure of our galaxy, fashioning both its inner bulge and its outer halo, astronomers report in a series of new papers.

The astronomers propose that around 8 billion to 10 billion years ago, an unknown dwarf galaxy smashed into our own Milky Way. The dwarf did not survive the impact: It quickly fell apart, and the wreckage is now all around us.

“The collision ripped the dwarf to shreds, leaving its stars moving in very radial orbits” that are long and narrow like needles, says Vasily Belokurov of the University of Cambridge and the Center for Computational Astrophysics at the Flatiron Institute in New York City. The stars’ paths take them “very close to the center of our galaxy. This is a telltale sign that the dwarf galaxy came in on a really eccentric orbit and its fate was sealed.”

The three new papers in the Monthly Notices of the Royal Astronomical Society, in the Astrophysical Journal Letters, and on arXiv.org outline the salient features of this extraordinary event.

The researchers used data from the European Space Agency’s Gaia satellite. This spacecraft has been mapping the stellar content of our galaxy, recording the journeys of stars as they travel through the Milky Way. Thanks to Gaia, astronomers now know the positions and trajectories of our celestial neighbors with unprecedented accuracy.

The paths of the stars from the galactic merger earned them the moniker “the Gaia Sausage,” explains Wyn Evans of Cambridge. “We plotted the velocities of the stars, and the sausage shape just jumped out at us. As the smaller galaxy broke up, its stars were thrown onto very radial orbits. These Sausage stars are what’s left of the last major merger of the Milky Way.”

When looking at the distribution of star velocities in the Milky Way, the stars of the Sausage galaxy form a characteristic sausage-like shape. This unique shape is caused by the strong radial motions of the stars. As the sun lies in the center of this enormous cloud of stars, the distribution does not include the slowed-down stars currently making a U-turn back toward the galaxy’s center.

Sergey Koposov, a member of Carnegie Mellon University’s McWilliams Center for Cosmology, studied the kinematics of the Sausage stars and globular clusters in detail.

The Milky Way continues to collide with other galaxies, such as the puny Sagittarius dwarf galaxy. However, the Sausage galaxy was much more massive. Its total mass in gas, stars, and dark matter was more than 10 billion times the mass of our sun.

Is the Milky Way actually kind of weird?

When the Sausage crashed into the young Milky Way, its piercing trajectory caused a lot of mayhem. The Milky Way’s disk was probably puffed up or even fractured following the impact and would have needed to regrow. And Sausage debris was scattered all around the inner parts of the Milky Way, creating the “bulge” at the galaxy’s center and the surrounding “stellar halo.”

Numerical simulations of the galactic mashup can reproduce these features, says Denis Erkal of the University of Surrey. In simulations run by Erkal and colleagues, stars from the Sausage galaxy enter stretched-out orbits. The orbits are further elongated by the growing Milky Way disk, which swells and becomes thicker following the collision.

Evidence of this galactic remodeling is seen in the paths of stars inherited from the dwarf galaxy, says Alis Deason of Durham University. “The Sausage stars are all turning around at about the same distance from the center of the galaxy.” These U-turns cause the density in the Milky Way’s stellar halo to decrease dramatically where the stars flip directions.

This discovery was especially pleasing for Deason, who predicted this orbital pileup almost five years ago. The new work explains how the stars fell into such narrow orbits in the first place.

The Milky Way ate 11 other galaxies

The new research also identified at least eight large, spherical clumps of stars called globular clusters that were brought into the Milky Way by the Sausage galaxy. Small galaxies generally do not have globular clusters of their own, so the Sausage galaxy must have been big enough to host a collection of clusters.

“While there have been many dwarf satellites falling onto the Milky Way over its life, this was the largest of them all,” Koposov says.

Source: Carnegie Mellon University

The post Ancient collision with ‘Sausage’ galaxy shaped the Milky Way appeared first on Futurity.

Georgia Governor Candidate Caught Saying He’s in Race to Be the ‘Craziest’

NY Times - Sun, 2018-07-15 17:41
His opponent has recorded ads with a chain saw, shotgun and “big truck” that he says he’ll use to round up “illegal immigrants.” It seems to be working.

Plans Unveiled for Memorial at Site of Charleston Church Massacre

NY Times - Sun, 2018-07-15 17:41
Emanuel African Methodist Episcopal Church hopes to erect a lasting tribute to both victims and survivors of the 2015 hate crime, and to the resilience of a 200-year-old congregation.

Cambridge Dispatch: Parks Give Cambridge a Rural Vibe. ‘But Cows Do It Better.’

NY Times - Sun, 2018-07-15 17:36
The English university town, population 130,000, is also home to about 120 cattle. The urban herds have become another emblem of the city’s distinction.

These Arctic mammals are most at risk from ships

Futurity.org - Sun, 2018-07-15 17:18

As Arctic seas become increasingly ice-free, seasonal ship traffic from tourism and freight is expected to rise. A new study shows which animals will be the most vulnerable to the change.

In August 2016, the first large cruise ship traveled through the Northwest Passage, the northern waterway linking the Atlantic and Pacific oceans. The following year, the first ship without an icebreaker plied the Northern Sea Route, a path along Russia’s Arctic coast that was, until recently, impassable by unescorted commercial vessels.

“We know from more temperate regions that vessels and whales don’t always mix well, and yet vessels are poised to expand into this sensitive region,” says lead author Donna Hauser, who did the research as a postdoctoral researcher at the University of Washington and is now a research assistant professor at the University of Alaska Fairbanks.

“Even going right over the North Pole may be passable within a matter of decades. It raises questions of how to allow economic development while also protecting Arctic marine species.”

Narwhals and others

The study looked at 80 subpopulations of the seven marine mammals that live in the Arctic and identified their risks on or near major shipping routes in September, a month when the Arctic Ocean has the most open water.

Forty-two of these subpopulations would be exposed to vessel traffic, and the degree of exposure plus the particular characteristics of each species determine which are most sensitive.

As reported in the Proceedings of the National Academy of Sciences, the most vulnerable marine mammals are narwhals, or tusked whales. These animals migrate through parts of the Northwest Passage to and from their summertime habitats.

“Narwhals have all the traits that make them vulnerable to vessel disturbances—they stick to really specific areas, they’re pretty inflexible in where they spend the summer, they live in only about a quarter of the Arctic, and they’re smack dab in the middle of shipping routes,” says coauthor Kristin Laidre, a polar scientist at the University of Washington’s Applied Physics Laboratory’s Polar Science Center. “They also rely on sound, and are notoriously skittish and sensitive to any kind of disturbance.”

Beluga and bowhead whales are also vulnerable, researchers say. Walruses are vulnerable because some populations are relatively small and known to live along shipping routes, compared to generally large and widely distributed populations of ringed and bearded seals, which were shown to be less vulnerable.

The least vulnerable animals are polar bears, which are largely on land during September, and don’t rely on underwater sound for communication or navigation. Shipping in other seasons may have a greater impact.

‘Pinch point’ passages

The paper identified two “pinch points,” narrow passageways where ships and animals are most likely to intersect: The Bering Strait that separates the US and Russia, and Lancaster Sound in the northern Canadian territory of Nunavut. These regions have a risk of conflicts two to three times higher than on other parts of the shipping route.

“These obligatory pinch points are used by migratory species to get in and out of the Arctic, but they are also necessary passageways for vessels using these sea routes,” Hauser says. “Identifying the relative risks in Arctic regions and among marine mammals can be helpful when establishing strategies to deal with potential effects.”

Travel through the Arctic Ocean is already beginning, with the Russian route having the most potential for commercial ships. The Northern Sea Route had more than 200 ships from 2011 to 2016, all of which were large vessels. More than 100 vessels passed through the Northwest Passage during that time, with more than half being small, private vessels like personal yachts.

Here’s where narwhals like to hang out

In May, the International Maritime Organization established the first international guidelines for vessel traffic in the Arctic Ocean. The voluntary code was proposed by the US and Russia to identify safe routes through the Bering Strait.

The new study could help to create future guidelines, prioritize different measures to protect marine mammals and identify areas needing further study, the authors say.

“I think we can learn a lot from areas that have already been thinking about these kinds of conflicts between ships and marine mammal populations—for example the North Atlantic right whale, or fin and blue whales around California,” Laidre says.

Ship speed bothers killer whales more than size

“We could aim to develop some mitigation strategies in the Arctic that help ships avoid key habitats, adjust their timing taking into account the migration of animals, make efforts to minimize sound disturbance, or in general help ships detect and deviate from animals.”

NASA and the Collaborative Alaskan Arctic Studies Program funded the work. Harry Stern, a polar scientist at the UW Applied Physics Laboratory is a coauthor of the paper.

Source: University of Washington

The post These Arctic mammals are most at risk from ships appeared first on Futurity.

Review: Sacha Baron Cohen Is Back. Should We Care?

NY Times - Sun, 2018-07-15 17:12
“Who Is America?” on Showtime reprises the comedian’s gotcha techniques at a time when people don’t need to be tricked into saying embarrassing things.

How France Won Its Second World Cup Title

NY Times - Sun, 2018-07-15 17:06
Led by Kylian Mbappé and Paul Pogba, France brings home its second World Cup trophy, 20 years after winning its first.

Man Arrested in Scotland After Paraglider Unfurls Anti-Trump Banner

NY Times - Sun, 2018-07-15 17:03
Footage on the website of Greenpeace U.K. showed a paraglider with a banner that read “Trump Well Below Par” as President Trump arrived at his Turnberry golf resort.

Timeline: How Russian agents allegedly hacked the DNC and Clinton's campaign

Washington Post - Sun, 2018-07-15 17:00
Day by day, as the hacking unfolded.

Pussy Riot claims responsibility for interrupting final

CNN - Sun, 2018-07-15 16:57
Pussy Riot claimed responsibility for a group of protesters who took the field during the final World Cup match in Moscow on Sunday, indicating in a statement that the field invasion was staged to bring attention to political injustices in Russia.

A Look At The #MeToo Movement In The Shambhala Buddhist Community

NPR All Things Considered - Sun, 2018-07-15 16:48

NPR's Michel Martin speaks with Andrea Winn, who started investigating sexual abuse allegations within the Shambhala branch of Buddhism. Recently, that group's religious figurehead stepped down.

'Robin Williams: Come Inside My Mind' Explores Comic's Creative Life

NPR All Things Considered - Sun, 2018-07-15 16:44

A new documentary, Robin Williams: Come Inside My Mind, airs Monday on HBO. It aims to bring the viewer into his mind to see how he saw the world and the challenges he struggled with.

Director Gus Van Sant Discusses 'Don't Worry He Won't Get Far On Foot'

NPR All Things Considered - Sun, 2018-07-15 16:44

NPR's Michel Martin speaks with director Gus Van Sant about his new film, Don't Worry He Won't Get Far On Foot, which chronicles the fall and rise of cartoonist John Callahan.

How The Trump-Putin Summit Could Affect 2 Arms Control Treaties

NPR All Things Considered - Sun, 2018-07-15 16:44

The U.S. and Russia possess 92 percent of the earth's atomic arsenal. Both recently announced plans to build new nuclear weapons. How will the Trump-Putin summit affect two non-proliferation treaties?

France Defeats Croatia: A Recap Of The 2018 World Cup

NPR All Things Considered - Sun, 2018-07-15 16:44

NPR's Michel Martin recaps the World Cup final with Roger Bennett, host of the Men in Blazers and American Fiasco soccer podcasts.

MoviePass CEO Discusses Future Of Company And Business Model

NPR All Things Considered - Sun, 2018-07-15 16:44

NPR's Michel Martin speaks with MoviePass CEO Mitch Lowe about the future of the MoviePass subscription service, which is on the brink of bankruptcy.

6-Year-Old Girl Heard Crying On ProPublica Tape Has Been Reunited With Her Mother

NPR All Things Considered - Sun, 2018-07-15 16:44

NPR's Michel Martin speaks with ProPublica's Ginger Thompson, about the reunification of Cindy Madrid and her 6-year-old daughter, Jimena, who were separated at the border.

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