PBS News Hour - Science

Cities across the U.S. broke thousands of heat records this summer, but in many of them, some areas were hotter than others. These areas are known as urban heat islands, which can mean higher energy bills and unsafe conditions for residents. Blair Waltman-Alexin of Austin PBS, in partnership with Austin Vida, reports. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

You may have heard about a NASA probe that successfully brought some samples from a deep-space asteroid back to Earth. It took four billion miles to get them, but researchers believe it will be worth it. You also may be wondering just why scientists want these samples from what's essentially a huge rock flying through space. Science correspondent Miles O'Brien explains. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

In our news wrap Sunday, House negotiations to avoid a government shutdown enter their final week, France is ending its military presence in Niger, talks continued in the auto workers and Hollywood strikes, NASA retrieved its first asteroid samples from space, Ethiopian Tigist Assefa broke the women's world record at the Berlin Marathon, and Megan Rapinoe is playing her final game with the USWNT. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

Astronomers around the world are calling for international agreements to limit the spread of satellite constellations in space, with warnings that light pollution at night from the satellites damages vital scientific work. In Britain, the government is also being urged to impose new planning regulations to reduce light pollution to stop the loss of the nation's dark skies. Malcolm Brabant reports. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

Abandoned fishing gear, often called "ghost gear," is breaking down in our oceans and adding to the problems brought by plastics and microplastics. But there was a recent effort to get the United Nations to enforce tougher regulations, and a coalition announced new funding to remove some debris in the Gulf of Maine. Science correspondent Miles O'Brien reports. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

Next Saturday, the autumn equinox will mark the beginning of fall in the Northern Hemisphere. For some, though, the real start of fall is when the leaves change color. But scientists say climate change is affecting both the timing and intensity of fall foliage. John Yang speaks with Bill Keeton, a professor of forest ecology at the University of Vermont, to learn more. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

Africa is the continent most vulnerable to climate change, despite being responsible for just 2 to 3 percent of global carbon emissions and receiving only 3 percent of funding committed to climate mitigation and adaptation. Caroline Kimeu, The Guardian's East Africa global development correspondent, joins Ali Rogin to discuss Africa's first climate summit held this week in Kenya and its outcomes. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

Invasive species harm ecosystems around the world and cost the global economy $423 billion a year, according to a new report backed by the UN. A number of researchers believe that estimate may be just the tip of the iceberg. William Brangham speaks with one of the study's authors, Laura Meyerson of the University of Rhode Island, about the ways invasive species affect us. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

There has been an alarming number of near-miss collisions between airplanes according to an investigation by The New York Times. In a review of FAA reports and a NASA database, the Times found there were at least 46 close calls involving commercial flights in July and runway incursions are 25 percent higher than a decade ago. Geoff Bennett discussed more with aviation correspondent Miles O'Brien. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

While the world is focusing on the radioactive water released from the Fukushima nuclear plant in Japan, the country is grappling with other big questions about its use of nuclear energy. Japan dramatically changed its attitudes after Fukushima melted down in 2011. But since then, it's faced its share of problems with other energy sources and prices. Science correspondent Miles O'Brien reports. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders