Women who use certain types of hormones after menopause still have an increased risk of developing breast cancer nearly two decades after they stop taking the pills, long-term results from a big federal study suggest.

Although the risk is very small, doctors say a new generation of women entering menopause now may not be aware of landmark findings from 2002 that tied higher breast cancer rates to hormone pills combining estrogen and progestin.

"The message is probably not clear" that even short-term use may have lasting effects, said Dr. Rowan Chlebowski of Harbor-UCLA Medical Center in Torrance, California. He discussed the new results Friday at the San Antonio Breast Cancer Symposium.

The results are from the Women's Health Initiative, a federally funded study that tested pills that doctors long thought would help prevent heart disease, bone loss and other problems in women after menopause. More than 16,000 women ages 50 to 70 were given combination hormone or dummy pills for five to six years.

The main part of the study was stopped in 2002 when researchers surprisingly saw more heart problems and breast cancers among hormone users. Women were advised to stop treatment but doctors have continued to study them and have information on about two-thirds.

With roughly 19 years of followup, 572 breast cancers have occurred in women on hormones versus 431 among those on dummy pills. That worked out to a 29% greater risk of developing the disease for hormone takers.

Still, it was a difference of just 141 cases over many years, so women with severe hot flashes and other menopause symptoms may decide that the benefits of the pills outweigh their risks, doctors say. The advice remains to use the lowest possible dose for the shortest time.

Why might hormones raise breast risk?

"The hormones are stimulating the cells to grow" and it can take many years for a tumor to form and be detected, said Dr. C. Kent Osborne, a Baylor College of Medicine breast cancer expert.

Women are prescribed hormones in combination because taking estrogen alone raises the risk of uterine cancer. However, one-quarter of women over 50 no longer have a uterus and can take estrogen alone for menopause symptoms.

So the same study tested estrogen alone versus dummy pills in more than 10,000 such women, and the conclusion was opposite what was seen with combination hormones. Women on estrogen alone for seven years had a 23% lower risk of developing breast cancer up to 19 years later. There were 231 cases among them versus 289 in the placebo group.

These results contradict what some observational studies have found, though, and doctors do not recommend any hormone use to try to prevent disease because of the murky picture of risks and benefits.

The federal study only tested hormone pills; getting hormones through a patch or a vaginal ring may not carry the same risks or benefits.

The results are another reason that hormone users should follow guidelines to get regular mammograms to check for cancer, said Dr. Jennifer Litton, a breast specialist at MD Anderson Cancer Center in Houston.

"Continuing to screen appropriately remains important," she said.

The United States warned North Korea Wednesday that its "deeply counterproductive" ballistic missile tests risk closing the door on prospects for negotiating peace but said it is "prepared to be flexible" and take concrete, parallel steps with Pyongyang toward an agreement.

U.S. Ambassador Kelly Craft delivered the message at a Security Council meeting less than three weeks before North Korean leader Kim Jong Un's end-of-December deadline for the Trump administration to come up with new proposals to revive nuclear diplomacy

Negotiations faltered after the U.S. rejected North Korean demands for broad sanctions relief in exchange for a partial surrender of the North's nuclear capabilities at Kim's second summit with U.S. President Donald Trump last February. North Korea has carried out 13 ballistic missile launches since May to pressure Washington, and has hinted at lifting its moratorium on nuclear and long-range missile tests if the Trump administration fails to make substantial concessions before the new year.

Craft warned North Korea that "the United States and the Security Council have a goal, not a deadline" of working toward peace, healing the wounds of the Korean War, and achieving the denuclearization of the Korean peninsula, a vision that Kim and Trump agreed to at their first summit in Singapore in June 2018.

The United States wants to make "crystal clear" to North Korea "that its continued ballistic missile testing is deeply counterproductive" to Trump's and Kim's shared objectives, she said. "These actions also risk closing the door on this opportunity to find a better way for the future."

Craft cited North Korean threats to take a "new path" in the coming weeks and its hints of "a resumption of serious provocations," which she said would mean they could launch space vehicles using long-range ballistic missile technology or test intercontinental ballistic missiles "which are designed to attack the continental United States with nuclear weapons."

The United States trusts that North Korea "will turn away from further hostility and threats, and instead make a bold decision to engage with us," she said. "If events prove otherwise, we, this Security Council, must all be prepared to act accordingly."

The council met for the second time in a week on North Korea's increasing ballistic missile and nuclear-related activities, this time at the request of the United States, which effectively blocked a council discussion on the North's dismal human rights situation expected on Tuesday.

Stephen Biegun, the Trump administration's special representative for North Korea, briefed the 15 council members over a private lunch but left Craft to address the open council meeting.

North Korea didn't speak at the meeting but key ally China called on Washington and Pyongyang to work together to keep tensions from escalating, and to nurture the rapprochement they had made over the last two years.

"Seize the hard-earned opportunity," Chinese Ambassador Zhang Jun said, calling on the two sides "to prevent the dialogue process from derailing or backpedaling."

Zhang called the current situation "very complicated" and "fragile" saying "the top priority is to resume dialogue of the two parties directly concerned, and avoid any confrontational actions."

"It's good to hear that the U.S. is still willing to be engaged in dialogues," he said. "But meanwhile both parties should continue to walk towards each other and then to accommodate the concern from the other side and to build up confidence and trust."

He called for the council to lift sanctions that affect the livelihoods of innocent people, saying this may encourage North Korea "to go forward in the right direction, may create a more favorable condition for dialogue."

Russia's U.N. Ambassador Vassily Nebenzia said Moscow would also like to see a resumption of dialogue.

But he said North Korea, having delivered on a freeze of nuclear and long-range missile tests, can't be expected to "continue to do so indefinitely in the absence of any moves its way."

"Negotiation is a two-way street," Nebenzia said. "That should be understood."

The Russian ambassador said it is "high time" that the council consider adopting a statement or resolution to encourage negotiations on denuclearization, security guarantees, and promoting stability on the Korean peninsula.

Craft responded saying "any discussion of a new road map or Security Council resolution must bear in mind the reality that over the past year and a half" North Korea has continued to advance its prohibited programs "and repeatedly refused to engage in sustained diplomatic engagement."

Stressing U.S. flexibility, she said, "we recognize the need for a balanced agreement and parallel actions that address the concerns of all parties."

"But we need a committed negotiating partner to take the reciprocal actions required for progress," Craft said.

The United States holds the Security Council presidency this month, and some diplomats have been puzzled at its refusal to sign a letter that would have authorized the Security Council to hold a meeting on the human rights situation in North Korea — after it said it would.

Without U.S. support, diplomats said European and other countries that wanted the U.N.'s most powerful body to discuss human rights in North Korea were one vote short of the number they needed to go ahead with a meeting.

Asked about the human rights issue on her way into the meeting, Craft said: "Human rights is every day, for me."

The Security Council discussed the human rights situation in North Korea from 2014 through 2017, but skipped 2018.

The China National Space Administration Tuesday released the first batch of three-dimensional images based on the data from the recently launched Gaofen-7 Earth observation satellite.

The Gaofen-7, an important part of China's high-definition Earth observation project, is the country's first civil-use optical transmission three-dimensional surveying and mapping satellite that reaches the sub-meter definition.

The 22 images unveiled show the Beijing Capital International Airport, the new Beijing Daxing International Airport, as well as some regions in China's Anhui, Guangdong and Shandong provinces. Airplanes, vehicles, buildings and trees can be clearly seen in the images.

The satellite, launched from the Taiyuan Satellite Launch Center in north China's Shanxi Province on Nov. 3, is in orbit at an altitude of 506 km and has a design life of eight years. More than 14,000 images have been obtained by the satellite.

It will be mainly used for 1:10,000-scale 3D mapping. Only a few countries have acquired this level of satellite surveying and mapping, said Cao Haiyi, chief designer of the Gaofen-7 at the China Academy of Space Technology.

Its horizontal positioning accuracy of ground objects is within five meters, and the height measurement accuracy about 1.5 meters, said Cao.

"It's like a precise ruler for measuring the land. Before the launch of Gaofen-7, we could only precisely locate super-highways, but now Gaofen-7 can help us accurately locate rural roads," Cao said.

The main users of Gaofen-7 are from the Ministry of Natural Resources, the Ministry of Housing and Urban-Rural Development and the National Bureau of Statistics.

China has an urgent need for 1:10,000-scale surveying and mapping data, as the country undergoes rapid economic development, drastic changes in urban and rural structure, a sharp reduction in farmland and frequent natural disasters.

Gaofen-7 will help solve problems in monitoring geographical conditions, housing and urban-rural construction and national statistics, Cao said.

It might serve major national projects, planning and economic construction. For example, development of the Xiong'an New area, the selection of venue sites of the 2022 Beijing Winter Olympics and key projects along the Belt and Road all need high-precision surveying and mapping data for decision-making.

"In the past, surveying and mapping work was labor-intensive and lasted for months or even years. With the new satellite, these tasks can be completed in minutes," Cao said.

The positioning accuracy of vehicles and mobile phones is determined by navigation satellites, while map accuracy is realized by surveying and mapping satellites, she said. Gaofen-7 can greatly improve the accuracy of China's maps.

NASA administrator Jim Bridenstine and the media got an up-close look Monday at a huge, newly completed rocket for the program aimed at putting a man and woman on the moon as early as 2024.

Bridenstine was in New Orleans to see the first of the "core stage" rockets for NASA's Space Launch System at the Michoud Assembly Center, where it was built for NASA's Artemis program.

The rocket, 212 feet (65 meters) tall and more than 27 feet (8 meters) in diameter, is to be loaded on a barge by year's end for transport to the Stennis Space Center in neighboring coastal Mississippi.

There, Bridenstine said, it will undergo tests before being transported to Cape Canaveral, Florida. According to NASA, the first non-reusable rocket is to be launched for a test flight carrying a spacecraft without a crew, a mission known as Artemis I. A second would later send a crewed spacecraft into space. The third mission, Artemis III, would put a man and woman on the south pole of the moon, with an eye toward a continued presence that would lead eventually to a trip to Mars.

"We are making significant progress towards achieving that Artemis III mission and getting our first woman and next man to the south pole of the moon in 2024," Bridenstine said.

Among others attending the NASA event was Jasmin Moghbeli, who is set to graduate from the astronaut training program next year.

"Just seeing us go back to the moon and doing that in a sustainable way and using that as a stepping bed to move on further than we've ever been before, going to Mars, is super exciting," Moghbeli said. "And the fact that I'm in the astronaut office now and, you know, to think of the next people to go on the moon, I will know them. And it will be such an incredible thing for girls around the country and around the world to see a woman on the moon for the first time."

For years, Kim Cobb was the Indiana Jones of climate science. The Georgia Tech professor flew to the caves of Borneo to study ancient and current climate conditions. She jetted to a remote South Pacific island to see the effects of warming on coral.

Add to that flights to Paris, Rome, Vancouver and elsewhere. All told, in the last three years, she's flown 29 times to study, meet or talk about global warming.

Then Cobb thought about how much her personal actions were contributing to the climate crisis, so she created a spreadsheet. She found that those flights added more than 73,000 pounds of heat-trapping carbon to the air.

Now she is about to ground herself, and she is not alone. Some climate scientists and activists are limiting their flying, their consumption of meat and their overall carbon footprints to avoid adding to the global warming they study. Cobb will fly just once next year, to attend a massive international science meeting in Chile.

"People want to be part of the solution," she said. "Especially when they spent their whole lives with their noses stuck up against" data showing the problem.

The issue divides climate scientists and activists and plays out on social media. Texas Tech's Katharine Hayhoe, an atmospheric scientist who flies once a month, often to talk to climate doubters in the evangelical Christian movement, was blasted on Twitter because she keeps flying.

Hayhoe and other still-flying scientists note that aviation is only 3% of global carbon emissions.

Jonathan Foley, executive director of the climate solutions think-tank Project Drawdown, limits his airline trips but will not stop flying because, he says, he must meet with donors to keep his organization alive. He calls flight shaming "the climate movement eating its own."

Over the next couple of weeks, climate scientists and environmental advocates will fly across the globe. Some will be jetting to Madrid for United Nations climate negotiations. Others, including Cobb, will fly to San Francisco for a major earth sciences conference, her last for a while.

"I feel real torn about that," said Indiana University's Shahzeen Attari, who studies human behavior and climate change. She calls Cobb an important climate communicator. "I don't want to clip her wings."

But Cobb and Hayhoe are judged by their audiences on how much energy they use themselves, Attari said.

Attari's research shows that audiences are turned off by scientists who use lots of energy at home. Listeners are more likely to respond to experts who use less electricity.

"It's like having an overweight doctor giving you dieting advice," Attari said. She found that scientists who fly to give talks bother people less.

In science, flying is "deeply embedded in how we do academic work," said Steven Allen, a management researcher at the University of Sheffield, who recently organized a symposium aimed at reducing flying in academia. He said the conference went well, with 60 people participating remotely from 12 countries.

Pennsylvania State University's Michael Mann, who flies but less than he used to, said moderation is key.

"I don't tell people they need to become childless, off-the-grid hermits. And I'm not one myself," Mann said in an email. "I do tell people that individual action is PART of the solution, and that there are many things we can do in our everyday lives that save us money, make us healthier, make us feel better about ourselves AND decrease our environmental footprint. Why wouldn't we do those things?"

Mann said he gets his electricity from renewables, drives a hybrid vehicle, doesn't eat meat and has one child.

When Hayhoe flies, she makes sure to bundle in several lectures and visits into one flight, including 30 talks in Alaska in one five-day trip. She said more people come out to see a lecture than if it were given remotely, and she also learns from talking to the people at lectures.

"They need a catalyst to get to the next step and me coming could be that catalyst," Hayhoe said.

Marshall Shepherd of the University of Georgia will receive a climate communications award at the American Geophysical Union conference Wednesday in San Francisco. But he won't pick it up in person, saving 1.2 tons of carbon by not flying. He said he doesn't judge those who fly but wrote about his decision to stay grounded in hopes that people "think about choices and all of the nuances involved in these decisions."

Former Vice President Al Gore, who has long been criticized by those who reject climate science for his personal energy use, said he has installed 1,000 solar panels at his farm, eats a vegan diet and drives an electric vehicle.

"As important as it to change lightbulbs," he said in an email, "it is far more important to change the policies and laws in the nation and places where we live."

Teen activist Greta Thunberg drew attention when she took a zero-carbon sailboat across the Atlantic instead of flying.

"I'm not telling anyone else what to do or what not to do," Thunberg told The Associated Press before her return boat trip. "I want to put focus on the fact that you basically can't live sustainable today. It's practically impossible."

Cobb is trying. In 2017, she started biking to work instead of driving. She's installed solar panels, dries clothes on a line, composts and gave up meat. All these made her feel better, physically and mentally, and gave her more hope that people can do enough to curb the worst of climate change.

But when she did the math, she found "all of this stuff is very small compared to flying."

Cobb began turning down flights and offering to talk remotely. This year she passed on 11 flights, including Paris, Beijing and Sydney.

"There hasn't been a single step I have taken that has not brought me a deeper appreciation for what we're up against and what's possible," Cobb said. "This gave me a profound appreciation for how individual action connects to collective action."

But there's a cost.

Cobb was invited to be the plenary speaker wrapping up a major ocean sciences conference next year in San Diego. It's a plum role. Cobb asked organizers if she could do it remotely. They said no. She promised to do many roles for the conference from Atlanta. Conference organizers withdrew the offer.

Brooks Hanson, executive vice president of the American Geophysical Union, which runs the conference, said in an email that the group supports remote presentations whenever possible. But the wrap-up speaker position "requires in-person interactions with attendees to get the vibe of the meeting and discussions," Hanson said.

Foley said that shows the problem: "Climate scientists and activists should walk the walk. But we can only walk so far. Then you bump into other things."