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washington — NASA’s rover Perseverance on Mars has made what could be its most astonishing discovery to date: possible signs of ancient life on the Red Planet.

The six-wheeled robotic explorer came across an intriguing, arrow-shaped rock dubbed “Cheyava Falls” that may harbor fossilized microbes from billions of years ago, when Mars was a watery world.

Perseverance drilled into the enigmatic rock to collect a core sample on July 21, as it traversed Neretva Vallis, an ancient river valley.

The samples carefully stowed beneath the rover’s belly are destined to eventually return to Earth, where they will undergo more comprehensive analysis.

“Cheyava Falls is the most puzzling, complex, and potentially important rock yet investigated by Perseverance,” project scientist Ken Farley of Caltech said Thursday.

Three compelling clues have scientists buzzing.

White calcium sulfate veins run the length of the rock, a telltale sign that water once flowed through it.

Between these veins is a reddish middle area, teeming with organic compounds, as detected by the rover’s SHERLOC (Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals) instrument.

Finally, tiny off-white splotches ringed with black, reminiscent of leopard spots, contain chemicals that suggest energy sources for ancient microbes, according to scans by the PIXL (Planetary Instrument for X-ray Lithochemistry) instrument.

“On Earth, these types of features in rocks are often associated with the fossilized record of microbes living in the subsurface,” said David Flannery, an astrobiologist and member of the Perseverance science team from the Queensland University of Technology in Australia.

The quest to confirm ancient Martian life is far from over, however.

The real test will come when Perseverance’s precious rock samples are returned to Earth as part of the Mars Sample Return Program, a collaboration between NASA and the European Space Agency slated for the 2030s.

While there are alternative explanations for these findings that do not involve microbes, there is a tantalizing chance that Perseverance’s core sample might contain actual fossilized microbes — potentially making history as the first proof of life beyond Earth.

“We have zapped that rock with lasers and X-rays and imaged it literally day and night from just about every angle imaginable,” said Farley.

“Scientifically, Perseverance has nothing more to give. To fully understand what really happened in that Martian river valley at Jezero Crater billions of years ago, we’d want to bring the Cheyava Falls sample back to Earth, so it can be studied with the powerful instruments available in laboratories,” he explained.
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washington — Thousands of policymakers, health care professionals and advocates gathered this week in Munich, Germany, to take stock of the global fight against HIV as they try to meet the 2030 deadline set by world leaders for eliminating AIDS as a public health threat.

Advocates hailed sub-Saharan Africa’s progress in the global HIV response, with tens of millions of people now on lifesaving drugs.

A new UNAIDS survey released during the conference reported that “approximately 30.7 million of the estimated 39.9 million people living with HIV globally were receiving antiretroviral therapy in 2023.”

The report called that result a “landmark public health achievement,” and health officials at the conference said it would not be possible without the “immense political will” of regional leaders and NGOs.

Anne Githuku-Shongwe, the UNAIDS regional director for eastern and southern Africa, told VOA from Johannesburg that recently there has been a “huge focus” on ensuring that anyone living with HIV in sub-Saharan Africa gets access to testing and treatment to ensure virus suppression, so the virus becomes untransmissible.

“The data is telling us that 84% of people living with HIV in our region have access to treatment. And 94% of those on treatment have been able to keep [the virus] suppressed so it is untransmissible,” she said.

However, Githuku-Shongwe pointed out that despite the progress that has been made, some countries in Africa are lagging behind in the battle against HIV/AIDS, partly because of civil wars, humanitarian setbacks and sheer negligence. She mentioned South Sudan, Angola, Madagascar, Mauritius, Seychelles and the Comoros as examples.

“[Countries] like Mauritius are barely at 50% of the treatment target,” she said, adding that another critical challenge being faced is the lack of attention to children living with the virus.

The report said children aged 0-14 years are still contracting HIV. An estimated 120,000 children got the virus in 2023, bringing the number of children living with HIV globally to 1.4 million, 86% of whom are in sub-Saharan Africa, according to the UNAIDS report.

Worries about donor funding

Githuku-Shongwe said there have been major investments from partners – particularly from PEPFAR, a U.S.-funded initiative to tackle the HIV/AIDS crisis, and the Global Fund to Fight AIDS, Tuberculosis and Malaria. She noted that in some countries, up to 99% of the HIV response is externally funded.

“But with time we are seeing that dwindling,” she said.

Nearly $19.8 billion was available in 2023 for HIV programs in low- and middle-income countries, almost $9.5 billion short of the amount needed by 2025, the report said.

Catherine Connor, vice president in charge of public policy and advocacy at the Elizabeth Glaser Pediatric AIDS Foundation, a Washington nonprofit, told VOA from Munich that the data on infections in children were “troubling” and pointed to a lackadaisical approach toward pediatric HIV.

“The report clearly shows that children are one out of every 10 new infections, which is really high,” she said. “But there’s also an outsized mortality issue around children. Children make up 3% of the HIV-infected population, but they represent 12% of deaths.”

Connor said there’s inequity in treatment, particularly for children living with HIV.

“Children can’t take themselves to clinics. They often don’t even know they’ve been exposed to HIV,” she said. “So they really rely on caregivers, the community around them, to ensure not just that they can be identified as being HIV-exposed or potentially HIV-positive, but also get the needed support to maintain their health, even if they are on treatment.”

Connor concluded that world leaders and policymakers should be made aware how significant it is to act on HIV prevention, because if the world fails to take steps to curtail the virus, then “we will not end AIDS.”

“It’s almost like having a dam holding back a river of water,” she said.

“HIV is preventable and treatable, but it is not curable. And so, if we let cracks in that dam get so bad, it’s going to break, and we are going to see a reemergence of the HIV/AIDS pandemic in ways we have never seen,” Connor said.
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United Nations — The U.N. Secretary-General warned Thursday that the Earth is becoming hotter and more dangerous for everyone, killing nearly a half-million people annually, and he blamed fossil fuels for driving global warming.

“Billions of people are facing an extreme heat epidemic — wilting under increasingly deadly heat waves, with temperatures topping 50 degrees Celsius around the world. That’s 122 degrees Fahrenheit. And halfway to boiling,” Antonio Guterres told reporters.

Sunday was the Earth’s hottest day on record, only to have the record broken the following day. Temperatures have been rising steadily, with scientists declaring the last 13 consecutive months all heat record-breakers. Urban areas are heating up at twice the global average.

Heat waves have killed scores of people this year in India and in Africa’s Sahel region. Last month, extreme heat killed 1,300 Muslim pilgrims in Saudi Arabia. This month, Europe, the United States and Asia have also seen exceptional heat.

He said that the World Health Organization and World Meteorological Organization estimate that improvements to heat health warning systems in 57 countries could save nearly 100,000 lives a year.

Fossil fuels

Guterres has repeatedly called on greenhouse gas emitters to meet the 2015 Paris Climate Accord’s target of limiting global temperature rise to 1.5 degrees Celsius — a goal that many worry is slipping away. He said that fossil fuel expansion and new coal plants are obstacles to meeting that target.

“I must call out the flood of fossil fuel expansion we are seeing in some of the world’s wealthiest countries,” he said. “In signing such a surge of new oil and gas licenses, they are signing away our future.”

He urged leaders to quickly and fairly phase out fossil fuels and end new coal projects.

“The G20 must shift fossil fuel subsidies to renewables and support vulnerable countries and communities,” he said of the world’s largest economies.

And he urged more climate adaptation and mitigation financing from the richest countries — which are the biggest emitters — to help the poorest, most vulnerable nations that have contributed the least to global warming.

Guterres said he is launching a global call to action focused on caring for the most vulnerable, including protecting workers who are exposed to extreme heat.

“A new report from the International Labor Organization — being released today — warns that over 70% of the global workforce — 2.4 billion people — are now at high risk of extreme heat,” he said.

In addition to the rights and health of individual workers, there are economic impacts of extreme heat too.

“Heat stress at work is projected to cost the global economy $2.4 trillion by 2030. Up from $280 billion in the mid-1990s,” Guterres said, adding measures need to be taken to “heat proof” critical sectors of the global economy, like farming and construction work.

The U.N. chief warned that extreme heat widens social inequality, undermines development, furthers food insecurity, and pushes people deeper into poverty.

“Leaders across the board must wake up and step up,” he said.
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