The image shows Mars from orbit, with the white Arsia Mons Elongated Cloud stretching across the orange landscape from the volcano Arsia Mons. First recorded by NASA’s Viking Orbiter 2 in 1977, the feature has since been captured in greater detail by the European Space Agency’s Mars Express; the featured view dates to 2018. Its striking length and recurring appearance make it a puzzle for planetary scientists.
The cloud is made of water ice and appears only during Martian spring and summer, in the morning. It forms near Arsia Mons, then winds carry it downstream into a tail that can reach more than 1,500 kilometers. The familiar process of ice crystals forming around dust particles seems unlikely here: the high Martian atmosphere is very thin and contains little dust. One leading explanation is that dust is not needed for this cloud to form. Continued study of the phenomenon may clarify how clouds develop in unusual atmospheric conditions and help scientists build a fuller understanding of cloud formation on Earth.
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Regulators approved generic versions of lenacapavir, a long-acting HIV-prevention drug, for use in low-income countries. The approval could expand access to injections given twice a year to prevent HIV infection. (apnews.com)
About 12% of new cancer cases worldwide in 2024 - roughly 2.3 million - were linked to infections, according to WHO researchers. Five pathogens, including H. pylori, HPV and hepatitis B, caused most of these cases and are linked to cancers such as stomach, cervical and liver cancer. (theconversation.com)
A proposed Alzheimer’s definition counts people with disease-related brain changes even when they have no symptoms, potentially expanding the number diagnosed by hundreds of millions. Experts dispute the change and question whether new amyloid-targeting drugs meaningfully slow cognitive decline. (newyorker.com)
Vitamin K deficiency bleeding among U.S. infants rose nearly 350% as more parents declined the newborn shot, with cases roughly doubling from 2024 to 2025. Babies who missed the injection faced higher bleeding rates, including more than twice the risk of brain bleeds. (nytimes.com)
The National Weather Service has been ordered to resume twice-daily weather balloon launches nationwide. The restored observations will strengthen weather forecasting after the service reduced balloon data collection in March 2025. (cbsnews.com)
![How to Lie With Statistics (1954) [pdf]](https://hntoday.pixelshot.io/screenshots/20261105/a419b293013c4c01_tn.jpeg)
How to Lie With Statistics explains how numbers and charts can mislead when data is presented selectively or inaccurately. It teaches readers to spot common tricks, such as biased samples and deceptive graphs. (horace.org)
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