John C. Martin, who became a billionaire by developing and marketing a daily single-dose pill that transformed H.I.V. into a manageable disease and who popularized another drug that cures hepatitis C, died on March 30 in Palo Alto, Calif. He was 69. His death, in a hospital, was confirmed by Gilead Sciences, based in Foster […]
So far, about 43 percent of Americans have received at least one dose of a Covid-19 vaccine, and 29 percent have received both doses of the two vaccines requiring double shots. The United States is averaging around 55,000 new cases a day, a roughly 20 percent drop from two weeks ago, according to a New […]
A lot has changed since early 2020, when countries around the world first realized the potential threat of a highly contagious, and still mysterious, flulike virus. In the early days of the coronavirus pandemic, no one knew for sure how the virus spread. People were scrubbing their groceries. Governments urged people to stay home, to […]
The moon’s surface is pockmarked with craters, the relics of violent impacts over cosmic time. A few of the largest are visible to the naked eye, and a backyard telescope reveals hundreds more. But turn astronomical observatories or even a space probe on our nearest celestial neighbor, and suddenly millions appear. Bettina Forget, an artist […]
“One of the major problems has been bulk and weight,” said Gary Bradski, chief technologist at OpenCV.ai, a developer of freely available machine vision software. “I mean how much weight can your nose hold?” Lightness is an advantage offered by Metalenz, which has demonstrated ultrathin lenses of two-dimensional silicon patterned with ultratiny transparent structures, each […]
Where does a candle go when it burns, anyway? Is it healthy to be breathing in melted candle particles? How concerned should I be? — Abigail B., Washington, D.C. When candles burn, most of their matter goes into the air. The light and heat from a candle comes from the wax burning. When you light […]
This week is the one-year anniversary of the At Home section, and what better way to celebrate than with a puzzle containing a hidden picture? Solve the clues and reveal the twist, with a mini shout-out to the section’s basket-weaving activity from August. Write the answers to the 16 clues in the blank spaces on […]
“Endeavour arriving.” With those words, the four members of the SpaceX Crew Dragon Endeavour began floating one by one into the International Space Station on Saturday morning, about 24 hours after their capsule lifted off from the Kennedy Space Center in Florida. The Endeavour docked onto the space station shortly after 5 a.m., according to […]
As the astronauts were getting ready for sleep, there were a few minutes of concern: Mission controllers at SpaceX headquarters in California warned the crew that a piece of space debris was going to whiz past the capsule at about 1:43 p.m. Eastern time. The astronauts were told to put on their spacesuits, get back […]
Without hospitals or medical specialists in space, NASA and other space agencies have always been concerned about astronauts falling sick during a mission. To minimize the chances of that, they typically spend the two weeks before launch in quarantine. A Covid-19 superspreader event at the space station would disrupt operations. The interior of the space […]
