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Ed Stone, JPL director and top scientist on Voyager mission, dies at 88

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Ed Stone, JPL director and top scientist on Voyager mission, dies at 88

Ed Stone, the scientist who guided NASA’s breakthrough Voyager mission to the outer planets for 50 years and led the Jet Propulsion Laboratory when it landed its first rover on Mars, died Tuesday. He was 88.

A physicist who got in on the ground floor of space exploration, Stone played a leading role in NASA missions to Mars, Jupiter, Saturn, Uranus and Neptune. The discoveries made under his watch revolutionized scientists’ understanding of the solar system and fueled humanity’s ambition to explore distant worlds.

Carolyn Porco, who worked on imaging on JPL’s Voyager and Cassini missions, called Stone “a thoroughly lovely man” who was “as close to perfect as a project scientist could ever be.”

“When two science teams were in contention over some spacecraft resource, and Ed had to decide between the two, even the guy who lost went away thinking, ‘Well, if this is what Ed has decided, then it must be the right answer,’” Porco said by email Tuesday. “I feel blessed to have known Ed. And like many people today, I’m very sad to know he’s gone.”

Stone was a 36-year-old Caltech physics professor in 1972 when he was asked to serve as chief scientist for an audacious plan to send a pair of spacecraft to explore the solar system’s four giant planets for the first time.

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It was the opportunity of a lifetime, but he wasn’t sure he wanted the gig.

“I hesitated because I was a fairly young professor at that point. I still had a lot of research I wanted to do,” he recalled 40 year later.

He took it anyway, and from the mission’s first encounter with Jupiter in 1979 to its final flyby of Neptune in 1989, Stone became the scientific face of the Voyager mission. He guided the science agenda and helped the public make sense of revolutionary images and data not just from Jupiter, Saturn, Uranus and Neptune, but from many of their fascinating moons.

Stone and his more than 200 science collaborators were the first to discover lightning on Jupiter and volcanoes on its moon Io. They spotted six never-before-seen moons around Saturn and found evidence of the largest ocean in the solar system on Jupiter’s moon Europa, as well as geysers on Neptune’s moon Triton.

“It seemed like everywhere we looked, as we encountered those planets and their moons, we were surprised,” Stone told the Los Angeles Times in 2011. “We were finding things we never imagined, gaining a clearer understanding of the environment Earth was part of. I can close my eyes and still remember every part of it.”

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The Voyager 1 spacecraft became the first manmade object to reach interstellar space in 2012, and Voyager 2 followed suit in 2018.

Stone, pictured with a model of the Voyager spacecraft, said the discovery of volcanoes on Io was a highlight of the mission.

(NASA)

The twin probes continue to send weekly communications to Earth from interstellar space. Stone retired in 2022 on the mission’s 50th anniversary.

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“A part of Ed lives on in the two Voyager spacecraft. The fingerprints of his dedication and keen leadership are woven into the Voyager mission,” said Linda Spilker, who joined the mission in 1977 and succeeded him as project scientist.

The Voyager mission was Stone’s crowning achievement, but hardly his only one.

He was a principal investigator on nine NASA missions and a co-investigator on five others, including several satellites designed to study cosmic rays, the solar wind and the Earth’s magnetic field.

He became director of the Jet Propulsion Laboratory in La Cañada Flintridge in 1991, a role he held for a decade.

It was an era of cost-cutting at NASA, but Stone still managed to launch Galileo’s five-year mission to Jupiter and send the Cassini spacecraft to Saturn. He was also at the agency’s helm when Mars Pathfinder delivered the Sojourner rover to the Red Planet. It marked the first time that humans had put a robotic rover on the surface of another planet.

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Throughout his tenure at JPL, Stone continued to work and teach at Caltech, even teaching freshman physics during some of Voyager’s long cruise times between planets.

He also served as chairman of the board of the California Assn. for Research in Astronomy, which is responsible for building and operating the W.M. Keck Observatory and its two 10-meter telescopes on Mauna Kea, Hawaii.

Edward Carroll Stone Jr. was born in Iowa on Jan. 23, 1936, and grew up in Burlington, where his father ran a small construction business and his mother kept the company books.

The eldest of two brothers, Stone was attracted to science from a young age. Under his father’s watchful eye, he learned how to take apart and reassemble all varieties of technology, from radios to cars.

“I was always interested in learning about why something is this way and not that way,” Stone told an interviewer in 2018. “I wanted to understand and measure and observe.”

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After studying physics at Burlington Junior College, he received his master’s and doctorate at the University of Chicago. Shortly after he began his graduate studies, news broke in 1957 that the former Soviet Union had launched Sputnik, the world’s first artificial satellite.

“Just like that, because of the Cold War and our need to match Sputnik, a whole new realm absolutely opened up,” he said.

Stone built a device for measuring the intensity of solar energetic particles above the atmosphere that hitched a ride to space aboard an Air Force satellite in 1961. Unfortunately the spacecraft’s transmitter didn’t work, so only a very limited quantity of data was returned to Earth. However, it was still enough to indicate that the intensity of the particles was lower than expected.

Despite the transmitter glitch, Stone said the project was thrilling. “We were taking the first steps in a whole new area of research and exploration,” he said. “We were right at the beginning.”

He joined the faculty at Caltech in 1964 and created more space experiments, this time for NASA.

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Stone’s particular area of interest was cosmic rays — high-speed atomic nuclei that can originate from explosive events on the sun or from violent events beyond the solar system.

One of his cosmic-ray experiments was included among the 11 major Voyager experiments.

Ed Stone gestures in front of a reddish background

Ed Stone in 2011, about a year before Voyager 1 entered interstellar space.

(Al Seib / Los Angeles Times)

Colleagues praised Stone for his leadership of the Voyager science team.

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“He was a great hero, a giant among men,” said Porco, adding that Stone was known to treat everyone — from top scientists to graduate students — with respect.

Voyager team scientist Thomas Donahue put it this way: “Over the years, Ed Stone has proved to be remarkably adept at keeping a bunch of prima donnas on track.”

Stone was elected to the National Academy of Sciences in 1984 and received the National Medal of Science from President George H.W. Bush in 1991 in recognition of his leadership of the Voyager mission. He won the Shaw Prize in Astronomy in 2019, an honor that comes with a $1.2-million award. In 2012 his hometown of Burlington, Iowa, named its new middle school after him.

“This is truly an honor because it comes from the community where my exploration journey began,” Stone told a local newspaper.

Decades after Voyager’s launch he was asked to select his favorite moment from the mission. He chose the discovery of volcanoes on Jupiter’s moon Io.

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“Finding a moon that’s 100 times more active volcanically than the entire Earth, it’s really quite striking,” he said. “And this was typical of what Voyager was going to do on the rest of its journey through the outer solar system.

“Time after time, we found that nature was much more inventive than our models,” he said.

His wife, Alice, whom he met on a blind date at the University of Chicago and married in 1962, died in December. The couple are survived by their two daughters, Susan and Janet Stone, and two grandsons.

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Doctor surrenders license after allegations that he sexually abused patients and employees

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Doctor surrenders license after allegations that he sexually abused patients and employees

A longtime internist who founded a chain of Southern California clinics has surrendered his medical license after an accusation from the state medical board that he sexually assaulted three patients, two of whom worked for his clinics.

Dr. Mohammad Rasekhi signed an agreement to give up his medical license last month, weeks after the Medical Board of California filed an accusation against him detailing allegations that Rasekhi sexually abused three women while they were under his care.

Rasekhi denies all the allegations, his attorney Peter Osinoff said this week. He chose to waive his rights to a hearing and retire from medicine, a decision Osinoff said his client had been considering for some time.

“For him to spend his retirement money litigating over a license he no longer uses is not a good use of money,” Osinoff said. The surrender took effect Dec. 2.

Rasekhi was the founder and chief medical officer of Southern California Medical Center, a group of general practice clinics with locations in El Monte, Van Nuys, Pico Rivera, Woodland Hills, Pomona and Long Beach.

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Sheila Busheri, co-founder of Southern California Medical Center and Rasekhi’s spouse, declined to comment.

In a document filed Oct. 3, the state medical board accused Rasekhi of sexual exploitation and gross negligence in his treatment of three patients.

The first became a primary care patient of Rasekhi’s around 2005, when she was 12 years old. In 2016, she accepted a job at SCMC while still seeing Rasekhi for her medical care.

Soon after, Rasekhi began making sexually suggestive comments to her at work, the document states. These progressed to unwanted sexual contact the woman endured for fear of losing her job, according to the complaint. The abuse continued until she went on medical leave in 2020.

The medical board reviewed records of the woman’s doctor appointments with Rasekhi. According to her chart, Rasekhi performed breast exams on the patient during visits for seemingly unrelated complaints such as back pain and hair loss, the accusation states.

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“Respondent denied performing breast exams during those visits and conceded that the medical record does not accurately reflect the details about the visit or the examinations actually performed,” the complaint states.

A second patient began seeing Rasekhi in 2016 at the age of 62. In September 2017, the complaint states, Rasekhi arrived unannounced at the patient’s home.

“After entering Patient 2’s home and without Patient 2’s consent and over Patient 2’s protests, Respondent made sexual advances towards, and had sexual contact with, Patient 2,” the complaint said.

A third patient was employed at SCMC from 2007 to 2017, and became a patient of Rasekhi’s in 2015. Rasekhi made frequent suggestive comments at work that escalated into advances and sexual contact that continued until her resignation, the complaint stated.

A woman whose employment dates matched those of the third patient settled with Rasekhi, Busheri and SCMC for $3.5 million in 2019, according to a report in the Daily Journal.

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Avocados, salmon, strawberry yogurt: Which of these meets FDA's new definition of a “healthy” food?

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Avocados, salmon, strawberry yogurt: Which of these meets FDA's new definition of a “healthy” food?

In an effort to improve American diets, the U.S. Food and Drug Administration Thursday released a new definition of what it means for a food to qualify as “healthy.”

Products like fruit-flavored yogurt, fortified white bread and sweetened energy bars will no longer be allowed to label themselves as healthy if they exceed certain limits on saturated fat, sodium and added sugars.

At the same time, foods like salmon, almonds and even water will qualify as healthy for the first time.

The new definition reflects the advice offered in the Dietary Guidelines for Americans, which are produced by the Department of Agriculture and the Department of Health and Human Services. The hope is that consumers who consider health claims on packaged foods while filling their grocery carts will be steered toward a more nutritious eating pattern, the FDA said.

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There’s no question that Americans can use some help with their diets. For example, less than half of U.S. adults eat a piece of fruit on any given day, and only 12% consume the recommended 1.5 to 2 cups of fruit per day, according to national surveys conducted by the Centers for Disease Control and Prevention. Americans are even further off the mark with vegetables, with only 10% meeting the target of 2 to 3 cups per day.

On the other hand, 90% of us eat too much sodium, 75% eat too much saturated fat and 63% eat too many added sugars, the FDA said.

The new definition of healthy foods aims to turn that around by excluding foods with excess sodium, saturated fat and added sugars even if they also contain valuable nutrients like protein and whole grains.

The specific limits vary depending on food groups. The limits will also depend on whether a product is an individual food (like cheese), a “mixed product” (like trail mix) or a complete meal (like a frozen dinner).

For instance, in order for a dairy product such as yogurt to qualify as healthy, a single 2/3-cup serving can’t have more than 5% of the recommended daily amount of added sugars, 10% of the recommended daily amount of sodium or 10% of the recommended daily amount of saturated fat.

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Those limits translate to 2.5 grams of added sugars, 230 milligrams of sodium and 2 grams of saturated fat. A single serving of Chobani strawberry Greek yogurt would miss the mark because it contains 9 grams of added sugars. So would Chobani’s “less sugar” variety, which has 5 grams of added sugars.

Sugar, salt and fat are only part of the new criteria. To meet the new definition of healthy, foods must contain a minimum amount of protein, whole grains, fruit, vegetables or fat-free or low-fat dairy, the FDA said.

Whole foods like eggs, beans, seafood and nuts will automatically qualify as healthy if they are sold with no added ingredients (except for water). That makes foods like avocados, olive oil and higher-fat fish like salmon eligible to be labeled as healthy for the first time. Fruits, vegetables and fish can make the cut if they are fresh, frozen or canned, making them accessible to people on a range of budgets, the agency said.

However, products like fortified breads, cereals, fruit snacks, granola bars and fruit punch will lose the label unless they are reformulated to meet the new definition.

Nancy Brown, chief executive of the American Heart Assn., said the new definition was long overdue and hopes it will improve Americans’ diets by motivating food manufacturers to create healthier products. However, she added that it would be more meaningful to require products to carry a nutrition label on the front of their packages, which she believes would make it easier for consumers to identify and select healthier options.

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The previous definition of healthy foods, which was issued in 1994, focused more on total fat and cholesterol. Since then, nutrition scientists have recognized that not all fats should be treated the same, and that unsaturated fats found in nuts, seeds, fish and certain vegetable oils can lower disease risk.

The old definition also required foods to provide at least 10% of the recommended daily amount of vitamin A, vitamin C, calcium, iron, protein or fiber. The FDA said it is shifting its focus from specific nutrients to larger food groups in order to help consumers build a healthy dietary pattern.

Poor diet is a risk factor for many of the leading causes of death in the U.S., including heart disease, stroke, diabetes and some types of cancer.

Food manufacturers will have three years to conform to the new definition, the FDA said, though those that meet the new criteria don’t have to wait that long to start using the “healthy” label.

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I'm a woman in my 40s. Why do I feel terrible every time I have a drink?

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I'm a woman in my 40s. Why do I feel terrible every time I have a drink?

This summer an old high school friend of mine decided to quit drinking entirely. She didn’t want to, but she felt she had no choice.

“All of a sudden my body decided that alcohol is poison,” she told me recently over a bitter grapefruit mocktail at an Italian restaurant. “I can have as little as one drink, and I have a hangover.”

Like me, my high school friend was never a heavy drinker. She enjoyed having a glass of wine with dinner and a craft cocktail or two at a bar or restaurant with friends. If she had several drinks in a night she would expect to feel sluggish in the morning, but one or two was never a problem. Then, sometime in her mid-40s, her ability to tolerate alcohol plummeted.

“It’s that feeling of regret,” she said when I asked her about her post-drinking symptoms. “Headache, fatigue, I don’t know how to name that feeling in your stomach.”

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The last time she had a margarita she felt so terrible that she ended up canceling her plans the following evening.

It’s a story I’ve been hearing from a growing number of my female friends since we entered our mid-40s a few years ago. Molly finds drinking wreaks havoc with her digestive system and her sleep. Alexis loads up on water and Motrin even if all she’s had was a half-glass of wine. Naama, who still makes the world’s most delicious batch cocktails, stopped drinking a few years ago after getting the sweats and a splitting headache halfway through a vodka soda.

I’ve experienced it as well. After even one drink, I find myself waking up at 3 in the morning with a dull ache in my stomach, wishing I’d made a different choice. Now, each opportunity to grab a beer at a barbecue, enjoy a cocktail at a restaurant or sip a glass of wine at a dinner party requires a cost-benefit analysis: How much do I want a drink now versus but how much am I willing to pay for it later?

To understand why my friends and I are finding alcohol more difficult to tolerate as we age, I reached out to George F. Koob, director of the National Institute on Alcohol Abuse and Alcoholism.

Koob pointed to studies that show that women are more sensitive to the toxic effects of alcohol — developing alcohol-related liver disease and high blood pressure due to drinking at higher rates than men — but added that scientists are still working out why that seems to be the case.

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“This is a new area of research,” he said.

While Koob wasn’t aware of studies that looked specifically at how a woman’s ability to metabolize alcohol changes in middle age, he said any changes may be due in part to the natural and inevitable fact that our lean muscle mass decreases and our body fat increases as we get older.

“You might drink the same amount of alcohol that you used to drink, but now that one drink is more like having one and a half or two drinks, because the alcohol is hanging out in the bloodstream.”

— George F. Koob, director of the National Institute on Alcohol Abuse and Alcoholism

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Alcohol is drawn to water, Koob explained, and lean muscle mass has a higher percentage of water than fat does. Lean muscle mass, then, gives alcohol more space to dissipate throughout the body, making for less of it in the bloodstream, and a lower blood alcohol concentration. But as we age and lose lean muscle mass and gain fat, a higher concentration of alcohol winds up in our bloodstream. That makes for worse hangovers and extended recovery time.

“You might drink the same amount of alcohol that you used to drink, but now that one drink is more like having one and a half or two drinks, because the alcohol is hanging out in the bloodstream,” he said.

If it makes you feel any better, men also lose lean muscle mass and gain fat as they age, but men’s bodies have a higher concentration of water (55% to 65%) compared with women (45% to 50%) to begin with, so the effects may not be as obvious as they are for us.

Koob supports finding alternatives to drinking — “If you feel better when you don’t drink, then listen to your body,” he said. If you are going to drink, he offered that eating a snack beforehand can slow down the body’s absorption of alcohol and help blunt the irritation to the stomach that can cause the icky feeling I know so well. He also advised against using ibuprofen immediately after drinking, because it can also irritate the stomach. Drinking extra water will help dilute the alcohol, but ultimately, it’s the amount of alcohol you drink that will affect how you feel, not how much water you drink.

Because my friends and I are also firmly in the perimenopausal phase of our lives, I called up Dr. Monica Christmas, associate professor of obstetrics and gynecology at the University of Chicago and associate medical director of the Menopause Society, to see if our new challenges with alcohol might be related to hormonal changes as well.

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The answer was a resounding yes.

She explained that alcohol triggers or exacerbates many of the symptoms of both menopause and “the menopause transition,” which can begin seven to 10 years before a woman’s period actually stops.

For example, 40% of women report mood instability during the menopause transition, which can include increased anxiety, depression, or not being motivated to do the things they once did.

“Alcohol exacerbates those things,” Dr. Christmas said. “So if you’re already experiencing mood instability, you’re only going to feel that much worse when you drink alcohol.”

I haven’t noticed my anxiety skyrocketing after having a drink or two, but my high school friend said that sounded familiar.

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“There was an evil loop I was in, where I was like, I’m really anxious, maybe I’ll have another drink,” she said. “My husband was like, how’s that working out for you?”

To be clear, not all my friends feel this way. Some who have always consumed alcohol more regularly looked at me quizzically when I asked if they find it harder to drink these days. It’s possible they have developed a physiological tolerance to alcohol or may just be more used to hangovers, said MacKenzie Peltier, an assistant professor of psychiatry at Yale School of Medicine who studies sex differences in alcohol abuse disorders. It might also be that their experiences of the menopausal transition or aging are different. “But that’s complete speculation,” she said.

As for the rest of my friend group, we’re all handling this frankly unwelcome change in different ways. My high school friend has become a mocktail connoisseur. Molly hasn’t cut out alcohol completely, but she does do dry months to give her body a break. Alexis recently decided not to drink during the week anymore, but weekends are still up for debate. Naama is always on the hunt for a fancy nonalcoholic drink with low sugar content to sip at celebratory occasions.

“The only time I miss it is when we’re out with friends and the only option is Diet Coke,” she said. “And God forbid if that option is only Diet Pepsi. Then I’m really screwed.”

As for me, I’m trying to minimize the temptation to consume alcohol. Not only are pre-dinner cocktails expensive from a financial standpoint, they’re costly from a health perspective, too.

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I do still love to have a drink at my Italian social club, however, and if that means a couple of rough nights a month in order to enjoy an Aperol Spritz or two — for me, that’s a trade-off I’m willing to make.

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