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After months of silence, Voyager 1 has returned NASA's calls

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After months of silence, Voyager 1 has returned NASA's calls

For the last five months, it seemed very possible that a 46-year-old conversation had finally reached its end.

Since its launch from Kennedy Space Center on Sept. 5, 1977, NASA’s Voyager 1 spacecraft has diligently sent regular updates to Earth on the health of its systems and data collected from its onboard instruments.

But in November, the craft went quiet.

Voyager 1 is now some 15 billion miles away from Earth. Somewhere in the cold interstellar space between our sun and the closest stars, its flight data system stopped communicating with the part of the probe that allows it to send signals back to Earth. Engineers at the Jet Propulsion Laboratory in La Cañada Flintridge could tell that Voyager 1 was getting its messages, but nothing was coming back.

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“We’re to the point where the hardware is starting to age,” said Linda Spilker, the project scientist for Voyager mission. “It’s like working on an antique car, from 15 billion miles away.”

Week after week, engineers sent troubleshooting commands to the spacecraft, each time patiently waiting the 45 hours it takes to get a response here on Earth — 22.5 hours traveling at the speed of light to reach the probe, and 22.5 hours back.

By March, the team had figured out that a memory chip that stored some of the flight data system’s software code had failed, turning the craft’s outgoing communications into gibberish.

A long-distance repair wasn’t possible. There wasn’t enough space anywhere in the system to shift the code in its entirety. So after manually reviewing the code line by line, engineers broke it up and tucked the pieces into the available slots of memory.

They sent a command to Voyager on Thursday. In the early morning hours Saturday, the team gathered around a conference table at JPL: laptops open, coffee and boxes of doughnuts in reach.

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At 6:41 a.m., data from the craft showed up on their screens. The fix had worked.

“We went from very quiet and just waiting patiently to cheers and high-fives and big smiles and sighs of relief,” Spilker said. “I’m very happy to once again have a meaningful conversation with Voyager 1.”

Voyager 1 is one of two identical space probes. Voyager 2, launched two weeks before Voyager 1, is now about 13 billion miles from Earth, the two crafts’ trajectories having diverged somewhere around Saturn. (Voyager 2 continued its weekly communications uninterrupted during Voyager 1’s outage.)

They are the farthest-flung human-made objects in the universe, having traveled farther from their home planet than anything else this species has built. The task of keeping communications going grows harder with each passing day. Every 24 hours, Voyager 1 travels 912,000 miles farther away from us. As that distance grows, the signal becomes slower and weaker.

When the probe visited Jupiter in 1979, it was sending back data at a rate of 115.2 kilobits per second, Spilker said. Today, 45 years and more than 14 billion miles later, data comes back at a rate of 40 bits per second.

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The team is cautiously optimistic that the probes will stay in contact for three more years, long enough to celebrate the mission’s 50th anniversary in 2027, Spilker said. They could conceivably last until the 2030s.

The conversation can’t last forever. Microscopic bits of silica keep clogging up the thrusters that keep the probes’ antennas pointed toward Earth, which could end communications. The power is running low. Eventually, the day will come when both Voyagers stop transmitting data to Earth, and the first part of their mission ends.

But on the day each craft goes quiet, they begin a new era, one that could potentially last far longer. Each probe is equipped with a metallic album cover containing a Golden Record, a gold-plated copper disk inscribed with sounds and images meant to describe the species that built the Voyagers and the planet they came from.

Erosion in space is negligible; the images could be readable for another billion years or more. Should any other intelligent life form encounter one of the Voyager probes and have a means of retrieving the data from the record, they will at the very least have a chance to figure out who sent them — even if our species is by that time long gone.

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RFK Jr. announces a plan to ban certain food dyes, following California's lead

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RFK Jr. announces a plan to ban certain food dyes, following California's lead

Robert F. Kennedy Jr., the secretary of Health and Human Services, on Tuesday announced a plan to ban synthetic food dyes that color everyday snack items such as Flamin’ Hot Cheetos and M&Ms.

The first step in the plan is for the U.S. Food and Drug Administration to revoke authorization of citrus red No. 2 and orange B.

After that, the Department of Health and Human Services said, it will work with industry to eliminate six petroleum-based food dyes: blue 1, blue 2, green 3, red 40, yellow 5 and yellow 6.

California passed a law banning those six dyes last year, citing developmental and behavioral harms in children. The state law is set to go into effect the end of 2027.

The FDA is instead encouraging the use of so-called natural food dyes such as gardenia blue and calcium phosphate. “Red dye? Try watermelon juice or beet juice,” FDA Commissioner Marty Makary said at the media event, holding up a jar of crimson liquid.

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The announcement Tuesday is meant to spur the food dye industry to cooperate in eliminating those dyes by the end of next year, according to the department.

“Let’s start in a friendly way and see if we can do this without any statutory or regulatory changes,” Makary said. “They want to do it.”

Makary noted at the event that he worked with government officials in California to develop these proposed federal changes.

Food dyes have been under scrutiny for years, as consumer advocate groups have said they contain additives harmful to humans. In January, the FDA banned red dye no. 3 — used in such common items as fruit-cocktail cherries and Nesquik’s strawberry milk — after some studies showed that the additive raised the risk of cancer in some lab animals.

In keeping with Kennedy’s mission to eliminate synthetic food dyes as soon as possible, the department announcement also calls for food companies to get rid of red no. 3 in their products sooner than the previously agreed-upon deadline. (California banned the use of red 3 in 2023; that law is also set to go into effect in 2027.)

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Kennedy has blamed food additives for myriad health issues. His supporters heralded the announcement Tuesday as a major step in the secretary’s movement to “Make America Healthy Again.” A Gallup poll last year found that 28% of respondents did not have much confidence in the federal government’s ability to ensure the food supply is safe. An additional 14% had no confidence at all.

“Industry is making money to keep us sick,” Kennedy said at the announcement.

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Mexican child infected with H5N1 bird flu dies from respiratory complications

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Mexican child infected with H5N1 bird flu dies from respiratory complications

A 3-year-old girl in Mexico died this month after getting infected with H5N1 bird flu, according to a report issued by the World Health Organization this week.

Authorities say the strain of bird flu is one that has been circulating in wild birds throughout North America, known as D1.1. It is the same strain implicated in the death of a person in Louisiana earlier this year, and in the case of a 13-year-old Canadian who was placed on life-support for several weeks before recovering.

Two others, a person in Wyoming and a poultry worker in Ohio, were also reported to have severe disease after exposure to this strain of the virus.

The strain has been detected in dairy herds from Nevada and Arizona.

“The case in Mexico is another great reminder of how dangerous H5 viruses can be,” said Richard Webby, an infectious disease expert at St. Jude Children’s Research Hospital in Memphis, Tenn.

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The D1.1 strain is widespread in the U.S. and Canada, but until this week’s WHO report it was unclear how far south the strain had traveled, he said.

“It has been a very active virus to date,” he said, and “further spread will undoubtedly lead to more infections, both in birds and humans. “

He said researchers are now awaiting publication of the genetic sequence, which will provide more information about whether there have been further changes that could make it more severe and/or transmissible.

According to the WHO, the young girl’s symptoms, which included fever, malaise and vomiting, began on March 7. She was admitted to a hospital in the state of Durango on March 13 due to respiratory failure. She was treated with oseltamivir, an antiviral drug, the following day. On March 16, she transferred to another hospital in the city of Torreón.

She died on April 8 from “respiratory complications.”

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The girl did not have any underlying medical conditions, had not received a seasonal influenza vaccination, and had no history of travel, according to the WHO report.

The source of the child’s infection remains under investigation.

According to the report, 91 people were identified as contacts of the toddler, including 21 household contacts, 60 healthcare workers and 10 people from a childcare center. Each of these people was tested and all have tested negative for the virus.

Between 2022 and August 2024, there have been 75 reported H5N1 poultry outbreaks across Mexico, although none in Durango. At the end of January 2025, a sick vulture at the Sahuatoba Zoo, in Durango, was diagnosed with the virus. In addition, dozens of wild birds in the state were also reported, including a Canada goose.

The virus is still circulating in U.S. dairy herds, poultry, wild birds and wild mammals. Since April 1, there have been five new reports of infected dairy herds from California, 15 in Idaho and one from Arizona, according to the US Department of Agriculture.

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There have also been dozens of domestic cats infected with the virus, including three recent reports from California’s Orange and Alameda counties: two in Orange and one in Alameda.

According to the U.S. Centers for Disease Control and Prevention, there have been 70 reported cases of H5N1 bird flu in the U.S. since March 2024, when the virus was first reported in dairy herds. There has been one death, a person older than 65 from Louisiana.

Health officials say the risk of H5N1 bird flu to the general public remains low and there has been no indication of person-to-person spread. Most cases have been associated with contact with infected livestock and poultry.

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A 'calamity waiting to unfold': Altadena residents with standing homes fear long-term health effects

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A 'calamity waiting to unfold': Altadena residents with standing homes fear long-term health effects

On Jan. 7, two residents on opposite sides of Altadena — Francois Tissot, a Caltech professor who studies the geology of ancient Earth and our solar system, living in the east side of town; and Jane Potelle, an environmental advocate living in the west side — fled the intensifying red glow of the devastating Eaton fire.

The inferno devoured home after home, unleashing what experts estimate to be tons of dangerous metals and compounds, from lead to asbestos to the carcinogen benzene. Carried through the vicious winds, the toxins embedded deep into the soil, seeped into the blood of first responders, and leaked into structures in the area that hadn’t burned down.

Within weeks, Altadena residents whose homes had withstood the fire began to return — yet few were testing for contaminants both Tissot and Potelle knew were almost certainly sitting in their still-standing houses.

Working independently, they both decided to create a comprehensive picture of the contamination lurking within surviving homes, both in the burn area and miles outside it.

They came to similar results: In the houses inside the burn zone, there was lead — a metal capable of dealing irreversible damage to the brain and nervous system — at levels far exceeding 100 times the Environmental Protection Agency’s allowable limits. Tissot’s group also found lead levels exceeding the limit over five miles from the fire’s perimeter.

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“Children exposed to lead will have diminished cognitive development,” said Tissot, referencing studies that found exposure to leaded gasoline in though the 1990s was correlated with a drop in children’s IQ (an imperfect but useful metric for reasoning ability) by up to seven points.

“To me, what’s at stake is the future of a generation of zero- to 3-year-olds,” Tissot said. “If nothing is done, then these children will be exposed. But it’s totally avoidable.”

Activists and community leaders, along with residents who were force to evacuate when the Eaton fire swept through the city of Altadena, gather at an apartment complex where several residents are living with little to no utilities.

(Jason Armond/Los Angeles Times)

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Potelle, frustrated with the lack of government response to contamination concerns, started a grassroots organization with other Altadena residents with standing homes to collect and publish tests conducted by certified specialists.

The organization, Eaton Fire Residents United, or EFRU, found lead in every single one of the 90 homes for which they’ve collected test results. Of those, 76% were above the EPA limits.

EFRU and Tissot’s team were distressed by these data, particularly seeing debris-removal and remediation contractors work without masks in the burn area and some residents even begin to return home.

In early April, Anita Ghazarian, co-lead of EFRU’s political advocacy team, went back to her standing home within the burn zone to pick up mail. She watched as a grandmother pushed a toddler in a stroller down the street.

“She has no idea … this area is toxic,” Ghazarian recalled thinking. The gravity of the situation sunk in. “To me, it’s just — unfortunately — a calamity waiting to unfold.”

Evidence mounted in the 1950s that even small amounts of lead exposure could harm children’s brains. But by the time the U.S. banned lead in paint in 1978, roughly 96% of the homes in Altadena that burned in the Eaton fire were already built. In the Palisades, that number was 78% — smaller, but still significant.

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Jared Franz looks at the state of his kitchen.

Jared Franz looks at the state of his kitchen, which survived the Eaton Fire, but is inhabitable due to smoke damage.

(William Liang/For The Times)

Dust from the fire inside the Franz family's home.

Dust from the fire inside the Franz family’s home.

(William Liang/For The Times)

After the Eaton fire, Tissot did a quick back-of-the-envelope calculation to understand what his Altadena community might be dealing with: roughly 7,000 homes burnt with 100 liters of paint per house and 0.5% of that paint likely made of lead.

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“That’s something like several tons of lead that have been released by the fire, and it’s been deposited where the fire plume went,” he said.

As the Eaton fire roared in the foothills of the Angeles National Forest the night of Jan. 7, Tissot fled with his two kids, along with the rest of east Altadena.

Meanwhile, Potelle sat awake in her living room on the west side of town, listening to the howling winds as the rest of her family slept.

When Potelle got the evacuation order on her phone around 3:30 a.m. Jan. 8, her family joined the exodus. As they raced to gather their belongings, Potelle grabbed protective goggles she had bought for her son’s upcoming Nerf-battle birthday party.

Even with them, the soot, smoke and ash made it impossible to see.

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The family made it to a friend’s house in Glendale, but as the toxic smoke plume swelled, Potelle had to evacuate yet again, this time to a friend’s garage. Tissot, then in Eagle Rock, left for Santa Barbara the next day as the smoke’s incursion progressed southwest.

As Altadena turned into a ghost town on Jan. 9, some residents — including Potelle’s husband — crept back in to assess the damage. Potelle waited for her husband’s report and watched on social media from the safety of the garage.

“People are just videotaping themselves driving through Altadena, and it’s block after block after block of burnt-down homes. The reality of it started to strike me,” Potelle said. “This is not just carbon. This is like, refrigerators and dishwashers and laundry machines and dryers and cars.”

Fires like these, with smoke made of car batteries, paints, insulation and appliances — and not trees and shrubs — are becoming increasingly common in California. These fuels can contain a litany of toxic substances like lead and arsenic that are not present in vegetation, waiting to be unlocked by flame.

Potelle’s home sustained visible smoke damage. So, she made two trips to a disaster support center set up temporarily at Pasadena City College, hoping to get support from her insurance company and the government for soil and in-home contamination testing.

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Officials directed Potelle back and forth between her insurance company, FEMA, the L.A. County Department of Public Health, and the California Department of Insurance. Potelle — who, at this point, had already started to develop a cough and chest pain, which she suspects came from her visits to the burn area — left with without clear answers, feeling dejected.

“I’m driving, going back to my friend’s garage … and I’m just realizing there’s no one looking out for us,” she said.

Potelle set out to find the answers herself.

“Here’s the thing, if you don’t know what’s in your home when you remediate, you could just be pushing those contaminants deeper into your walls, deeper into your personal items,” Potelle said.

Tissot, meanwhile, visited his home a week after the fires to find the windows exploded, melted or warped; the walls cracked; and ash and soot everywhere. He too decided that he ought to do his own testing for contamination.

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In his day job, Tissot runs a lab with sophisticated machinery able to discern what metals are present in samples of material, usually comprised of rock and dirt, based on their atomic mass: Only lead has an atomic mass of 0.34 trillion billionths of a gram. He normally uses the machine to study rare elements and isotopes from space and eons ago.

He gathered his lab team together on the Caltech campus to use the equipment to test samples from their own backyard.

The team took 100 samples from windowsills, desks and stairwells in the Caltech geology and planetary science buildings. Some surfaces were untouched since the fire; others had been cleaned by Caltech’s trained custodians.

For the record:

5:56 p.m. April 16, 2025A previous version of this article incorrectly stated that the Caltech team had tested samples from uncleaned surfaces, then cleaned those surfaces and took second samples. The Caltech team tested some samples from surfaces untouched since the fire, and some from surfaces that had been cleaned by Caltech’s trained custodians.

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The team found multiple uncleaned surfaces with lead levels above the EPA’s limits. And while the cleaned surfaces had about 90% less lead, some still exceeded the limits.

Tissot quickly set up a webinar to announce the findings. The chat exploded with requests from homeowners in Altadena asking Tissot to test their houses.

Around the same time, Potelle noticed some folks on Facebook sharing the results of in-home contamination testing — which in many cases, they had paid for out of pocket.

Inspired, she advertised a Zoom meeting to discuss a strategy for mapping the test results. Sixty residents showed up; Potelle coordinated the group so that residents could submit results to EFRU’s Data Unification team for analysis.

Meanwhile, Tissot connected with residents who messaged him to set up a testing campaign. The researchers donned full hazmat suits in early February and entered the burn area to test homes and meet with homeowners.

ERFU posted its first dataset of 53 homes on March 24. Tissot’s group announced their results, which included data from 52 homes, just a week later, confirming what many had feared: There was lead everywhere.

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“What was surprising to me is how far it went,” said Tissot. “We got very high levels of lead even miles away from the fire, and what’s difficult is that we still can’t really answer a simple question: How far is far enough to be safe?”

The two groups hope their data can help homeowners make better-informed decisions about their remediation and health — and apply pressure on leaders to take more action.

Tissot wants to see the government update its guidebooks and policy on fire recovery to reflect the contamination risks for intense urban fires, and to require testing companies to report their results to a public database.

Nicole Maccalla, a core member of EFRU’s Data Unification team, hopes to see officials enforce a common standard for insurance claims for testing and remediation so every resident doesn’t have to go through the same exact fight.

“You’ve got people stepping up to fill the void,” she said. “There should be an organized, systematic approach to this stuff, but it’s not happening.”

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Times data journalist Sandhya Kambhampati contributed to this report.

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