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NASA clears $5 billion Jupiter mission for launch after review of suspect transistors

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NASA clears $5 billion Jupiter mission for launch after review of suspect transistors


After an exhaustive review of suspect transistors in NASA’s Europa Clipper spacecraft, NASA managers have cleared the probe for launch next month as planned on a $5.2 billion mission to find out if a suspected sub-surface ocean on Jupiter’s icy moon Europa is a habitable environment.

The transistor issue cropped up in May, raising fears the scope of the Clipper’s mission might have to be reduced or the flight delayed for costly repairs.

But the review showed the transistors in question will, in effect, heal themselves during the 20 days between the high radiation doses the probe will receive during each of 49 close flybys of Europa, all of them deep in Jupiter’s powerful magnetic field and radiation environment.

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An artist’s impression of NASA’s Europa Clipper spacecraft making a close flyby of Jupiter’s moon Europa. Equipped with state-of-the-art instrument, the probe will attempt to determine if a vast sub-surface ocean below Europa’s ice crust might provide a habitable environment for life.

NASA


In addition, onboard heaters can be used as needed to raise the temperature of affected transistors, improving the recovery process.

“After extensive testing and analysis of the transistors, the Europa Clipper project and I personally have high confidence we can complete the original mission for exploring Europa as planned,” said Jordan Evans, Europa Clipper project manager at NASA’s Jet Propulsion Laboratory.

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The solar-powered Europa Clipper, one of NASA’s most ambitious planetary probes, is a “flagship” mission designed to make multiple close flybys of Europa to learn whether a subsurface salt water ocean beneath the frozen world’s icy crust could host a habitable environment.

If habitability can be confirmed, “just think of what that means, that there are two places in one solar system that have all the ingredients for life that are habitable right now at the same time,” said Curt Niebur, Europa Clipper program scientist at NASA Headquarters.

“Think of what that means when you extend that result to the billions and billions of other solar systems in this galaxy. Setting aside the ‘is there life?’ question on Europa, just the habitability question in and of itself opens up a huge new paradigm for searching for life in the galaxy.”

Discovered in 1610 by Galileo, Europa has been studied by NASA’s Voyager probes and, much more extensively, by the agency’s aptly-named Galileo orbiter in the 1990s, which made a dozen close flybys.

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The spacecraft discovered that Jupiter’s magnetic field was disrupted around Europa, implying an electrically conductive fluid deep within the moon. Given Europa’s frozen crust, the most likely explanation is a sub-surface salt water ocean, kept warm by tidal flexing, the repetitive squeezing by Jupiter’s enormous gravity as the moon swings through its orbit.

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A closeup showing a chaotic jumble of huge, icy slabs making up Europa’s frozen surface as imaged by NASA’s Galileo spacecraft more than two decades ago.

NASA


The Europa Clipper is not designed to search for signs of life on or below Europa’s crust. But confirming the presence of a hidden sea and determining its habitability would be a major step forward in the search for places in the solar system and beyond where life, as currently defined, could exist.

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“This is an epic mission,” Niebur said. “It’s a chance for us to explore not a world that might have been habitable billions of years ago, but a world that might be habitable today, right now,”

“A chance to do the first exploration of this new kind of world that we’ve discovered very recently called an ocean world, that is just totally immersed and covered in a liquid water ocean, completely unlike anything we’ve seen before. That’s what Europa Clipper and her team are going to unveil for us.”

Scheduled for launch from the Kennedy Space Center on Oct. 10 atop a SpaceX Falcon Heavy rocket, the spacecraft will first fly past Mars in February, using the red planet’s gravity to send it toward another velocity-boosting flyby of Earth in December 2026.

Only then will the Europa Clipper be traveling fast enough to head out into deep space on a trajectory to Jupiter. Even so, the probe won’t reach its target until April 2030, using its thrusters to brake into an initial orbit around the giant planet.

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Five months later, the first in a series of close flybys of several moons will be needed to set up the first close encounter with Europa in the spring of 2031. During two science campaigns running through 2034, at least 49 close flybys of Europa are planned, including passes as low as 16 miles above the moon’s frozen surface.

The mission was progressing toward launch when engineers were alerted in May to a potentially serious problem with transistors used throughout the spacecraft. Similar components were found to fail at lower radiation doses than expected.

The radiation environment around Jupiter is powered by the planet’s titanic magnetic field, which traps and accelerates electrically charged particles from the solar wind and the volcanic moon Io. The radiation environment in the vicinity of Europa would kill an unprotected astronaut in a matter of hours.

As a result, Europa’s flight computer and other key components are protected in a radiation-resistant “vault.” Radiation “hardened” components are used throughout the spacecraft. But test data from the manufacturer showed similar components were failing at lower radiation levels than the Europa Clipper will experience.

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But after months of testing, engineers concluded the spacecraft can complete its mission with no major modifications.

“We completed extensive testing to validate the transistors on the spacecraft,” Evans said. “We ran tests 24 hours a day over the last four months at multiple locations. We simulated flight-like conditions to illuminate any issues that the transistors might have over our four-year science mission across the variety of applications we have on the spacecraft.

“We put these representative transistors into these environments, irradiated entire circuits to see how the system behaves. … We replicated that transistor self-healing, or annealing as it’s called, that occurs by heating them to room temperature while they, essentially, (are out of) that intense radiation environment as we go around each orbit.”

Based on the results, he said, “we’re ready for our final launch preparations and reviews. We are ready for Europa.”

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Ancient mummy with shrieking expression may have “died screaming from agony,” Egyptian researchers say

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Ancient mummy with shrieking expression may have "died screaming from agony," Egyptian researchers say


The mummy of an ancient Egyptian woman with her mouth wide open in what looks like an anguished shriek may have died “screaming from agony,” researchers say.

The unnamed woman mummy, discovered in a 1935 archeological expedition in Deir el-Bahari near Luxor, was kept in The Cairo Egyptian Museum and referred to as “Screaming Woman Mummy of the store of Kasr al Ainy.”

The face of the “Screaming Woman” mummy, discovered in 1935 near Luxor, is seen at the Egyptian Museum in Cairo, Egypt, January 18, 2023 in this handout photograph released on August 2, 2024.

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Sahar Saleem


In an article in the journal Frontiers in Medicine, scientists said they used CT scans and other testing to examine whether the mummy had any pathological abnormalities and assess potential causes of death.

They found that the woman, who was around 48 years old at the time she died, had lost some teeth and lived with mild arthritis of the spine. Her body was embalmed about 3,500 years ago with high quality ingredients.

Ancient Egyptians mummified bodies because they believed preserving them after death secured a worthy existence in the afterlife. Usually, internal organs would be removed during the mummification process, but that did not take place with the “Screaming Woman.”

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“In ancient Egypt, the embalmers took care of the dead body so it would look beautiful for the afterlife. That’s why they were keen to close the mouth of the dead by tying the jaw to the head to prevent the normal postmortem jaw drop,” lead researcher in the study, Cairo University radiology professor Sahar Saleem, told the Reuters news agency.

But this had not happened in the case of the “Screaming Woman.”

“This opened the way to other explanations of the widely opened mouth — that the woman died screaming from agony or pain and that the muscles of the face contracted to preserve this appearance at the time of death due to cadaveric spasm,” Saleem told Reuters, adding that, due to all of the unknowns around her history, the cause of her expression can’t be established with certainty.

Saleem told Reuters that cadaveric spasm is a poorly understood condition, where contracted muscles become rigid immediately after death.

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Fossil discovery in Greenland ice sheet reveals increased risk of sea level rise

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Fossil discovery in Greenland ice sheet reveals increased risk of sea level rise


Greenland has melted before, and as the climate warms, it will melt again — this time leading to what scientists warn could be 20 to 25 feet of sea-level rise.

During one of the warm periods within the last 1.1 million years, the center, not just the edges, of Greenland’s massive ice sheet melted away, new research has found, giving way to a dry and barren “tundra landscape” that was home to various insects and plant life. The findings were shared in a new paper published today in the Proceedings of the National Academy of Sciences

When the ice sheet initially melted, there were lower levels of greenhouse gasses in the atmosphere than there are today. Now with more carbon dioxide in the atmosphere, scientists say Greenland’s ice sheet is more susceptible to melting than previously thought. 

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“Greenland has been around for 2.7 million years with its ice,” said Paul Bierman, a scientist at the University of Vermont who co-led the new study. “Now there’s some evidence that this ice sheet is fragile.”

The researchers have been studying materials from beneath the hood of the Greenland ice sheet, the largest in the Northern hemisphere, since 2014. They examined sediment from the bottom of an ice core — dubbed GISP2 — extracted from two miles below the surface at the center of the ice sheet nearly 30 years ago. 

The 1-ounce sample of sediment was filled with clues of Greenland’s past. Tiny little black specks, when put under the microscope, revealed an insect eye, an Arctic poppy seed, parts of an Arctic willow, and tiny bits of soil fungus and spike moss — what Bierman referred to as a “frozen ecosystem underneath the ice.”

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Willow bud scale, arctic poppy seed, fungal bodies, and rock spike moss megaspores found in the GISP2 soil sample viewed under a microscope.

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Halley Mastro


According to researchers, the fossils provide “direct confirmation” that 90% of the ice sheet was once gone.

“Finding these fossils in the center of the ice sheet is unambiguous evidence that Greenland’s ice has disappeared [in the past],” said Bierman. “And once you lose the center of the ice sheet, you’ve lost it all.”

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The findings supports what’s called the “fragile Greenland” hypothesis: that nature, outside of human influence, has caused the ice sheet to melt at least once since it formed, Bierman said. 

At 656,000 square miles, the Greenland ice sheet currently covers around 80% of the island territory. To put that into perspective, it’s about three times the size of Texas.

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Drill dome and camp for GISP2, in Summit Greenland.

Christine Massey

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NASA, which has mapped Greenland’s ice loss, says the sheet has “rapidly declined in the last several years,” prompting the global sea level to rise around 0.03 inches per year. Greenland’s melting ice mass is now the No. 1 driver of sea level rise,  according to Bierman.

“In the early years of the climate warming, it was mountain glaciers that were doing most of the melting and adding water to the ocean,” he said. “Now it’s Greenland.”

While it could be a few thousand years before the entire Greenland mass melts, Bierman said, the consequences would be dire: hundreds of millions of people could lose their homes and businesses. Places we hold near and dear to our hearts would be lost.

“As I like to say when people ask me, why does it matter? I say think about your favorite beach. And then imagine your favorite beach with 25 feet of water on it,” Bierman said.

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Discovery of “hobbit” fossils suggests tiny humans roamed Indonesian islands 700,000 years ago

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Discovery of "hobbit" fossils suggests tiny humans roamed Indonesian islands 700,000 years ago


Twenty years ago on an Indonesian island, scientists discovered fossils of an early human species that stood at about 3 1/2 feet tall, earning them the nickname “hobbits.”

Now a new study suggests ancestors of the hobbits were even slightly shorter.

“We did not expect that we would find smaller individuals from such an old site,” said Yousuke Kaifu, co-author of the study, which was published on Tuesday in the journal Nature. 

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The original hobbit fossils date back to between 60,000 and 100,000 years ago. The new fossils were excavated at a site called Mata Menge, about 45 miles from the cave where the first hobbit remains were uncovered. The fossils were found on the top of a ribbon-shaped, pebbly sandstone layer in a small stream. They included exceptionally small teeth that possibly came from two individuals, researchers said. 

Hobbit Fossils
This image provided by Yousuke Kaifu shows an excavated arm bone fragment, left, next to the upper arm bone of an original “hobbit” that lived on the Indonesian island of Flores.

Yousuke Kaifu / AP


In 2016, researchers suspected the earlier relatives could be shorter than the hobbits after studying a jawbone and teeth collected from the new site. Further analysis of a tiny arm bone fragment and teeth suggests the ancestors were a mere 2.4 inches shorter and existed 700,000 years ago.

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“They’ve convincingly shown that these were very small individuals,” said Dean Falk, an evolutionary anthropologist at Florida State University who was not involved with the research.

Researchers have debated how the hobbits — named Homo floresiensis after the remote Indonesian island of Flores — evolved to be so small and where they fall in the human evolutionary story. They’re thought to be among the last early human species to go extinct.

Hobbit Fossils
This photo provided by Gerrit van den Bergh shows the Mata Menge excavation site on the Indonesian island of Flores on Oct. 15, 2014.

Gerrit van den Bergh / AP

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Scientists don’t yet know whether the hobbits shrank from an earlier, taller human species called Homo erectus that lived in the area, or from an even more primitive human predecessor. More research — and fossils — are needed to pin down the hobbits’ place in human evolution, said Matt Tocheri, an anthropologist at Canada’s Lakehead University.

“This question remains unanswered and will continue to be a focus of research for some time to come,” Tocheri, who was not involved with the research, said in an email.



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NASA outlines backup plan to get Starliner crew back to Earth from International Space Station if Boeing ship can’t bring them home

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NASA outlines backup plan to get Starliner crew back to Earth from International Space Station if Boeing ship can't bring them home


As NASA debates the safety of Boeing’s Starliner spacecraft in the wake of multiple helium leaks and thruster issues, the agency is “getting more serious” about a backup plan to bring the ship’s two crew members back to Earth aboard a SpaceX Crew Dragon, officials said Wednesday.

In that case — and no final decisions have been made — Starliner commander Barry “Butch” Wilmore and co-pilot Sunita Williams would remain aboard the International Space Station for another six months and come down on a Crew Dragon that’s scheduled for launch Sept. 24 to carry long-duration crew members to the outpost.

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Boeing’s Starliner spacecraft docked to the forward port of the International Space Station as the lab complex approached Egypt and the Nile delta.

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NASA


Two of the four “Crew 9” astronauts already assigned to the Crew Dragon flight would be bumped from the mission and the ship would be launched with two empty seats. Wilmore and Williams then would return to Earth next February with the two Crew 9 astronauts.

Shortly before the Crew Dragon launch, the Starliner would undock from the station’s forward port and return to Earth under computer control, without any astronauts aboard. The Crew Dragon then would dock at the vacated forward port.

Two earlier Starliner test flights were flown without crews and both landed successfully. The current Starliner’s computer system would need to be updated with fresh data files, and flight controllers would need to brush up on the procedures, but that work can be done in time to support a mid September return.

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If that scenario plays out, Wilmore and Williams would end up spending 268 days — 8.8 months — in space instead of the week or so they planned when they blasted off atop a United Launch Alliance Atlas 5 rocket on June 5.

Based on uncertainty about the precise cause of the thruster problems, “I would say that our chances of an uncrewed Starliner return have increased a little bit based on where things have gone over the last week or two,” said Ken Bowersox, NASA’s director of space operations.

“That’s why we’re looking more closely at that option to make sure that we can handle it.”

But he cautioned that no final decisions will be made on when — or how — to bring the Starliner crew home until the agency completes a top-level flight readiness review.

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No date has been set, but it could happen by late next week or the week after.

“Our prime option is to return Butch and Suni on Starliner,” said Steve Stich, manager of NASA’s Commercial Crew Program. “However, we have done the requisite planning to make sure we have other options open. We have been working with SpaceX to ensure that they’re ready to (return) Butch and Suni on Crew 9 if we need that.

“Now, we haven’t approved this plan (yet). We’ve done all the work to make sure this plan is there … but we have not turned that on formally. We wanted to make sure we had all that flexibility in place.”

Before the Starliner was launched, NASA and Boeing engineers knew about a small helium leak in the spacecraft’s propulsion system. After ground tests and analysis, the team concluded the ship could be safely launched as is.

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Starliner co-pilot Suni Williams, left, and commander Barry “Butch” Wilmore, seen during a space-to-ground news conference last month. The two astronauts are now 63 days into a missions originally expected to last a little more than one week.

NASA


The day after launch, however, four more helium leaks developed and five aft-facing maneuvering thrusters failed to operate as expected. Ever since, NASA and Boeing have been carrying out data reviews and ground tests in an effort to understand exactly what caused both issues.

The Starliner uses pressurized helium to push propellants to the thrusters, which are critical to keeping the spacecraft properly oriented. That’s especially important during the de-orbit braking “burn” using larger rocket engines to slow the ship down for re-entry and an on-target landing.

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To clear the Starliner for a piloted return to Earth, engineers must develop acceptable “flight rationale” based on test data and analyses that provides confidence the ship can make it through re-entry and landing with the required level of safety.

“The Boeing team (is) very confident that the vehicle could bring the crew home right now with the uncertainty we’ve got,” said Bowersox. “But we’ve got other folks that are probably a little more conservative. They’re worried that we don’t know for sure, so they estimate the risk higher and they would recommend that that we avoid coming home (on Starliner) because we have another option.

“So that’s a part of the discussion that we’re having right now. But again, I think both views are reasonable with the uncertainty band that we’ve got, and so our effort is trying to reduce that uncertainty.”

Boeing adamantly argues the Crew Dragon backup plan isn’t needed and that tests and analyses of helium leaks in the Starliner’s propulsion system and initial trouble with maneuvering thrusters show the spacecraft has more than enough margin to bring Wilmore and Williams safely back to Earth.

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The helium leaks are understood, Boeing says, they have not gotten worse and more than enough of the pressurized gas is on board to push propellants to the thrusters needed to maneuver and stabilize the spacecraft through the critical de-orbit braking burn to drop out of orbit for re-entry and landing.

Likewise, engineers believe they now understand what caused a handful of aft-facing maneuvering jets to overheat and fire at lower-than-expected thrust during rendezvous with the space station, causing the Starliner’s flight computer to shut them down during approach.

Ground tests of a new Starliner thruster, fired hundreds of times under conditions that mimicked what those aboard the spacecraft experienced, replicated the overheating signature, which was likely caused by multiple firings during tests of the capsule’s manual control system during extended exposure to direct sunlight.

The higher-than-expected heating likely caused small seals in thruster valve “poppets” to deform and expand, the analysis indicates, which reduced the flow of propellant. The thrusters aboard the Starliner were test fired in space under more normal conditions and all operated properly, indicating the seals had returned to a less intrusive shape.

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New procedures are in place to prevent the overheating that occurred during the rendezvous. Additional manual test firings have been ruled out, no extended exposure to the sun is planned and less frequent firings are required for station departure compared to rendezvous.

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The Starliner capsule in Boeing’s processing facility at the Kennedy Space Center. The Service Module is the white lower section housing critical helium propellant pressurization tanks and plumbing along with maneuvering thrusters in four rectangular engine pods, or “doghouses,” spaced around the exterior.

William Harwood/CBS News


In a statement Wednesday, Boeing said, “We still believe in Starliner’s capability and its flight rationale. If NASA decides to change the mission, we will take the actions necessary to configure Starliner for an uncrewed return.”

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The helium plumbing and thrusters are housed in the Starliner’s service module, which will be jettisoned to burn up in the atmosphere before the crew capsule re-enters for landing. As such, engineers will never be able to examine the hardware first hand to prove, with certainty, what went wrong.

At this point, that uncertainty appears to support bringing Wilmore and Williams back to Earth aboard the Crew Dragon. But it’s not yet a certainty.

“If we could replicate the physics in some offline testing to understand why this poppet is heating up and extruding and then why it’s contracting, that would give us additional confidence to move forward, to return Butch and Sonny on this vehicle,” Stich said.

“That’s what the team is really striving to do, to try to look at all the data and see if we can get a good physical explanation of what’s happening.”

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In the meantime, the wait for a decision, one way or the other, drags on.

“In the end, somebody – some one person – designated to be the decision maker, that person has to come to a conclusion,” Wayne Hale, a former shuttle flight director and program manager, wrote in a blog post earlier this week.

“The engineers will always always always ask for more tests, more analysis, more time to get more information to be more certain of their conclusions. The decider also has to decide when enough has been done. The rub in all of this … is that it always involves the risk to human life.”

Hale concluded his post by saying: “I do not envy today’s decision makers, the ones weighing flight rationale. My only advice is to listen thoroughly, question effectively, ask for more data when necessary. But when it is time, a decision must be made.”

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Drones setting a new standard in ocean rescue technology

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Drones setting a new standard in ocean rescue technology


Last month, two young paddleboarders found themselves stranded in the ocean, pushed 2,000 feet from the shore by strong winds and currents. Thanks to the deployment of a drone, rescuers kept an eye on them the whole time and safely brought them aboard a rescue boat within minutes.

In North Carolina, the Oak Island Fire Department is one of a few in the country using drone technology for ocean rescues. Firefighter-turned-drone pilot Sean Barry explained the drone’s capabilities as it was demonstrated on a windy day. 

“This drone is capable of flying in all types of weather and environments,” Barry said. 

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Equipped with a camera that can switch between modes — including infrared to spot people in distress — responders can communicate instructions through a speaker. It also can carry life-preserving equipment.

The device is activated by a CO2 cartridge when it comes in contact with water. Once triggered, it inflates into a long tube, approximately 26 inches long, providing distressed swimmers something to hold on to.

In a real-life rescue, after a 911 call from shore, the drone spotted a swimmer in distress. It released two floating tubes, providing the swimmer with buoyancy until help arrived.

Like many coastal communities, Oak Island’s population can swell from about 10,000 to 50,000 during the summer tourist season. Riptides, which are hard to detect on the surface, can happen at any time.

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Every year, about 100 people die due to rip currents on U.S. beaches. More than 80% of beach rescues involve rip currents, if you’re caught in one, rescuers advise to not panic or try to fight it, but try to float or swim parallel to the coastline to get out of the current.

Oak Island Fire Chief Lee Price noted that many people underestimate the force of rip currents.

“People are, ‘Oh, I’m a good swimmer. I’m gonna go out there,’ and then they get in trouble,” Price said.

For Price, the benefit of drones isn’t just faster response times but also keeping rescuers safe. Through the camera and speaker, they can determine if someone isn’t in distress.

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Price said many people might not be aware of it. 

“It’s like anything as technology advances, it takes a little bit for everybody to catch up and get used to it,” said Price.

In a demonstration, Barry showed how the drone can bring a safety rope to a swimmer while rescuers prepare to pull the swimmer to shore.

“The speed and accuracy that this gives you … rapid deployment, speed, accuracy, and safety overall,” Price said. “Not just safety for the victim, but safety for our responders.”

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Horseshoe crabs: Ancient creatures who are a medical marvel

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Horseshoe crabs: Ancient creatures who are a medical marvel


Horseshoe crabs: Ancient creatures who are a medical marvel – CBS News

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Correspondent Conor Knighton visits New Jersey beaches along the Delaware Bay to learn about horseshoe crabs – mysterious creatures that predate dinosaurs – whose very blood has proved vital to keeping humans healthy by helping detect bacterial endotoxins. He talks with environmentalists about the decline in the horseshoe crab population, and with researchers who are pushing the pharmaceutical industry to switch its use of horseshoe crab blood with a synthetic alternative used in medical testing.

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