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Four thousand years ago, the woolly mammoth, a prominent figure of the Ice Age, met its end on Wrangel Island, located off the coast of modern-day Siberia. Historically, scientists speculated that the isolation of this final mammoth population led to genetic inbreeding, contributing to their extinction. However, new research offers a different perspective, suggesting that inbreeding was not the sole factor in their demise.

Inbreeding and Genetic Health

A recent study, published in Cell on July 11, 2024, challenges the notion that genetic isolation was the primary cause of the woolly mammoths’ extinction. The research, led by Dr Love Dalén, an evolutionary geneticist at the Centre for Palaeogenetics in Stockholm, examined 21 complete genomes from mammoths that lived during their final 50,000 years. Contrary to earlier beliefs, the study found that while the Wrangel Island mammoths were inbred, this alone did not lead to their extinction.

Dr Dalén’s team discovered that over time, the mammoth herd on Wrangel Island lost many of its harmful genetic mutations. This indicates that inbreeding might have led to the elimination of detrimental mutations rather than exacerbating them. The Wrangel Island herd, which began with a small population of around eight individuals, eventually grew to between 200 and 300 members and maintained this size until the species’ extinction.

Challenging the Meltdown Model

The findings of the study offer significant evidence against the “meltdown model,” which suggests that genetic isolation and inbreeding lead to a gradual accumulation of harmful mutations, eventually causing extinction. Instead, the research indicates that the mammoths may have experienced an improvement in their genetic health over time, contradicting the idea that inbreeding alone was a death sentence for the species.

Vincent Lynch, an evolutionary biologist at the University at Buffalo, notes that while the study provides strong evidence against the meltdown model, it does not entirely exclude it. He suggests that a reduced genetic variation might have made the mammoths more vulnerable to other threats, such as diseases, climatic changes, or human encroachment.

Unresolved Mysteries

Despite these revelations, the exact reasons behind the woolly mammoths’ final extinction remain uncertain. Dr Dalén proposes that unforeseen disasters or significant environmental shifts could have played a crucial role in their demise. Without such catastrophic events, it is possible that the mammoths could have continued to survive.

The study underscores the complexity of extinction events and highlights the need for ongoing research to fully understand the diverse factors that contribute to the disappearance of species. While the genetic health of the Wrangel Island mammoths seems to have improved, other factors likely played a significant role in their ultimate extinction.

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SpaceX Successfully Launches 23 Starlink Satellites on Brand-New Falcon 9 Rocket

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SpaceX Successfully Launches 23 Starlink Satellites on Brand-New Falcon 9 Rocket

SpaceX marked its 60th Falcon 9 flight of 2025 by successfully launching a brand-new Falcon 9 booster rocket on the 20th of May. This rocket carries 23 Starlink V2 Mini satellites into low Earth orbit. Among those, 13 feature Direct to Cell capabilities. Originally, it was targeting 11:58 p.m. EDT on May 19 (0358 UTC on May 20) for the launch, but that try was aborted just before liftoff, for reasons that the company did not immediately explain. It was finally launched on Tuesday (May 20) at 11:19 p.m. EDT (0319 GMT on May 21) from the Space Launch Complex 40 at Cape Canaveral Space Force Station in Florida.

About the launch

According to SpaceX’s mission overview, this was the first-ever launch for this particular Falcon 9’s (booster B1095) first stage. While most recent SpaceX missions have reused Falcon 9 boosters , a signature part of the company’s cost-saving and sustainability strategy ,Tuesday’s flight featured a rare first-stage debut.

The rocket successfully completed its initial mission, separating from the upper stage around two and a half minutes after liftoff. About eight minutes later, the booster made a precise landing on the SpaceX drone ship “Just Read the Instructions,” stationed in the Atlantic Ocean. This smooth recovery sets the stage for future reusability of the rocket.

Technical Advancement

Of the 23 satellites onboard, 13 were outfitted with direct-to-cell technology — a feature designed to enable satellite connectivity directly to mobile phones, especially in areas lacking terrestrial infrastructure. After reaching space, the rocket’s second stage performed a short engine burn to circularize the orbit before deploying the satellites about 65 minutes after launch.

Starlink is the largest satellite megaconstellation ever constructed, consisting of about 7,500 operational satellites at the moment. And that number is growing all the time, as Tuesday’s action shows.

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Polaris Wasn’t Always the North Star: How Earth’s Wobble Shifts the Celestial Pole

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Polaris Wasn’t Always the North Star: How Earth’s Wobble Shifts the Celestial Pole

Polaris has been the constant guide for explorers and navigators in the northern hemisphere for thousands of years, hence its other name, the famous North Star. It is significant where it is located near the north rotational axis of Earth, and the whole sky appears to spin about it. But that’s not always been the case, and it won’t always be the case. The planet’s sluggish axial wobble, called precession, makes the pole trace a circle about every 26,000 years, bringing different stars into view over the ages.

How Earth’s 26,000-Year Axial Precession Shifts the North Star Over Time

As per NASA, gravitational forces from the sun and moon affect the rotation of Earth; these produce a bulge at the equator and axial precession. Every 26,000 years or so, this wobble makes a complete circle, and it makes the celestial pole move on a cycle, pointing to stars in sequence over time. Thuban, in the star constellation Draco, was the closest visible in the sky to the celestial pole some 4,700 years ago. The stars, such as Kochab and Pherkad, were the nearest to the pole about 3,000 years ago. Polaris now has the title, but not for very long.

The axis of the Earth will eventually change again, bringing new stars into prominence. In about 2,200 years, Errai in the constellation Cepheus will become the North Star. Alderamin, likewise in Cepheus, will have its turn some 5,000 years from now. Deneb, who will approach the pole once more about 9,800 CE, and Vega, a former pole star, returning in roughly 12,000 years, complete this cycle.
Many of these stars fit identifiable constellations, including Cepheus, Draco, and Ursa Minor. Modern stargazing apps incorporating augmented reality for nighttime sky navigation allow amateur astronomers to trace their positions.

As Polaris continues to shine overhead today, its reign is only temporary. Earth’s steady 26,000-year precessional cycle guarantees that other stars will eventually take its place, proving that even in the cosmos, change is constant.

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Scientists Warn of Inadequate Solar Storm Forecasting: What You Need to Know

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Scientists Warn of Inadequate Solar Storm Forecasting: What You Need to Know

Imagine being told a storm is approaching, but you won’t know how dangerous it truly is until minutes before impact. That’s the reality scientists face with solar storms. Although scientists have improved our ability to monitor coronal mass ejections (CMEs) from the Sun and project their arrival at Earth, the most important consideration — the orientation of the storm’s magnetic field — remains unknown until the very last minute. This direction, referred to as the Bz component, decides whether the CME will pass by with little influence or cause disturbances to satellites, electricity grids, and GPS systems.

Lack of Early Bz Data Leaves Earth Vulnerable to Solar Storms, Scientists Urge Wider Sun Coverage

As per a report on Space.com, solar physicist Valentín Martínez Pillet emphasised that knowing the Bz value earlier could dramatically improve our ability to prepare. Currently, spacecraft like NASA’s ACE and DSCOVR detect Bz only when the CME reaches Lagrange Point 1 (L1), giving us just 15 to 60 minutes’ warning. Martínez Pillet predicts it could take 50 years to achieve the forecasting precision we have for Earth’s weather unless we expand our view of the Sun with new satellites placed at Lagrange points L4, L5, and L3.

Despite having the scientific models needed, Martínez Pillet argues we lack vital real-time data from different solar perspectives. Most observations currently come from a single vantage point — L1, which limits our predictive ability. Missions like ESA’s upcoming Vigil, scheduled for launch in 2031 to L5, aim to fill this gap by detecting the CME’s shape and magnetic orientation from the side, potentially giving up to a week’s notice.

But decades may be too long to wait. History reminds us of the danger: the 1859 Carrington Event caused telegraph failures, and a near miss in 2012 could have caused trillions in damage if it had struck Earth. In a 2013 paper, Dan Baker of LASP warned that a direct hit would have left the modern world technologically crippled.

Today, tools like the Global Oscillation Network Group (GONG) and DSCOVR offer continuous solar monitoring, but their limitations emphasise the need to provide broader coverage. “The Sun isn’t changing,” Martínez Pillet said. “It’s our dependence on technology that’s made us more vulnerable.” Until we build the infrastructure to see solar storms before they hit, we may remain dangerously exposed.

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