What Actually Happens During a Total Lunar Eclipse?

A lunar eclipse occurs when the Earth moves precisely between the Sun and the Moon. While you might expect the Moon to disappear completely as it slips into Earth’s shadow, something far more beautiful happens: the Moon glows a deep red or orange, often called a “blood moon”.

This isn’t a rare magic trick. Lunar eclipses are a regular part of skywatching, but total eclipses—where the whole Moon is covered—are less common, occurring only a couple of times each year. The eclipse on September 7, 2025, is particularly notable for its long totality of 82 minutes and global visibility.

Why Does the Moon Look Red Instead of Black?

You’d think that when Earth blocks the Sun, the Moon would go entirely dark. Instead, it glows a haunting, coppery red. The explanation is pure science and a little bit of planetary teamwork.

Earth’s Atmosphere Is the Secret Ingredient

As the Moon passes through the darkest part of Earth’s shadow—called the umbra—the only sunlight that reaches the Moon has traveled through Earth’s atmosphere first. This journey bends and filters the light, removing the shorter blue wavelengths and letting through the longer red and orange wavelengths.

In other words, sunlight passes through a “ring” of Earth’s air. The bluer, shorter rays scatter (the same phenomenon that colors our daytime sky blue and sunsets orange/red), whereas the redder rays bend around the globe and spill onto the Moon’s surface. That’s why people all over the world see the Moon glowing red during the eclipse—it’s lit by every sunrise and sunset on Earth, all at once.

The Science: Rayleigh Scattering and Blood Moons

This filtering process is known as Rayleigh scattering—the same effect that gives us blue skies and those stunning red sunsets. When the Moon is inside the umbra, it catches sunlight that’s been bent through mammoth slabs of our planet’s air, with all the blue stripped out and only red and orange left to paint the lunar surface.

The term “blood moon” is popular, but not scientific. It’s just a poetic way of describing the result of this beautiful atmospheric chemistry.

Why the Color Varies Each Eclipse

Not every lunar eclipse looks the same. Sometimes the Moon shows a brighter orange; other times, it’s a dark rusty red. Volcanoes, wildfires, dust storms, and even local weather can all affect the clarity and color of the Earth’s shadow. For example, after a major volcanic eruption, there’s so much dust in the air that the Moon can appear an eerie, deep red or even brown.

A Universal Story in the Night Sky

One of the coolest things about a lunar eclipse is that it’s safe to watch with the naked eye—no fancy glasses needed! The next time you see the Moon turning red, remember: you’re looking at sunlight that’s passed through every sunrise and sunset on the planet, refracted and projected 380,000 km onto the Moon’s surface.

Fun Fact: If you were standing on the Moon during the eclipse, you’d see a ring of red light outlining Earth—a sight of all the sunsets and sunrises happening at that moment.

This past week, Himachal Pradesh has declared its entire territory a ‘disaster-affected zone’ under the National Disaster Management Act, following unprecedented monsoon devastation across the state. The numbers behind this unprecedented decision are sobering: over 320 people dead, 1,337 roads blocked, and economic losses exceeding Rs 3,000 crores since June.

But here’s what the headlines aren’t telling you: this isn’t just about heavy rain. It’s about how climate change is rewiring one of the world’s most fragile mountain ecosystems, creating a perfect storm of geological instability, extreme weather, and human vulnerability.

The Scale of Devastation: By the Numbers

Let’s start with what’s happening right now. Since June 20, Himachal has been pummeled by what meteorologists are calling “extremely abnormal” weather patterns:

• 320+ deaths from landslides, flash floods, and weather-related accidents
• 1,280+ houses destroyed, with thousands more damaged
• 35,240 animals killed in the disasters
• Four national highways completely blocked
• 16 pilgrims died during the Manimahesh Yatra alone

The India Meteorological Department issued red alerts through September 2nd, predicting more “extremely heavy rainfall” of 200mm+ in single days. To put that in perspective, that’s more rain than many regions see in entire months.

The Science Behind the Chaos

What makes this particularly alarming isn’t just the intensity—it’s the pattern. Down to Earth magazine’s analysis shows the Himalayan region has experienced at least one disaster daily between January and August 2025. That’s not weather; that’s a fundamental shift in how this ecosystem functions.

Dr. Navin Juyal, a geologist who’s studied Himalayan flooding patterns for decades, explains what’s actually happening: “Climate change allows each kilogram of air to hold more moisture, so storms unload precipitation more intensely and erratically. In steep vertical valleys, even modest amounts of water can set deep moraines and loose slopes in motion”.

Here’s the key insight: the Himalayas are warming faster than the global average, creating what scientists call “atmospheric rivers”—narrow corridors of concentrated water vapor that can dump enormous amounts of precipitation in very short periods.

The Geological Time Bomb

But the weather is only half the story. The real danger lies in what’s happening beneath our feet.

Geologist S.P. Sati describes the mechanism: “In such steep, narrow valleys, a landslide at one point triggers similar processes in other glacial branches in rapid succession, resulting in multiple floods”.

Translation: the Himalayas are essentially a geological house of cards. When one slope fails, it creates a domino effect that can devastate entire river valleys.

The numbers are stark:

• 50% of natural springs across the Indian Himalayan Region are drying up
• Himalayan glaciers are retreating rapidly, increasing flood risks
• 1,072 sq km of forest cover lost between 2019-2021 in Himalayan states
• 110 glaciers lost in Arunachal Pradesh alone over 32 years

Human Choices, Natural Consequences

Here’s where the story gets complicated. While climate change is loading the dice, human decisions are determining how catastrophic the results become.

Take Dharali village in Uttarakhand, which was devastated by flash floods in early August. Satellite images show the entire market was built on what geomorphologists call a “debris-flow fan”—essentially, land formed by centuries of flood deposits.

“Establishing a settlement on land where the river continually deposits sediments is precarious,” says Wolfgang Schwanghart, a geomorphologist at the University of Potsdam who studies Himalayan disasters.

The pattern repeats across the region: construction on riverbeds, unauthorized buildings in landslide-prone areas, and infrastructure projects that alter natural drainage patterns without proper geological assessment.

The Broader Himalayan Crisis

Himachal’s disaster declaration comes as the entire Himalayan arc faces similar pressures. The region supports over 50 million people directly and provides water security for 600+ million through major river systems.

Key vulnerabilities by region:

• Ladakh: Glacier retreat and permafrost thaw
• Jammu & Kashmir: Frequent landslides along defense highways
• Uttarakhand: Erratic rainfall worsened by tourism pressure
• Sikkim: Transboundary glacial floods
• Arunachal Pradesh: Sudden river floods with inadequate warning systems

The 15th Finance Commission allocated Rs 1.6 lakh crore for climate resilience, but experts worry it’s not enough.

What This Means for the Future

Climate scientists are clear: this is the new normal, not an exception. Ashutosh Kumar from IIT Mandi explains: “Shorter, erratic bursts of weather—brief dry spells followed by intense moisture—mean slopes never fully dry out and therefore remain persistently weakened”.

The immediate priorities, according to experts:

1. Moratorium on large projects in fragile zones until proper geological studies
2. Real-time monitoring systems for dams, glacial lakes, and unstable slopes
3. Community-specific early warning systems
4. Dignified relocation for people in high-risk areas

The Uncomfortable Truth

Environmental campaigner Hemant Dhyani puts it bluntly: “The Himalayas must no longer be viewed as a source of revenue. You cannot justify destroying this natural treasure for short-term gains”.

But here’s the challenge: the same development projects causing geological instability are also providing jobs and economic opportunities for mountain communities. Finding sustainable alternatives isn’t just an environmental imperative—it’s an economic necessity.

Beyond Disaster Management

What’s happening in Himachal isn’t just a state emergency; it’s a preview of climate adaptation challenges across mountain regions worldwide. The solutions require thinking beyond traditional disaster response to fundamentally rethinking how humans live in rapidly changing mountain environments.

The science is clear: more intense rainfall, more unstable slopes, and more frequent disasters are now built into the Himalayan climate system. The question isn’t whether similar disasters will happen again—it’s whether we’ll learn to work with these new realities instead of being repeatedly surprised by them.

As one Dharali resident told rescuers: “We urged the administration to halt construction near the river, but nothing was done.” Now entire markets lie buried under 12 meters of debris.

The mountains are sending us a message. The question is whether we’re finally ready to listen.

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What are your thoughts on balancing development needs with environmental protection in fragile mountain ecosystems? Have you experienced similar weather changes in your region?

In a groundbreaking achievement, scientists have launched the world’s first wooden satellite into space to explore the material’s suitability for orbit. Named LignoSat, derived from the Latin for “wood,” the satellite was sent into space on a SpaceX mission to the International Space Station (ISS) on Monday. It will later be deployed into orbit, where researchers will observe how the wood withstands the extreme conditions of space over a period of six months.

The initiative, a collaboration between Kyoto University and Sumitomo Forestry, began in 2020. In 2022, they conducted exposure tests aboard the ISS for over 240 days, ultimately selecting Hoonoki, a type of Magnolia wood known for its strength, stability, and workability. This wood is traditionally used in Japan for crafting sword sheaths due to its shatter-resistant properties, according to Reuters.

Since space is devoid of water and oxygen, the wood is shielded from fire and decay, Kyoto University scientists explain. Additionally, they will evaluate the wood’s potential to protect semiconductors from space radiation, Reuters reports.

Scientists in Japan are set to test the world’s first wooden satellite, LignoSat, developed by a team from Kyoto University and homebuilder Sumitomo Forestry, and will be launched on Nov. 5' pic.twitter.com/Go6sSnPXP0

— Reuters Science News (@ReutersScience) November 1, 2024

“If our wooden satellite succeeds, we plan to propose it to Elon Musk’s SpaceX,” said Takao Doi, an astronaut and professor at Kyoto University. The team envisions that wooden satellites could reduce space pollution, as they would not emit aluminum oxide when burning up upon re-entry, unlike traditional metal satellites. Over the next 50 years, Doi’s team envisions growing wood for timber-based habitats on the Moon and Mars. “With timber, a material we can cultivate ourselves, we could construct homes and sustain life in space indefinitely,” Doi told Reuters.