Have you ever looked up at the night sky and noticed a faint glow, gracefully extending from the horizon in a triangular shape? This enchanting phenomenon is known as zodiacal light, often referred to as “false dawn” when it’s visible just before sunrise. While it may seem like a mere trick of the light, the zodiacal light holds a fascinating story about the universe surrounding our planet.

The Science Behind Zodiacal Light

Zodiacal light is the result of sunlight scattering off interplanetary dust, creating a delicate illumination in the night sky. This dust resides in a thick, pancake-shaped cloud known as the zodiacal cloud, which orbits in the ecliptic plane of our Solar System. Ranging from 10 to 300 micrometers in size, these tiny particles have masses that can span from one nanogram to several micrograms. Together, they contribute to what we see as a soft glow, complementing the natural light of a moonless night.

Interestingly, zodiacal light can be seen most effectively in dark locations, far away from the interference of city lights or moonlight. When conditions are perfect—a clear night with minimal light pollution—this soft glow stretches from the direction of the Sun, gracefully illuminating the darker parts of the sky. It’s most prominent in the western sky during spring after sunset and in the eastern sky during autumn before dawn.

The Origins of Cosmic Dust

The source of the dust that creates zodiacal light has long been a subject of exploration and debate. Initially thought to originate from active comet tails or collisions among asteroids, recent research suggests that a significant portion of the dust comes from the gradual fragmentation of dormant comets, specifically those in the Jupiter-family category.

When comets break apart, they send tiny fragments scattering through space. As these particles eventually disintegrate further due to collisions and space weathering, they continue to replenish the zodiacal dust cloud. This dynamic relationship ensures that our view of zodiacal light is not just a fleeting moment, but a persistent feature of our cosmic environment.

Viewing Zodiacal Light: Tips and Tricks

To catch a glimpse of this celestial beauty, timing and location are crucial. For those in mid-latitude regions, the ideal times to observe zodiacal light are during the evenings in spring and mornings in autumn. Choose a spot far from city lights, under a clear and moonless sky. As twilight fades, lean back, breathe in the fresh evening air, and let your eyes adjust to the darkness.

The sight will often reveal a column of light that appears brighter near the horizon and tilts at an angle parallel to the ecliptic. Often mistaken for a glimpse of the Milky Way, zodiacal light offers a serene reminder of the intricate cosmos we inhabit.

The Connection to Gegenschein

Zodiacal light isn’t the only celestial phenomenon related to interplanetary dust. There’s also the gegenschein, or “counterglow,” which is a faint oval glow seen directly opposite the Sun. This unique aspect of zodiacal light and gegenschein adds depth to our understanding of celestial phenomena and invites us to ponder our place in the universe.

Advertisement

A Cosmic Invitation

Zodiacal light is not just a backdrop for the stars; it represents a beautiful, cosmic connection between our planet and the infinity beyond. It serves as a gentle reminder of the fleeting moments in nature—moments that encourage us to pause, look up, and marvel at the intricate dance of light and dust that swirls around us.

So next time you find yourself under a dark sky, take a moment to seek out this enchanting glow. The zodiacal light is waiting, inviting you to experience the magic of our universe. Happy stargazing!

For more information visit these links:

Wikipedia: https://en.wikipedia.org/wiki/Zodiacal_light

Earth-Sky: https://earthsky.org/astronomy-essentials/zodiacal-light-false-dusk-how-to-see-explanation/

The science section of our news blog STM Daily News provides readers with captivating and up-to-date information on the latest scientific discoveries, breakthroughs, and innovations across various fields. We offer engaging and accessible content, ensuring that readers with different levels of scientific knowledge can stay informed. Whether it’s exploring advancements in medicine, astronomy, technology, or environmental sciences, our science section strives to shed light on the intriguing world of scientific exploration and its profound impact on our daily lives. From thought-provoking articles to informative interviews with experts in the field, STM Daily News Science offers a harmonious blend of factual reporting, analysis, and exploration, making it a go-to source for science enthusiasts and curious minds alike. https://stmdailynews.com/category/science/

Advertisement

Planetary Parade

Astronomy enthusiasts and casual stargazers alike have something extraordinary to look forward to at the end of February. For one brief moment, on the evening of February 28, 2025, all seven planets—Mars, Jupiter, Uranus, Venus, Neptune, Mercury, and Saturn—will align in the night sky, creating a captivating planetary parade. This remarkable event marks the last time such an alignment will be visible until 2040, making it an occasion not to be missed.

What to Expect

The planetary parade will unfold shortly after sunset, with each planet showcasing its brilliance against the backdrop of the evening sky. While most of these celestial bodies will shine brighter than even the brightest stars, Uranus and Neptune will likely require binoculars or a telescope for a better view.

Currently, six of the planets are already aligned, but stargazers will have to wait until February 28 for Mercury to make its debut just above the horizon. Dr. Christopher Barnes, a senior lecturer at the University of Derby, explains the visibility details: “Mars will appear in the east, Jupiter and Uranus in the southeast, and Venus, Neptune, and Saturn in the west.”

Viewing Tips

For those wishing to experience this cosmic event, the best time to observe will be just after sunset when the stars begin to appear. Dr. Barnes suggests that even people in urban areas, where light pollution is often an issue, will be able to see most of the planets. However, seeking a location away from city lights will enhance the viewing experience.

The Benefits of Stargazing

Beyond the thrilling visual spectacle, taking time to gaze upon the stars and planets offers numerous benefits for one’s mental and emotional well-being. Dr. Barnes points out that stargazing encourages mindfulness, allowing individuals to detach from the stresses of daily life. “Engaging with the night sky fosters a sense of peace, restoration, and perspective,” he says.

Future Events

After February 28, the next opportunity to see a planetary alignment of five or more planets will occur in late October 2028 and again in February 2034. However, another seven-planet alignment will not be witnessed for another 15 years, making this February a particularly special occasion.

To cater to those unable to view the parade due to unfavorable weather or light pollution, several observatories will provide live streams of the event. This means everyone can partake in this astral celebration from the comfort of their homes.

As we approach February 28, it’s time to mark your calendars for this rare planetary parade. Whether you grab your telescope, plan a trip to a dark-sky location, or tune in to a live stream, don’t miss your chance to witness this extraordinary alignment of the planets, a spectacle that will be remembered long after it fades from view. Prepare to look up and enjoy the wonders of our solar system!

Advertisement

Resources:

Who doesn’t love a parade, especially a planet parade? How and when to see up to 7 planets

Planetary Parade will soon be visible in the evening sky

The science section of our news blog STM Daily News provides readers with captivating and up-to-date information on the latest scientific discoveries, breakthroughs, and innovations across various fields. We offer engaging and accessible content, ensuring that readers with different levels of scientific knowledge can stay informed. Whether it’s exploring advancements in medicine, astronomy, technology, or environmental sciences, our science section strives to shed light on the intriguing world of scientific exploration and its profound impact on our daily lives. From thought-provoking articles to informative interviews with experts in the field, STM Daily News Science offers a harmonious blend of factual reporting, analysis, and exploration, making it a go-to source for science enthusiasts and curious minds alike. https://stmdailynews.com/category/science/

Timothy J McCoy, Smithsonian Institution and Sara Russell, Natural History Museum

A bright fireball streaked across the sky above mountains, glaciers and spruce forest near the town of Revelstoke in British Columbia, Canada, on the evening of March 31, 1965. Fragments of this meteorite, discovered by beaver trappers, fell over a lake. A layer of ice saved them from the depths and allowed scientists a peek into the birth of the solar system.

Nearly 60 years later, NASA’s OSIRIS-REx mission returned from space with a sample of an asteroid named Bennu, similar to the one that rained rocks over Revelstoke. Our research team has published a chemical analysis of those samples, providing insight into how some of the ingredients for life may have first arrived on Earth.

Born in the years bracketing the Revelstoke meteorite’s fall, the two of us have spent our careers in the meteorite collections of the Smithsonian Institution in Washington, D.C., and the Natural History Museum in London. We’ve dreamed of studying samples from a Revelstoke-like asteroid collected by a spacecraft.

Then, nearly two decades ago, we began turning those dreams into reality. We joined NASA’s OSIRIS-REx mission team, which aimed to send a spacecraft to collect and return an asteroid sample to Earth. After those samples arrived on Sept. 24, 2023, we got to dive into a tale of rock, ice and water that hints at how life could have formed on Earth.

The CI chondrites and asteroid Bennu

To learn about an asteroid – a rocky or metallic object in orbit around the Sun – we started with a study of meteorites.

Asteroids like Bennu are rocky or metallic objects in orbit around the Sun. Meteorites are the pieces of asteroids and other natural extraterrestrial objects that survive the fiery plunge to the Earth’s surface.

We really wanted to study an asteroid similar to a set of meteorites called chondrites, whose components formed in a cloud of gas and dust at the dawn of the solar system billions of years ago.

The Revelstoke meteorite is in a group called CI chondrites. Laboratory-measured compositions of CI chondrites are essentially identical, minus hydrogen and helium, to the composition of elements carried by convection from the interior of the Sun and measured in the outermost layer of the Sun. Since their components formed billions of years ago, they’re like chemically unchanged time capsules for the early solar system.

Advertisement

So, geologists use the chemical compositions of CI chondrites as the ultimate reference standard for geochemistry. They can compare the compositions of everything from other chondrites to Earth rocks. Any differences from the CI chondrite composition would have happened through the same processes that formed asteroids and planets.

CI chondrites are rich in clay and formed when ice melted in an ancient asteroid, altering the rock. They are also rich in prebiotic organic molecules. Some of these types of molecules are the building blocks for life.

This combination of rock, water and organics is one reason OSIRIS-REx chose to sample the organic-rich asteroid Bennu, where water and organic compounds essential to the origin of life could be found.

Evaporites − the legacy of an ancient brine

Ever since the Bennu samples returned to Earth on Sept. 24, 2023, we and our colleagues on four continents have spent hundreds of hours studying them.

The instruments on the OSIRIS-REx spacecraft made observations of reflected light that revealed the most abundant minerals and organics when it was near asteroid Bennu. Our analyses in the laboratory found that the compositions of these samples lined up with those observations.

The samples are mostly water-rich clay, with sulfide, carbonate and iron oxide minerals. These are the same minerals found in CI chondrites like Revelstoke. The discovery of rare minerals within the Bennu samples, however, surprised both of us. Despite our decades of experience studying meteorites, we have never seen many of these minerals.

We found minerals dominated by sodium, including carbonates, sulfates, chlorides and fluorides, as well as potassium chloride and magnesium phosphate. These minerals don’t form just when water and rock react. They form when water evaporates.

Advertisement

We’ve never seen most of these sodium-rich minerals in meteorites, but they’re sometimes found in dried-up lake beds on Earth, like Searles Lake in California.

Bennu’s rocks formed 4.5 billion years ago on a larger parent asteroid. That asteroid was wet and muddy. Under the surface, pockets of water perhaps only a few feet across were evaporating, leaving the evaporite minerals we found in the sample. That same evaporation process also formed the ancient lake beds we’ve seen these minerals in on Earth.

Bennu’s parent asteroid likely broke apart 1 to 2 billion years ago, and some of the fragments came together to form the rubble pile we know as Bennu.

These minerals are also found on icy bodies in the outer solar system. Bright deposits on the dwarf planet Ceres, the largest body in the asteroid belt, contain sodium carbonate. The Cassini mission measured the same mineral in plumes on Saturn’s moon Enceladus.

We also learned that these minerals, formed when water evaporates, disappear when exposed to water once again – even with the tiny amount of water found in air. After studying some of the Bennu samples and their minerals, researchers stored the samples in air. That’s what we do with meteorites.

Unfortunately, we lost these minerals as moisture in the air on Earth caused them to dissolve. But that explains why we can’t find these minerals in meteorites that have been on Earth for decades to centuries.

Fortunately, most of the samples have been stored and transported in nitrogen, protected from traces of water in the air.

Advertisement

Until scientists were able to conduct a controlled sample return with a spacecraft and carefully curate and store the samples in nitrogen, we had never seen this set of minerals in a meteorite.

An unexpected discovery

Before returning the samples, the OSIRIS-REx spacecraft spent over two years making observations around Bennu. From that two years of work, researchers learned that the surface of the asteroid is covered in rocky boulders.

We could see that the asteroid is rich in carbon and water-bearing clays, and we saw veins of white carbonate a few feet long deposited by ancient liquid water. But what we couldn’t see from these observations were the rarer minerals.

We used an array of techniques to go through the returned sample one tiny grain at a time. These included CT scanning, electron microscopy and X-ray diffraction, each of which allowed us to look at the rock at a scale not possible on the asteroid.

Cooking up the ingredients for life

From the salts we identified, we could infer the composition of the briny water from which they formed and see how it changed over time, becoming more sodium-rich.

This briny water would have been an ideal place for new chemical reactions to take place and for organic molecules to form.

While our team characterized salts, our organic chemist colleagues were busy identifying the carbon-based molecules present in Bennu. They found unexpectedly high levels of ammonia, an essential building block of the amino acids that form proteins in living matter. They also found all five of the nucleobases that make up part of DNA and RNA.

Advertisement

Based on these results, we’d venture to guess that these briny pods of fluid would have been the perfect environments for increasingly complicated organic molecules to form, such as the kinds that make up life on Earth.

When asteroids like Bennu hit the young Earth, they could have provided a complete package of complex molecules and the ingredients essential to life, such as water, phosphate and ammonia. Together, these components could have seeded Earth’s initially barren landscape to produce a habitable world.

Without this early bombardment, perhaps when the pieces of the Revelstoke meteorite landed several billion years later, these fragments from outer space would not have arrived into a landscape punctuated with glaciers and trees.

Timothy J McCoy, Supervisory Research Geologist, Smithsonian Institution and Sara Russell, Professor of Planetary Sciences, Natural History Museum

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Please leave this field empty

Want more stories
“Your morning jolt of Inspiring & Interesting Stories!”

Sign up to receive awesome articles directly to your inbox.

We don’t spam! Read our privacy policy for more info.

Please check your inbox or spam folder to confirm your subscription.

Advertisement