First successful flight on December 17, 1903

On this date, 120 years ago, two Ohio brothers – Wilbur and Orville Wright – made the first bonafide, manned, controlled, heavier-than-air flight. It was the first airplane, and it took off at 10:35 a.m. with Orville Wright on board as pilot. He flew their vehicle, called the Flyer, for 12 seconds over 40 yards (about 37 meters) of sandy ground just outside Kitty Hawk, North Carolina. The Wright brothers succeeded where numerous other talented visionaries failed.

Two years later, the Wrights wrote in a patent application that their airplane design:

… provide[s] means for guiding the machine both vertically and horizontally … combining lightness, strength, convenience of construction, and certain other advantages.

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The story of the Wright brothers

Were the Wright brothers destined for the skies? It’s known that their father gave them a rubber-band-powered flying toy when they were still children. The toy was made of cork and bamboo with a paper body.

By 1899 – when Wilbur was 33 years old and Orville was 28 – the brothers were already learning everything they could about the science of aeronautics and the history of attempted human flight. Their first airplanes were gliders, which they tested on the long, isolated beaches of Kitty Hawk.

By 1902, they had built a glider that could be manned and controlled by a human pilot. It held a world record for gliding over 200 yards (about 183 meters).

Their first powered aircraft had a little over a 40-foot (12-meter) wingspan, weighed 750 lbs (340 kg), and had a 12-horsepower engine.

That first flight in December 1903 marked the beginning of a new era of global travel and interrelatedness.

By the time they received their patent for their airplane in 1906, several other aviators of the day claimed to have been the first to use the Wrights’ method of turning the airplane by warping or twisting the wings. But this part of the design, too, was included in the Wrights’ patent. In 2013, a story came to light about another would-be aviator, Gustave Whitehead, whose first flight supposedly beat the Wright brothers by two years. Thus far, that story has not been supported and is not accepted by aviation scholars.

Bottom line: The Wright brothers flew their first airplane for 12 seconds over 40 yards (about 37 meters) of sandy ground just outside Kitty Hawk, North Carolina, on December 17, 1903.

Read more: Bumpy flight? Here’s how clouds affect air travel

The post The Wright brothers succeeded 120 years ago first appeared on EarthSky.

Reprinted from a December 12, 2023, statement from the SETI Institute. Edits by EarthSky. Video by EarthSky.

SETI team ‘converses’ with a humpback whale

SETI stands for the Search for Extraterrestrial Intelligence. On December 12, 2023, a team of scientists from the SETI Institute, University of California Davis and the Alaska Whale Foundation, said they had a close encounter with a non-human (aquatic) intelligence. The Whale-SETI team has been studying humpback whale communication systems in an effort to develop what SETI researchers call “intelligence filters” in the search for extraterrestrial intelligence.

In response to a recorded humpback ‘contact’ call played into the sea via an underwater speaker, a humpback whale named Twain approached and circled the team’s boat, while responding in a conversational style to the whale ‘greeting signal.’

As a matter of fact, during the 20-minute exchange, Twain responded to each playback call and matched the interval variations between each signal.

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A description and analysis of the encounter appears in the November 29, 2023, issue of the journal Peer J, titled: “Interactive Bioacoustic Playback as a Tool for Detecting and Exploring Nonhuman Intelligence: Conversing with an Alaskan Humpback Whale.”

According to the lead author Brenda McCowan of U.C. Davis:

We believe this is the first such communicative exchange between humans and humpback whales in the humpback language.

Coauthor Fred Sharpe of the Alaska Whale Foundation said:

Humpback whales are extremely intelligent, have complex social systems, make tools – nets out of bubbles to catch fish – and communicate extensively with both songs and social calls.

Communicating with non-human intelligence

Similar to studying Antarctica as a proxy for Mars, the Whale-SETI team is studying intelligent, terrestrial, non-human communication systems to develop filters to apply to any extraterrestrial signals received. With this in mind, the mathematics of information theory to quantify communicative complexity – for example rule structure embedded in a received message – will be utilized.

According to Laurance Doyle, a coauthor on the paper, of the SETI Institute:

Because of current limitations on technology, an important assumption of the search for extraterrestrial intelligence is that extraterrestrials will be interested in making contact and so target human receivers. This important assumption is certainly supported by the behavior of humpback whales.

Bottom line: SETI researchers are studying how humpback whales communicate. This may eventually help us communicate with non-human intelligence of an alien civilization.

Source: Interactive Bioacoustic Playback as a Tool for Detecting and Exploring Nonhuman Intelligence: Conversing with an Alaskan Humpback Whale

Via SETI

Read more: SETI looks to Milky Way’s heart for alien signals

The post Will humpback whales train us to communicate with aliens? first appeared on EarthSky.

The University College London published this article on December 4, 2023. Reprinted here with permission. Edits by EarthSky.

Einstein’s gravity and quantum mechanics

Modern physics is founded upon two pillars. One is quantum theory, which governs the smallest particles in the universe. The other is Einstein’s theory of general relativity, which explains gravity through the bending of spacetime. But these two theories are in contradiction with each other, and a reconciliation has remained elusive for over a century.

The prevailing assumption has been to modify Einstein’s theory of gravity, or “quantized” to fit within quantum theory. This is the approach of two leading candidates for a quantum theory of gravity, string theory and loop quantum gravity.

But Jonathan Oppenheim at University College London Physics & Astronomy has developed a new theory. In a new paper in the peer-reviewed open-access journal Physical Review X (PRX), he challenges that consensus and takes an alternative approach by suggesting that spacetime may be classical. That is, not governed by quantum theory at all.

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Here’s how Einstein’s gravity and quantum mechanics works

Instead of modifying spacetime, the theory – dubbed a “postquantum theory of classical gravity” – modifies quantum theory. It predicts an intrinsic breakdown in predictability that is mediated by spacetime itself. This results in random and violent fluctuations in spacetime that are larger than envisaged under quantum theory, rendering the apparent weight of objects unpredictable if measured precisely enough.

A second paper, published simultaneously in the peer-reviewed, open-access journal Nature Communications and led by Oppenheim’s former Ph.D. students, looks at some of the consequences of the theory. It also proposes an experiment to test it: to measure a mass very precisely to see if its weight appears to fluctuate over time.

For example, the International Bureau of Weights and Measures in France routinely weighs a 1 kilogram mass, which used to be the 1kg standard. If the fluctuations in measurements of this 1kg mass are smaller than required for mathematical consistency, they can rule out that theory.

A 5,000:1 odds bet

The outcome of the experiment, or other evidence emerging that would confirm the quantum versus classical nature of spacetime, is the subject of a 5,000:1 odds bet between Professor Oppenheim and theoretical physicists Carlo Rovelli and Geoff Penington. Rovelli and Penington are leading proponents of quantum loop gravity and string theory, respectively.

For the past five years, the UCL research group has been stress-testing the theory and exploring its consequences.

Professor Oppenheim said:

Quantum theory and Einstein’s theory of general relativity are mathematically incompatible with each other. So it’s important to understand how this contradiction is resolved. Should spacetime be quantized, or should we modify quantum theory, or is it something else entirely? Now that we have a consistent fundamental theory in which spacetime does not get quantized, it’s anybody’s guess.

The experimental proposal

Co-author Zach Weller-Davies, who, as a Ph.D. student at UCL, helped develop the experimental proposal and made key contributions to the theory itself, said:

This discovery challenges our understanding of the fundamental nature of gravity but also offers avenues to probe its potential quantum nature.

We have shown that if spacetime doesn’t have a quantum nature, then there must be random fluctuations in the curvature of spacetime which have a particular signature that can be verified experimentally.

In both quantum gravity and classical gravity, spacetime must be undergoing violent and random fluctuations all around us, but on a scale which we haven’t yet been able to detect. But if spacetime is classical, the fluctuations have to be larger than a certain scale, and this scale can be determined by another experiment where we test how long we can put a heavy atom in superposition* of being in two different locations.

The analytical and numerical calculations of co-authors Carlo Sparaciari and Barbara Šoda helped guide the project. They expressed hope that these experiments could determine whether the pursuit of a quantum theory of gravity is the right approach.

More about the proposal

Šoda (formerly UCL Physics & Astronomy, now at the Perimeter Institute of Theoretical Physics, Canada) said:

Because gravity is made manifest through the bending of space and time, we can think of the question in terms of whether the rate at which time flows has a quantum nature, or classical nature.

And testing this is almost as simple as testing whether the weight of a mass is constant, or appears to fluctuate in a particular way.

Sparaciari (UCL Physics & Astronomy) said:

While the experimental concept is simple, the weighing of the object needs to be carried out with extreme precision.

But what I find exciting is that starting from very general assumptions, we can prove a clear relationship between two measurable quantities, the scale of the spacetime fluctuations, and how long objects like atoms or apples can be put in quantum superposition of two different locations. We can then determine these two quantities experimentally.

Weller-Davies added:

A delicate interplay must exist if quantum particles such as atoms are able to bend classical spacetime. There must be a fundamental trade-off between the wave nature of atoms, and how large the random fluctuations in spacetime need to be.

Einstein’s gravity and quantum mechanics background

Quantum mechanics. All the matter in the universe obeys the laws of quantum theory, but we only really observe quantum behavior at the scale of atoms and molecules. Quantum theory tells us that particles obey Heisenberg’s uncertainty principle, and we can never know their position or velocity at the same time. In fact, they don’t even have a definite position or velocity until we measure them. Particles like electrons can behave more like waves and act almost as if they can be in many places at once (more precisely, physicists describe particles as being in a “superposition” of different locations).

Quantum theory governs everything from the semiconductors that are ubiquitous in computer chips, to lasers, superconductivity and radioactive decay. In contrast, we say that a system behaves classically if it has definite underlying properties. A cat appears to behave classically: it is either dead or alive, not both, nor in a superposition of being dead and alive. Why do cats behave classically, and small particles quantumly? We don’t know, but the postquantum theory doesn’t require the measurement postulate, because the classicality of spacetime infects quantum systems and causes them to localize.

About gravity

Einstein’s gravity. Newton’s theory of gravity gave way to Einstein’s theory of general relativity (GR), which holds that gravity is not a force in the usual sense. Instead, heavy objects such as the sun bend the fabric of spacetime in such a way that causes Earth to revolve around it. Spacetime is just a mathematical object consisting of the three dimensions of space, and time considered as a fourth dimension. General relativity predicted the formation of black holes and the Big Bang. It holds that time flows at different rates at different points in space, and the GPS in your smartphone needs to account for this to properly determine your location.

Illustration at top

At the top of this article is an artistic version of Figure 1 in the PRX paper. It depicts an experiment in which heavy particles (illustrated as the moon) cause an interference pattern (a quantum effect), while also bending spacetime. The hanging pendulums depict the measurement of spacetime. The actual experiment typically uses Carbon-60, one of the largest known molecules. The UCL calculation indicates that the experiment should also use higher density atoms such as gold. Image via Isaac Young/ University College London. Used with permission.

Physical Review X paper
Nature Communications paper
Public lecture by Professor Jonathan Oppenheim in January 2024
Professor Oppenheim’s academic profile
UCL Physics & Astronomy
UCL Mathematical & Physical Sciences

Bottom line: Einstein’s gravity and quantum mechanics are the two bases for modern physics. But these two theories contradict each other. Have we reached a reconciliation?

Via UCL

The post Einstein’s gravity and quantum mechanics united at last? first appeared on EarthSky.

The Audubon Society’s Christmas Bird Count is one of the longest-running citizen science projects. It had a modest beginning on Christmas Day in 1900. And it’s since become a strong data-gathering project to study bird population trends. This year’s count – the 124th – runs from December 14, 2023, to January 5, 2024. You have to sign up in advance, and the signup has already begun. Go here to sign up for the Christmas Bird Count 2023.

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Audubon Christmas Bird Count – how it’s done

The Christmas Bird Count is a carefully run event. Each count site is a 15-mile (24-km) wide circle; you can see what it looks like by zooming in on this map to inspect a region near you. Counts for each circle are organized by a “circle compiler.” On the day of the count (set by the circle’s compiler), people head out to designated routes within a circle to count every species and number of birds that they see and hear during the day. And, if you live within the range of a count site, you can also tally the birds you see in your yard and at the feeder.

To participate in the count – it’s free – you need to sign up with a local circle compiler at the Audubon’s website. If you’re a beginning birder, you’ll be matched up with a more experienced birder. Make sure you register early, because the compiler will need time to organize the event.

In addition, you can share your bird count photographs and experiences on social media with the hashtag #ChristmasBirdCount. We here at EarthSky would love to have you send us your photographs, too!

Audubon Christmas Bird Count history

In some parts of the U.S., there used to be bird-hunting competitions on Christmas Day. However, Frank M. Chapman, an ornithologist at the American Museum of Natural History, came up with an alternative, an activity to count birds in a given area each Christmas to build up a record of their numbers.

That first count was in 1900. Overall, 27 birders conducted counts at 25 sites, tallying about 89 bird species.

Since then, the Christmas Bird Count has come a long way. It’s continued annually since the inaugural event, growing in volunteers and census sites. For instance, the 121st Christmas Bird Count took place from December 14, 2020, to January 5, 2021. That count occurred at 2,459 locations, with 72,815 volunteers in the U.S., Canada, Latin America, the Caribbean and Pacific Islands. Altogether, volunteers observed a total of 2,355 bird species.

What have we learned from these counts?

Additionally, Audubon and other research groups use Christmas Bird Count data to monitor population trends that will help guide conservation efforts. To date, scientists have published more than 300 peer-reviewed studies based on this data. The data is also used by federal agencies to craft policy on bird conservation.

Each annual count provides a snapshot of the birds at a given time and place. It’s hard to draw conclusions from one year to the next, because changes happen gradually. To understand trends, scientists do a statistical analysis of data taken over several years.

Warning signs of environmental degradation show up in declines of bird populations in some types of habitats. For instance, the sharpest declines in bird populations have been in grassland habitats, followed by coastal habitats.

Bird census data also informs scientists about the effects of climate change on wildlife. In a 2014 report, National Audubon predicted how the ranges of 588 species of birds in North America could be affected by climate change. They concluded that more than 314 species could lose over 50% of their current climatic range by 2080.

Bottom line: Audubon’s 124th Christmas Bird Count will take place from December 14, 2023, to January 5, 2024. You can join in to help collect important data about birds. Find out how to join in the Audubon Christmas Bird Count.

The post Audubon Christmas Bird Count signup has begun first appeared on EarthSky.

If you’re born in December, you have a choice of three birthstones: turquoise, zircon and tanzanite. Turquoise, a soft gemstone used in jewelry and ornaments, has a rich history dating to antiquity. Zircons are not well-known gemstones, but they make absolutely stunning jewelry. Tanzanite is an exquisite clear blue-violet crystal found only in Tanzania.

Why do some months have one birthstone but others have two or three? According to the website onecklace.com, multiple stones for some months allow more affordable options in addition to the traditional and more expensive stones.

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December birthstone: turquoise

To chemists and geologists, turquoise is copper aluminum phosphate. It forms when rainwater or melted snow percolates through copper ore deposits called copper porphyry. Water interacts with copper sulfides in the ore to form an acidic solution. This copper-carrying acidic water, when it reacts with aluminum and potassium in the rocks, precipitates turquoise into cavities. You can find turquoise in weathered volcanic rock and sedimentary rock in arid locations.

Turquoise is a relatively soft gemstone, with a Mohs scale hardness of five to six. You can scratch or break turquoise with moderate force. Oil and pigments easily discolor this porous opaque stone. It also changes color when it loses some of its water content.

Hard, relatively non-porous, compact stones have the best appearance because the stone can be finely polished. “Softer” varieties that are more porous are treated with oil, paraffin, liquid plastic or water glass to enhance its durability and color.

Copper gives a sky-blue shade to turquoise, while iron gives it a greener tone. The most valued variety of turquoise is an intense sky-blue color, like the color of a robin’s egg. Ochre and brown-black veins, often found in the gemstones, are inclusions from the surrounding rock matrix.

Turquoise facts

Some of the best turquoise in the world comes from Iran, famous for its sky-blue stones from Neyshabur. In Egypt, people have mined turquoise in the Sinai Peninsula for over 5,000 years. Turquoise is found in many U.S. southwestern states: Arizona, California, Colorado, New Mexico and Nevada. This stone also occurs in Afghanistan, Australia, China, India, Tibet, Mexico and Brazil.

The word turquoise originated from the French phrase pierre turquoise, meaning Turkish stone. That’s because Venetian traders brought the gemstone to Europe after acquiring it from traders in Turkey.

In antiquity, turquoise was used as jewelry by the ruling classes of civilizations in Africa, Asia and the Americas. People have found beads dating to the late 6th millennium BCE in ancient Iraq. Turquoise bracelets were on the arm of a woman in the tomb of Zer, a pharaoh that ruled Egypt around 3000 BCE. A 3,700-year-old dragon relic from the Xia Dynasty, made from over 2,000 pieces of turquoise, was in the tomb of a nobleman in central China.

Turquoise in the Americas

Turquoise has a rich history in the American Southwest. Native Americans have been using this gemstone to create jewelry and ornamental pieces for several thousand years. The Apache, Navajo, Pueblo, and Zuni are known for their turquoise jewelry.

In the Zuni language, the word for turquoise is sky stone. During the growing season in summer, Pueblo dancers wear turquoise to encourage rainfall. The Navajo associate turquoise with health and protection, using the stone in important rites of passage. While the Apache believed that turquoise lay at the end of a rainbow, and that turquoise attached to a bow or gun ensured an accurate aim.

Turquoise was a part of pre-Columbian cultures in Mexico, Central America, and South America. In Peru, prehistoric tribes made small objects such as beads, figurines and artifacts with turquoise inlays. For the Aztecs, turquoise was popular in ornaments. It also had important religious and ceremonial uses. For example, a high priest involved in human sacrifice wore a turquoise pendant hung from his underlip. A notable Aztec art form was intricate turquoise mosaics, like that of a turquoise mosaic mask used in the interment of a king.

Turquoise lore

Some people consider turquoise a love charm. When received as a gift, it is supposed to symbolize a pledge of affection. Shakespeare used this lore in “The Merchant of Venice.” In it, Leah gave a turquoise ring to Shylock when he was a bachelor, hoping it would win his affections so he would ask her to marry him.

There are many other superstitions associated with turquoise. In the twelfth century, an Arabian writing declared: “the turquoise shines when the air is pure and becomes pale when it is dim.” They also believed that its color changed with the weather. In the 13th century, people believed it would protect its owner from injury if he fell off a horse.

George Frederick Kunz’s book, The Curious Lore of Precious Stones, stated that diamonds and turquoises supposedly lost their powers if sold:

The spirit dwelling in the stone was thought to take offence at the idea of being bought and sold, and was supposed to depart from the stone, leaving it nothing more than a bit of senseless matter. If, however, the diamond (or turquoise) were offered as a pledge of love or friendship, the spirit was quite willing to transfer its good offices from one owner to another.

There were also health myths associated with turquoise. People believed the stone changed color when its wearer became ill. Some said it was an effective treatment for scorpion stings and pain from evil influences. Just looking at turquoise supposedly strengthen the eyes.

December birthstone: zircon

Zircon is a mineral formed of the elements zirconium and silicon (zirconium silicate). Small crystals, just a few millimeters in size, are commonly found in most igneous rock. With a Mohs scale hardness of 7.5, zircon is hard enough to survive the geologic forces that create metamorphic and sedimentary rock. But large zircon crystals are rare. They’re formed mainly in pegmatites (coarse-grained igneous rock) and carbonatites. But due to weathering of gem-bearing rocks, most zircons are in alluvial and beach deposits.

The name zircon may have come from the Arabic words zarquin, meaning red. Or perhaps from the Persian word zargus, meaning gold-colored.

Major sources of gemstone-quality zircon are Thailand, Cambodia, Vietnam and Sri Lanka. The gemstones also occur in Myanmar, France, Norway, Australia and Canada.

Colors of zircon

Over vast spans of geologic time, forces have worked within zirconium silicate crystals to change their molecular structure and color. Uranium and thorium inclusions emit radiation that alters the original crystal structure. A glass-like material forms, with colors of red to brown, orange and yellow. Green is the rarest of the natural colors. Since the 1920s, most gemstones have undergone heat treatment to bring out their colors. This produces colorless zircons, as well as blue and golden stones.

The creation of blue stones is in an interesting story relayed in “Gems and Crystals” by Anna S. Sofianides and George E. Harlow:

In the 1920s, a new blue gemstone suddenly appeared in the market. Endowed with spectacular brilliance, it was an immediate hit.

The creation of the blue zircon

The gems, it turned out, were zircons, normally brown to green, but never before blue. George F. Kunz, the legendary Tiffany gemologist, immediately suspected trickery; not only were there extraordinary stones available in abundance, but they were available all over the world! Upon Kunz’s behest, a colleague made inquiries during a trip to Siam (Thailand) and learned that a large deposit of unattractive brown zircon had stimulated color-improvement experimentation by local entrepreneurs. Heating in an oxygen-free environment made the drab material into “new” blue stones, which vendors sent to outlets worldwide. Even after finding out about the deception, the market simply accepted the information and the demand for the new gems continued unabated.

Among zircon customers, blue stones are a clear favorite. Red and green colors are also valuable. Colorless zircons are excellent imitators of diamonds, in appearance only, with a brilliant fire almost as dazzling as the real thing. However, zircon can be brittle and cutting takes great care. It breaks with a well-placed knock, due to internal stresses in the crystal caused by radiation damage and heat treatment. But it remains in demand for its stunning beauty. In addition, other factors that affect pricing of the gemstones are clarity and an absence of visible inclusions.

Zircon lore

Green zircon was among the stones of the Kalpa Tree of the Hindu religion, where it represented the tree’s foliage. This tree was a symbolic offering to the gods. Hindu poets of the 19th century described it as part of a glowing ensemble of precious stones that also included sapphires, diamonds and topaz.

The hyacinth and jacinth, reddish-brown and orange-red varieties of zircon, were a favorite stone of ancient Arabs, even mentioned in the famed “Arabian Nights.”

During the 14th century, zircon was popular as a safeguard against the Black Death, the great plague that wiped out a quarter of the population of Europe. People believed the stone possessed healing powers: to induce sleep, as an antidote against poison, and as an aid to digestion.

December birthstone: tanzanite

Tanzanite is an unusual form of the mineral zoisite (calcium aluminium hydroxyl sorosilicate). Its colors, blue and violet, are due to the presence of vanadium in the zoisite crystals. This gemstone formed 585 million years ago under extreme heat during intense plate tectonic activity, in a place that would someday become Mount Kilimanjaro in northern Tanzania.

Today, you can only find tanzanite in the Merelani Hills near the foot of Mount Kilimanjaro.

Colors from different angles

In its natural form, tanzanite appears brown, yellowish green, blue and violet, flashing these colors when viewed from different angles. This phenomenon is pleochroism, where you can see different colors depending on how light hits the gemstone.

The type of lighting can also make a difference. Under fluorescent lights, tanzanite appears bluer, while under incandescent light, more violet hues emerge.

However, most crystals used in jewelry received doses of heat to remove the brownish color found in the natural tanzanite. The results are more intensely blue and violet gems. On rare occasions, heated stones can produce a green gem with secondary blue and violet colors. For cut gems, cutters can influence their overall color by how they craft the gem.

Tanzanite’s recent history

While most birthstones have histories spanning hundreds and even thousands of years, tanzanite’s story began in 1967. A Masai tribesman found unusual clear violet-blue crystals in the Merelani Hills in northern Tanzania. He notified a local tailor and prospector, Manuel d’Souza, who, upon finding the gemstones, filed the first of many mining claims.

Initially, d’Souza thought they were sapphires. But no one knew for sure. The stones made their way to geologists at the Gemological Institute of America where they identified them as an unusual form of zoisite.

And then, the famed jewelry purveyors, Tiffany & Company, took an interest in the gem. In 1968, they began a marketing campaign. To make the gems more appealing to buyers, they renamed blue zoisite to tanzanite, in honor of its country of origin. Finally, in 2002, the American Gem Trade Association selected tanzanite to join turquoise and zircon as December birthstones.

Beyond the December birthstone: birthstones for all months

January birthstone
February birthstone
March birthstone
April birthstone
May birthstone
June birthstone
July birthstone
August birthstone
September birthstone
October birthstone
November birthstone
December birthstone

Bottom line: As a matter of fact, December babies have three choices for their birthstone. Turquoise, zircon and tanzanite are the birthstones for December.

The post December birthstone: turquoise, zircon or tanzanite first appeared on EarthSky.

Many saw this rare waterspout over Sun Moon Lake in Nantou, Taiwan, yesterday (November 16, 2023). Bob Kuo – a longtime contributor of interesting photos to EarthSky’s community page – wrote:

A rare treat for tourists! We were wrapping up our first day of activities at the famous landmark in Taiwan, the beautiful Sun Moon Lake. As we lounged over the balcony overlooking the ferry pier, it began to rain and there was a strong gust of wind. I noticed a faint funnel column began to appear and realized it was a waterspout forming right in front of me! I didn’t waste time looking for my camera and just fired away with my phone to take photos and a short video. This rare sight lasted only for about 2 minutes.

What a beautiful sight, Bob! Thank you for sharing.

Radio Taiwan International (RTI) posted a video of the event, which you can see below. In an article at RTI, Filip Leskovsky wrote:

Waterspouts are common in tropical and subtropical waters; however, this is the first time spectators at Sun Moon Lake have witnessed this phenomenon …

Meteorologists believe that the waterspout was caused by a cold front that passed through the area. The cold air from the front interacted with the warm air over the lake, creating a strong upward motion that caused the waterspout to form.

A witness described the waterspout as looking like a waterfall coming down from the clouds. Another witness who also saw the waterspout said that she thought it was just a black cloud raining, but soon realized that it was a waterspout. She said she was very lucky to witness this …

A waterspout like this is a rare sight and can be a reminder of the power of nature.

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Video from people who saw it

Bottom line: An EarthSky community member caught this rare waterspout over Sun Moon Lake on November 16, 2023. What a catch! Thank you, Bob!

The post Wow! A rare waterspout over Sun Moon Lake, Taiwan first appeared on EarthSky.

Lost tool bag captured on video

The tool bag recently lost by NASA astronauts during a spacewalk is now orbiting Earth and is surprisingly visible to stargazers. The object can appear as bright as a 6th-magnitude star. You can see it in the video above by Eddie Irizzary and Nelson Ortega taken from Añasco, Puerto Rico, on November 11, 2023, around 7:15 pm AST (23:15 UTC). At the time, the tool bag was passing close to where we see Delta Aquilae and Altair, the brightest star in the constellation Aquila the Eagle. Orbital tracking and predictions confirm the object in this video is, in fact, the tool bag that astronauts Jasmin Moghbeli and Loral O’Hara accidentally lost on November 2, 2023.

The tool bag changes slightly in brightness, suggesting the object is tumbling as it orbits our planet. Although the tool bag was ahead of the International Space Station (ISS) by about a minute or two shortly after the incident, it is gradually appearing farther ahead of the ISS as it loses altitude.

In fact, it was already about five minutes ahead of the ISS on November 11 (the date the video was taken). By mid-November, the tool bag should be ahead by about ten minutes.

Observations also indicate that as the tool bag loses altitude, it has drifted slightly to the east, or left, of the ISS’s trajectory.

In the last segment of the video above, the ISS appears. It was passing close to where we see the bright star Altair.

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How long will it be up there?

The tool bag should remain in orbit around Earth for a few months yet. Unlike the ISS, the tool bag will rapidly descend in orbit until it reaches about 70 miles (113 km). At that point it will disintegrate. New estimates indicate the tool bag should reenter the atmosphere between March and July of 2024.

How to see the tool bag with binoculars

It’s surprisingly bright (for a tool bag), shining just below the limit of visibility to the unaided eye at around magnitude +6. That means some sky observers should be able to pick it up with binoculars.

The first step to seeing it is checking if you have a visible pass of the ISS. Check here for how to see ISS in your sky. Your strategy will be to figure out the trajectory of the ISS and look for it before the space station crosses the sky. It’s already five minutes ahead of the ISS and will soon be nearly 10 minutes ahead.

If you get an image, please submit it to EarthSky Community Photos!

How did it get lost?

The spacewalkers were conducting repairs on assemblies that allow the ISS solar arrays to track the sun continuously. A blog post at SciTechDaily, which was describing the spacewalk, explained:

During the activity, one tool bag was inadvertently lost. Flight controllers spotted the tool bag using external station cameras. The tools were not needed for the remainder of the spacewalk. Mission Control analyzed the bag’s trajectory and determined that risk of recontacting the station is low and that the onboard crew and space station are safe with no action required.

The lost tool bag on social media

Last seen by @Astro_Satoshi while floating over Mount Fuji ? the 'Orbital Police' can confirm that the lost EVA gear is being tracked ? https://t.co/wz4MITmAfM pic.twitter.com/eksfu9fPFw

— Dr Meganne Christian (@astro_meganne) November 5, 2023

A tool bag was lost during last week’s EVA to replace a trundle bearing on the port solar alpha array. The object is now listed in the catalog as ID 1998-067WC/58229. The tool bag as a +6th magnitude ‘star’ currently about a minute ahead of the ISS.https://t.co/2YZf3PnjzV

— Dave Dickinson (@Astroguyz) November 6, 2023

The crew lock bag that floated free during the Nov 1 EVA-89 spacewalk has been cataloged as 58229 / 1998-067WC in a 415 x 416 km orbit

— Jonathan McDowell (@planet4589) November 5, 2023

Not the first time

And this isn’t the first time a NASA astronaut has lost a tool bag. On November 18, 2008, astronaut Heide Stefanyshyn-Piper was performing a similar repair at the ISS when she inadvertently lost a tool bag.

Some two months later, on January 12, 2009, the object was still visible ahead of ISS and was seen with binoculars by Joxelle Velazquez among others during a star party at Cabo Rojo, Puerto Rico. See the image below.

There’ve been earlier losses of astronauts’ items, too, to the junkyard of near-Earth orbit. Victor Tangermann at Futurism reported on November 3:

It’s far from the first time astronauts have lost track of tools in space. Back in 1965, NASA astronaut Ed White infamously lost a spare glove during a spacewalk outside of his Gemini 4 spacecraft. Over the decades, several other astronauts have lost other objects, from spare bolts in 2006 to an entire bag ironically containing a debris shield in 2017.

And, although NASA has determined that the 2023 tool bag isn’t on a trajectory that’s dangerous to the astronauts aboard the ISS at this time, the problem of litter in near-Earth orbit remains and is serious. As Tangermann wrote at Futurism:

The problem, of course, is that not every piece of space debris will stay out of the way of future space travelers.

And that is a sad truth.

Bottom line: NASA astronauts accidentally lost a tool bag during a spacewalk on November 2. Now, observers on the ground have caught the tool bag on video. See it here.

Via SciTechDaily

The post Lost tool bag from spacewalk caught on video first appeared on EarthSky.

State of Emergency: The Department of Civil Protection in Iceland has just ordered a mandatory evacuation of the city of Grindavík and the Svartsengi Power Station as a volcanic eruption appears imminent. Over 1,000 earthquakes reported over the past 24 hours. pic.twitter.com/VkPgBz61VR

— Nahel Belgherze (@WxNB_) November 11, 2023

Fagradalsfjall volcano appears poised to erupt again

The BBC and other media are reporting today (November 11, 2023) that Iceland has declared a state of emergency after a series of earthquakes raised fears of a volcanic eruption at Fagradalsfjall volcano. The BBC said that authorities have ordered the evacuation of thousands living in the town of Grindavík, a fishing town on the Southern Peninsula of Iceland. And BBC said:

The Icelandic Met Office says it is concerned large amounts of magma – molten rock- is spreading underground and could surface there.

Thousands of tremors have been recorded around the nearby Fagradalsfjall volcano in recent weeks.

And the Icelandic Met Office reported near midnight local time last night that:

The seismic activity has moved south towards Grindavík.

The tremors have been concentrated in Iceland’s Reykjanes Peninsula. This area had remained dormant to volcanic activity for 800 years before a 2021 eruption of Fagradalsfjall.

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Report from the Met Office in Iceland

The Icelandic Met Office had reported earlier on November 10:

Significant changes have occurred in the seismic activity measured near Sundhnjúkagígar north of Grindavík and deformation observed in the Reykjanes Peninsula this afternoon … In light of this outcome, the police chief in Suðurnes, in cooperation with the Civil Protection Authorities, has decided to evacuate Grindavík.

An emergency level of civil protection is now in effect. This is not an emergency evacuation. Residents of Grindavík are advised to proceed with caution.

At this stage, it is not possible to determine exactly whether and where magma might reach the surface. There are indications that a considerable amount of magma is moving in an area extending from Sundhnjúkagígum in the north towards Grindavík. The amount of magma involved is significantly more than what was observed in the largest magma intrusions associated with the eruptions at Fagradalsfjall.

Further data is being collected to calculate models that provide a more accurate picture of the magma intrusion. It is currently not possible to say when this work will be completed.

‘Panic’ at a popular tourist area in Iceland

Authorities called for calm, but the evacuations haven’t gone entirely smoothly. Associated Press (AP) reported on November 10 that there was “panic” at the Blue Lagoon geothermal spa – one of Iceland’s biggest tourist attractions. AP said the spa:

… closed temporarily as a swarm of earthquakes put the island nation’s most populated region on alert for a possible volcanic eruption.

Guests rushed to leave the spa’s hotels in the early hours of Thursday, after they were rattled awake shortly before 1 a.m. by a magnitude 4.8 quake, the strongest to hit the region since the recent wave of seismic activity began on October 25.

Bjarni Stefansson, a local taxi driver, described a scene of confusion when he arrived at the Retreat Hotel. Lava rocks had fallen on the roadway and the parking lot was jammed with 20 to 30 cabs.

‘There was a panic situation,’ Stefansson told The Associated Press. ‘People thought a volcanic eruption was about to happen.’

Watch the livestream

At this YouTube link, you can keep an eye on different views of the part of Iceland where the earthquakes have been happening. And – in the photos and video below – you can see some of the effects of the recent earthquakes.

Huge cracks have opened up on the Grindavík golf course in #Iceland due to the many earthquakes they have had….?

? Ragnar Visage pic.twitter.com/2RUK8mwpZH

— Volcaholic ? (@volcaholic1) November 11, 2023

Good morning all,

?Iceland declares state of emergency, evacuates residents over threat of volcanic eruption ?

Emergency in the city of Grindavik inIceland, is currently under mandatory evacuation, an earthquake every 5 second, Over 1,400 small earthquakes have been recorded… pic.twitter.com/QmuRYBzkhl

— Kernow Weather Team (@KWTWeather) November 11, 2023

When Fagradalsfjall volcano woke up

The Fagradalsfjall eruption of 2021 was unexpected. Since then, the volcano has become an attraction for local people and foreign tourists.

Another eruption, very similar to the 2021 eruption, began on August 3, 2022, and ceased on August 21, 2022. A third eruption appeared to the north of Fagradalsfjall on July 10, 2023, and ended on August 5, 2023.

Bottom line: Iceland declared a state of emergency on November 10, 2023, for the area around Fagradalsfjall volcano. It was dormant for 800 years until a 2021 eruption. Now it looks poised to erupt again.

Via BBC

Via Icelandic Met Office

Via AP

The post Iceland braces for eruption of Fagradalsfjall volcano first appeared on EarthSky.

The scientist behind Halley’s Comet

November 8, 1656, is the birthdate of English astronomer and mathematician Edmond Halley. Born near London, he grew to become the first to make the leap of the imagination required to understand that comets orbit our sun. And he was the first to calculate the orbit of a comet, now one of the most famous of all comets, named Comet Halley in his honor.

Halley was also friends with Isaac Newton and contributed to Newton’s development of the theory of gravity, which helped establish our modern era of science, in part by removing all doubt that we live on a planet orbiting around the sun.

When Halley’s Comet last appeared in Earth’s skies in 1986, an international fleet of spacecraft were there to meet it. This famous comet will return again in 2061 on its 76-year journey around the sun. It’s famous partly because it tends to be a bright comet in Earth’s skies. And the length of its orbit – approximately 76 years – isn’t so different from that of a human lifespan. So, most people can see Comet Halley once in a lifetime, while some lucky people might be able to see it twice.

But it’s also famous for another reason. In Edmond Halley’s time, people didn’t know that comets were like planets, bound in orbit by the sun. They didn’t know that some comets, like Halley’s Comet, return over and over.

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Halley’s prediction

In 1704, Halley became a professor of geometry at Oxford University. The following year, he published A Synopsis of the Astronomy of Comets. The book contains the parabolic orbits of 24 comets that graced Earth’s skies from 1337 to 1698.

It was in this book that Halley made his magnificent prediction.

The return of Halley’s Comet

In his book, Halley remarked on three comets that appeared in 1531, 1607 and 1682. He used Isaac Newton’s theories of gravitation and planetary motions to compute the orbits of these comets. He found remarkable similarities in their orbits. Then Halley made what was, at that time, a stunning prediction. He said these three comets must in fact be a single comet, which returns periodically every 76 years.

He then predicted the comet would return, saying:

Hence I dare venture to foretell, that it will return again in the year 1758.

Halley didn’t live to see his prediction verified. It was 16 years after his death that – right on schedule, in 1758 – the comet did return, amazing the scientific world and the public.

It was the first comet ever predicted to return. Thus, we now call it Halley’s Comet, in honor of Edmond Halley.

Halley, Flamsteed and a Mercury transit

The 17th century was an exciting time to be a scientist in England. The scientific revolution gave birth to the Royal Society of London when Halley was only a child. Members of the Royal Society – physicians and natural philosophers who were some of the earliest adopters of the scientific method – met weekly. The first Astronomer Royal was John Flamsteed, remembered in part for the creation of the Royal Observatory at Greenwich, which still exists today.

After entering Queen’s College in Oxford as a student in 1673, Halley met Flamsteed. Halley had the chance to visit him in his observatory on a few occasions, during which Flamsteed encouraged him to pursue astronomy.

At that time, Flamsteed’s project was to assemble an accurate catalog of the northern stars with his telescope. Halley thought he would do the same, but with stars of the Southern Hemisphere.

Halley’s Southern Hemisphere expedition

His journey southward began in November 1676, even before he obtained his university degree. He sailed aboard a ship from the East India Company to the island of St. Helena, still one of the most remote islands in the world and the southernmost territory occupied by the British. His father and King Charles II financed the trip.

Bad weather made Halley’s work difficult. But, despite this, when he turned to sail back home in January 1678, he brought records of the longitude and latitude of 341 stars and many other observations. One of these observations was a transit of Mercury, about which he wrote:

This sight … is by far the noblest astronomy affords.

Cracking the code of planetary motion

Halley published his catalog of southern stars by the end of 1678. And – as the first work of its genre – it was a huge success. No one had ever attempted to determine the locations of southern stars with a telescope before. The catalog was Halley’s glorious debut as an astronomer. In the same year, he received his M.A. from the University of Oxford and was elected a fellow of the Royal Society.

Halley visited Isaac Newton in Cambridge for the first time in 1684. A group of Royal Society members, including physicist and biologist Robert Hooke, architect Christopher Wren and Isaac Newton, were trying to crack the code of planetary motion. Halley was the youngest to join the trio in their mission to use mathematics to describe how – and why – the planets move around the sun. They were all competing against one another to find the solution first, which was very motivating. Their problem was to find a mechanical model that would keep the planet orbiting around the sun without it escaping the orbit or falling into the star.

Hooke and Halley determined that the solution to this problem would be a force that keeps a planet in orbit around a star and must decrease as the inverse square of its distance from the star. Today we know this as the inverse-square law.

Hooke and Halley were on the right track, but they were not able to create a theoretical orbit that would match observations, despite Wren donating a monetary prize.

Newton solves it

Halley explained the concept to Newton, also explaining that he couldn’t prove it. Newton, encouraged by Halley, developed Halley’s work into one of the most famous scientific works to this day, Mathematical Principles of Natural Philosophy, often referred to simply as Newton’s Principia.

Halley became Astronomer Royal

Halley is also known for his work in meteorology. He put his talent of giving meaning to great amounts of data to use by creating a map of the world in 1686.

The map showed the most important winds above the oceans and is the first meteorological chart ever published.

Halley kept traveling and working on many other projects, such as attempting to link mortality and age in a population. This data became important for actuaries calculating life insurance.

In 1720, Halley succeeded Flamsteed and became the second Astronomer Royal at Greenwich.

Bottom line: Astronomer Edmond Halley is famous for predicting the return of the comet that we now know as Halley’s Comet. Edmond was born on November 8, 1656.

The post Halley’s Comet is Edmond Halley’s namesake. Happy birthday, Edmond! first appeared on EarthSky.

Book review for “Totality”

Oscar Wilde once quipped that a book exhausting its subject only succeeds in exhausting its readers. I’m proud to present a book that stands as a notable exception to this rule: Totality: The Great North American Eclipse of 2024 by Mark Littmann and Fred Espenak. It’s one of the most enjoyable reads that I’ve had in a long time.

Edifying as well as entertaining, Littmann and Espenak masterfully interweave eclipse history, folklore, superstition, geography, science and technology. “Totality” is sure to charm people across the board, from novice to maven. The friendly and conversational style almost makes one forget to be intimidated by technicalities.

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Totality is nature’s grandest visual spectacle

Yes, a whole cavalcade of geeks contributed to the production of this great opus. Even so, these eclipse aficionados are more interested in sharing their joyous passion than in imposing a dissertation upon you. They – as much as anyone – can sympathize with the exasperating words of Alfonso X, King of Castile (1252), who complained:

If God had consulted with me before embarking upon creation, I would have recommended something simpler.

The theme of the book is simple and can’t be repeated often enough: A total eclipse of the sun counts as nature’s grandest visual spectacle. In fact, an eclipse chaser who witnessed 30 total solar eclipses hardly exaggerates in proclaiming:

In rating natural wonders, on a scale of 1 to 10, a total eclipse of the sun is a million.

Total solar eclipse once in 375 years

A total solar eclipse only comes once to your part of the world in an average of 375 years. If you live in North America, and the path of this upcoming total solar eclipse passes through your neighborhood, take full advantage. That’ll probably be your once-in-lifetime opportunity to witness a total eclipse of the sun in your own backyard. Absolutely nothing compares to the ultimate experience of standing inside a moon shadow.

Alas, the average figure of 375 years stated above proves to be quite misleading overall. For instance, people in Carbondale, Illinois, get to see two total solar eclipses in the span of seven years (2017 and 2024). Yet, the next total solar eclipse in Antwerp, Belgium, (on May 25, 2142) will be the first to occur there in at least seven centuries. (According to Jean Meeus in Mathematical Astronomy Morsels I, page 92.) No wonder King Alfonso X admonished the creator for the hard-to-fathom cosmos.

Treasure trove of information

The authors are begging and pleading with all those living on or near the path of the total solar eclipse (and those willing to travel) to enjoy nature’s greatest visible spectacle. Most likely, another total eclipse of the sun won’t happen in your neck of the woods for hundreds of years. So let this treasure trove of information ready you for the thrill of a lifetime.

Our tour guides – Mark Littmann and Fred Espenak – say in way of conclusion:

If the weather cooperates, the total eclipse of the sun on April 8, 2024, could mark the biggest outdoor spectator event in American history – a 2,140-mile-long (3,444-km-long) tailgate party to watch the heavenly performance of the moon and sun.

Bottom line: Read a book review of “Totality: The Great North American Eclipse of 2024” by Mark Littmann and Fred Espenak. Reviewed by Bruce McClure.

The post Media we love: Totality, The Great North American Eclipse of 2024 first appeared on EarthSky.