Astronomer reveals the exact minute of this year's summer solstice
The summer solstice marks the official start of summer. It brings the longest day and shortest night of the year for the 88 per cent of Earth 's people who live in the Northern Hemisphere.
People around the world traditionally observe the change of seasons with bonfires and festivals, and Fête de la Musique celebrations.
Astronomers can calculate an exact moment for the solstice, when Earth reaches the point in its orbit where the North Pole is angled closest to the Sun.
That moment will be at 10.42pm Eastern Time on June 20 this year - or 3.42am on June 21 in the United Kingdom.
In Europe, Africa and points eastward, the moment of the equinox falls on June 21 locally, making that the day of the solstice. From Earth, the Sun will appear farthest north relative to the stars. People living on the Tropic of Cancer, 23.5 degrees north of the Equator, will see the Sun pass straight overhead at noon.
Six months from now, the Sun will reach its southern extreme and pass overhead for people on the Tropic of Capricorn, and northerners will experience their shortest days of the year at the winter solstice.
The Sun's angle relative to Earth's equator changes so gradually close to the solstices that, without instruments, the shift is difficult to perceive for about 10 days. This is the origin of the word solstice, which means 'solar standstill.'
This slow shift means that daylight on June 20 is only about 2 seconds longer than on June 21, at mid-northern latitudes in the United States. It will be about a week before there's more than a minute change to the calculated amount of daylight. Even that's an approximation — Earth's atmosphere bends light over the horizon by different amounts depending on weather, which can introduce changes of more than a minute to sunrise and sunset times.
Monuments at Stonehenge in England, Karnak in Egypt, and Chankillo in Peru reveal that people around the world have taken note of the Sun's northern and southern travels for more than 5,000 years. From Stonehenge's circle of standing stones, the Sun will rise directly over an ancient avenue leading away to the northeast on the solstice.
We know little about the people who built Stonehenge, or why they went to such great effort to construct it, moving multi-ton stones from rock outcrops as far as 140 miles away.
All this to mark the spot on the horizon where the Sun returns each year to rest for a while before moving south again.
Perhaps they, like us, celebrated this signal of the coming change of seasons.
Stephen Schneider is a Professor of Astronomy at UMass Amherst.
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The Independent
32 minutes ago
- The Independent
What to know about the summer solstice in the UK
The summer solstice marks the official start of summer, occurring when Earth's North Pole is angled closest to the Sun, bringing the longest day and shortest night to the Northern Hemisphere. This year, the exact moment of the solstice will be at 10:42 PM Eastern Time on June 20, which translates to 3:42 AM on June 21 in the United Kingdom. People worldwide traditionally observe the change of seasons around the solstice with various celebrations, including bonfires, festivals, and Fête de la Musique. The word "solstice" means "solar standstill," reflecting how the Sun's angle appears to shift very gradually for about 10 days around this time. Ancient monuments like Stonehenge, Karnak, and Chankillo reveal that civilizations have tracked the Sun's northern and southern travels for over 5,000 years.
The Independent
an hour ago
- The Independent
Astronomer reveals the exact time of this year's summer solstice
The summer solstice marks the official start of summer. It brings the longest day and shortest night of the year for the 88 per cent of Earth 's people who live in the Northern Hemisphere. People around the world traditionally observe the change of seasons with bonfires and festivals, and Fête de la Musique celebrations. Astronomers can calculate an exact moment for the solstice, when Earth reaches the point in its orbit where the North Pole is angled closest to the Sun. That moment will be at 10.42pm Eastern Time on June 20 this year - or 3.42am on June 21 in the United Kingdom. In Europe, Africa and points eastward, the moment of the equinox falls on June 21 locally, making that the day of the solstice. From Earth, the Sun will appear farthest north relative to the stars. People living on the Tropic of Cancer, 23.5 degrees north of the Equator, will see the Sun pass straight overhead at noon. Six months from now, the Sun will reach its southern extreme and pass overhead for people on the Tropic of Capricorn, and northerners will experience their shortest days of the year at the winter solstice. The Sun's angle relative to Earth's equator changes so gradually close to the solstices that, without instruments, the shift is difficult to perceive for about 10 days. This is the origin of the word solstice, which means 'solar standstill.' This slow shift means that daylight on June 20 is only about 2 seconds longer than on June 21, at mid-northern latitudes in the United States. It will be about a week before there's more than a minute change to the calculated amount of daylight. Even that's an approximation — Earth's atmosphere bends light over the horizon by different amounts depending on weather, which can introduce changes of more than a minute to sunrise and sunset times. Monuments at Stonehenge in England, Karnak in Egypt, and Chankillo in Peru reveal that people around the world have taken note of the Sun's northern and southern travels for more than 5,000 years. From Stonehenge's circle of standing stones, the Sun will rise directly over an ancient avenue leading away to the northeast on the solstice. We know little about the people who built Stonehenge, or why they went to such great effort to construct it, moving multi-ton stones from rock outcrops as far as 140 miles away. All this to mark the spot on the horizon where the Sun returns each year to rest for a while before moving south again. Perhaps they, like us, celebrated this signal of the coming change of seasons. Stephen Schneider is a Professor of Astronomy at UMass Amherst.
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Scientists issue urgent warning over drinking bottled BEER – as they discover a single glass bottle contains 50 times more dangerous microplastics than a plastic bottle
With temperatures set to hit 32°C in parts of the UK this weekend, many Brits will be looking forward to cracking open a cold beer in the sunshine. But a new study might make you think twice before reaching for your favourite bottle. Scientists fom the French food safety agency, ANSES, have discovered that drinks sold in glass bottles - including water, beer, and wine - contain more microplastics than those in plastic bottles. Initially, the researchers were baffled with this finding. However, they soon worked out that the microplastic particles were getting into the drinks through the paint on the outside of the bottles. 'We expected the opposite result,' Iseline Chaib, who conducted the research, told AFP. 'We then noticed that in the glass, the particles emerging from the samples were the same shape, color and polymer composition—so therefore the same plastic—as the paint on the outside of the caps that seal the glass bottles.' Worryingly, the long-term effects of these microplastics on human health remain unclear. Initially, the researchers were baffled with this finding. However, they soon worked out that the microplastic particles were getting into the drinks through the paint on the outside of the bottles. For the study, the team set out to evaluate the levels of microplastics in various popular drinks sold in France. Their analysis revealed an average of around 100 microplastic particles per litre in glass bottles of soft drinks, lemonade, iced tea, and beer. That was between five and 50 times higher than the rate detected in plastic bottles or metal cans. The researchers inspected the glass bottles, and discovered small scratches on the caps, likely created due to friction between the caps when they were stored. For water, both flat and sparkling, the amount of microplastic was relatively low in all cases, ranging from 4.5 particles per liter in glass bottles to 1.6 particles in plastic. Wine drinkers will also be relieved to hear that wine contained few microplastics — even glass bottles with caps. Soft drinks however contained around 30 microplastics per liter, while lemonade had 40 microplastics per liter. Beer was the worst offender, with a whopping 60 microplastics per liter. As it stands, the researchers do not know whether these microplastics represent a health risk. However, researchers are increasingly concerned about the capacity of such particles to be internalised within cells causing alterations in cellular function, particularly when interacting with organs in children and causing definitive alterations in adult life. There is a growing body of evidence that plastics could play a key role in early-onset cancer genesis, where healthy cells turn cancerous. Last year, a study found cancer cells in the gut spread at an accelerated rate after contact with microplastics. Experts have also raised the alarm about a potential between microplastics and reproductive health. Scientists warned in June that they found tiny plastic particles in men's sperm. Thankfully, the researchers say that drink manufacturers could easily reduce the amount of microplastics shed by bottle caps. As part of the study, the team tested a cleaning method involving blowing the caps with air, then rinsing them with water and alcohol. This was found to reduce microplastic contamination by 60 per cent. WHAT CAN MICROPLASTICS DO TO THE HUMAN BODY IF THEY END UP IN OUR FOOD SUPPLY? According to an article published in the International Journal of Environmental Research and Public Health, our understanding of the potential human health effects from exposure to microplastics 'constitutes major knowledge gaps.' Humans can be exposed to plastic particles via consumption of seafood and terrestrial food products, drinking water and via the air. However, the level of human exposure, chronic toxic effect concentrations and underlying mechanisms by which microplastics elicit effects are still not well understood enough in order to make a full assessment of the risks to humans. According to Rachel Adams, a senior lecturer in Biomedical Science at Cardiff Metropolitan University, ingesting microplastics could cause a number of potentially harmful effects, such as: Inflammation: when inflammation occurs, the body's white blood cells and the substances they produce protect us from infection. This normally protective immune system can cause damage to tissues. An immune response to anything recognised as 'foreign' to the body: immune responses such as these can cause damage to the body. Becoming carriers for other toxins that enter the body: microplastics generally repel water and will bind to toxins that don't dissolve, so microplastics can bind to compounds containing toxic metals such as mercury, and organic pollutants such as some pesticides and chemicals called dioxins, which are known to causes cancer, as well as reproductive and developmental problems. If these microplastics enter the body, toxins can accumulate in fatty tissues.
