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Millions of people across parts of Mexico, Canada, and the United States watched the rare total solar eclipse on Monday. The path of totality, a tiny area where the Moon completely obscures the Sun, crossed across cities and sent the United States into a frenzy.
However, this year's total solar eclipse was unlike any eclipse we've witnessed in our lifetime – even in 2017. Unlike the 2017 eclipse, the 2024 eclipse was unique in several aspects, from its duration, and path of totality to the expected solar phenomena.
Here's what makes the 2024 eclipse different from the 2017 event.
2024 vs 2017 Eclipse: What was different?
Wider Path of Totality
During this year's eclipse, the moon was almost 8,000 miles closer to Earth than the 2017 event, so the path of totality was wider. The path of totality ranged from 108 to 122 miles wide on Monday compared to a 62 to 71-mile path of totality during the last total solar eclipse.
Dutch-born Christiaan Huygens is probably one of the most famous physicists you've never heard of. His work in the late 17th century straddled both the intangible and tangible realms of our Universe: the nature of light, and the mechanics of moving objects.
Among his many contributions, Huygens proposed a wave theory of light that would give rise to physical optics, which deals with the interference, diffraction, and polarization of light. He also invented the first pendulum clock; the most accurate timekeeper for almost 300 years, right through the Industrial Revolution.
Little has been made of the connections between these two seemingly disparate fields of optics and classical mechanics – until now.
A pair of physicists at the Stevens Institute of Technology in New Jersey have revisited Huygens' seminal work on pendulums, published in 1673, and used his 350-year-old mechanical theorem to uncover some new connections between some of the strangest, and most fundamental, properties of light.
"With this first study we've shown clearly that by applying mechanical concepts, it's possible to understand optical systems in an entirely new way," says physicist Xiaofeng Qian.
Qian and his colleague at the Stevens Institute, Misagh Izadi, considered two properties of light in their calculations: polarization and a form of correlation known as classical, or non-quantum, entanglement.
These two properties reflect the strange duality of light that permeates every pocket of our Universe. In a quantum sense, light – like all forms of matter – can be described as waves rippling through space, but also as discrete particles localized to a single point.
This isn't just a quantum phenomenon, however. In the classical world of cogs and springs and tick-tocking clocks, light waves rise and fall like physical ripples on an intangible ocean, with properties linked to their ever-shifting progress through space.
"We've known for over a century that light sometimes behaves like a wave, and sometimes like a particle, but reconciling those two frameworks has proven extremely difficult," said Qian.
"Our work doesn't solve that problem – but it does show that there are profound connections between wave and particle concepts not just at the quantum level, but at the level of classical light-waves and point-mass systems."
Most commonly considered a quantum phenomenon, entanglement simply describes correlations in the properties of objects. (...)
Qian and Izadi envisaged light as a mechanical system to which Huygens' parallel axis theorem could be applied, and found a "profound" connection: the degree of a light wave's polarization was directly related to the degree of a recently recognized property called vector-space entanglement.
Qian and Izadi's calculations suggest that as one rises, the other falls, enabling the level of entanglement to be inferred directly from the level of polarization, and vice versa.
"Ultimately, this research is helping to simplify the way we understand the world, by allowing us to recognize the intrinsic underlying connections between apparently unrelated physical laws," Qian says.
The study was published in Physical Review Research.
NASA predicts that the recurrent nova T Coronae Borealis will explode sometime in 2024 in a rare event that could be visible to the naked eye.
The star system is located 3,000 light years from Earth.
“Unfortunately, we don’t know the timing of this as well as we know the eclipse,” NASA Meteoroid Environment Office lead Bill Cooke said.
Supernova in NGC 3621 in Hydra. Supernova 2024ggi, discovered a month ago, quickly reached visual magnitude 12.0, stayed there for a couple weeks, and is now beginning to drift down slightly (12.3 as of May 2nd). See the AAVSO's table of recent observations for updates.
NGC 3621, glowing at 10th magnitude, is rather far south at declination –33°. But it crosses the meridian soon after dark. For charts See Bob King's Jupiter meets Uranus in twilight; Supernova erupts in nearby galaxy.
FRIDAY, MAY 3
■ After sunset, use binoculars or a wide-field telescope to try for one last look at Jupiter. It's just above the west-northwest horizon in bright twilight. (Everything else in that area will be completely invisible.) If you succeed, you will be among the few people on Earth to see the giant planet so close to the end of its 2023-24 apparition.
■ On the opposite side of the Sun, low in eastern dawn sky, Saturday morning May 4th finds the waning crescent Moon hangings between Saturn to its upper right and Mars to its left or lower left, as shown below.
THIS WEEK'S PLANET ROUNDUP
Mars and Saturn are in nice view just as dawn begins. The highest and easiest is Saturn, in the southeast. It's magnitude 1.2, fairly modest, but there's nothing else that bright anywhere near it. Its background is dim Aquarius.
Look for Mars far lower left of Saturn, by about four fists at arm's length; it's almost due east. Mars is magnitude 1.1. Don't confuse it with twinkly Alpha Arietis, magnitude 2.0, about a fist to Mars's upper left.
Mercury, Venus, Jupiter, and Uranus remain hidden in the Sun's glare.
Don’t miss Spica’s dramatic disappearance at the Moon’s dark limb. We also check in on the status of current bright comets.
Lunar occultations are commonplace but often involve fainter, telescopic stars. This month we have a wonderful exception. On the night of July 13th, the Moon will cover Virgo's brightest star Spica for much of North and Central America. Sometimes moonlight overwhelms or diminishes the impact of an occultation. Thankfully not this time because the Moon will be in first-quarter phase. Through a small telescope you'll still be able to detect the outline of the earthlit western limb and anticipate the breathtaking moment of Spica's disappearance. Even binoculars will show the star blink out though they may lack sufficient light-gathering power to reveal the limb.
Like a traffic circle without exits the Moon's path is restricted to the ecliptic zone. Round and round the circle it goes, completing one revolution of the sky approximately every month. Because the Moon's orbit is tipped 5.1° relative to the plane of Earth's orbit — which defines the ecliptic — the Moon weaves above and below the plane, so its path over time more resembles a ribbon than a circle. Within that band are four 1st-magnitude stars — Antares, Aldebaran, Regulus, and Spica — that occasionally find themselves squarely in the Moon's path. When it covers one of them, we get to witness a relatively tiny, orbiting ball of rock temporarily "remove" a star several thousand times its size from the sky.
Comet 13P/Olbers, which I reported on here last month, has been trending a little brighter than original expectations. As July opens it glows around magnitude 6.5 and is easily visible in 50-mm binoculars in late twilight. On June 29th in my 10×50s I noted a fuzzy coma about 5′ across with a brighter, more compact center and a wisp of a tail pointing upwards to the northeast. In my 15-inch (38 cm) Dob, 13P's bright head and half-degree tail made a beautiful sight.
The Moon steps smack across Spica as seen from North America. (These scenes are always drawn for an observer at latitude 40° N, longitude 90° W, near the population center of the continent. The Moon's position with respect to Spica will differ a bit depending on where you are. The Moon here is drawn about three times its actual apparent size.)
Look very low in the west as twilight fades for the two inner planets, with Regulus keeping them company. Binoculars will help; the objects' visibility in twilight is exaggerated here,
SATURDAY, JULY 27
■ With the advance of summer the Sagittarius Teapot, sitting in the south left of Scorpius, is tilting to pour from its spout to the right. As it moves westward, the Teapot will tilt farther and farther for the rest of the summer and into early fall — or far into the night if you stay out late.
Face southeast after dark in July, look high, and there's the big, Milky-Way-crossed Summer Triangle. Add Rasalhague to its right, and you've got a pretty good cut diamond standing on its point. Bob King photo
ConfederateSS wrote:--------There are meteor showers in Alpha Capricornids and Delta Aquarius the last few days in July....... ConfederateSS.out!(The Blue and Silver Rebellion)...
SUNDAY, AUGUST 11
■ It's peak Perseid meteor night! And maybe the first of two. The actual peak of the shower is supposed to be from about 13h to 16h UT on the 12th, which is 9 a.m. to noon on the 12th Eastern Daylight Time; 6 to 9 a.m. Pacific Daylight time. That's not long after the ideal Perseid meteor-watching hours before dawn. But who knows, the next night could be just as good or nearly so.
Explanation: This was an unusual night. For one thing, the night sky of August 11 and 12, earlier this week, occurred near the peak of the annual Perseid Meteor Shower. Therefore, meteors streaked across the dark night as small bits cast off from Comet Swift-Tuttle came crashing into the Earth's atmosphere. Even more unusually, for central Germany at least, the night sky glowed purple. The red-blue hue was due to aurora caused by an explosion of particles from the Sun a few days before. This auroral storm was so intense that it was seen as far south as Texas and Italy, in Earth's northern hemisphere. The featured image composite was built from 7 exposures taken over 26 minutes from Ense, Germany. The Perseids occur predictably every August, but auroras visible this far south are more unusual and less predictable.
ConfederateSS wrote: Vote for Kamala
jusplay4fun wrote:If you check in on Jupiter and Mars before dawn this week, compare the yellow-orange tint of Mars to the very similar colors of Aldebaran and, down below, Betelgeuse. To me, Mars looks just the slightest bit paler (less strongly colored) than the two stars. Binoculars help.
Of course, they look so similar for totally different reasons! The stars are blazing, orange-hot gasballs. The surface of Mars is cold, iron-rich rock dust lit by sunlight. Their similarity in brightness right now, as seen from Earth, is a total coincidence. Nowhere in human experience but astronomy are things so different than they appear.SUNDAY, AUGUST 11
■ It's peak Perseid meteor night! And maybe the first of two. The actual peak of the shower is supposed to be from about 13h to 16h UT on the 12th, which is 9 a.m. to noon on the 12th Eastern Daylight Time; 6 to 9 a.m. Pacific Daylight time. That's not long after the ideal Perseid meteor-watching hours before dawn. But who knows, the next night could be just as good or nearly so.
https://skyandtelescope.org/astronomy-news/observing-news/this-weeks-sky-at-a-glance-august-9-18/
It is too cloudy now for me to see any of this in the night sky. That is the realities and disappointments of viewing heavenly events.
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