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From a Tempest to a Trickle: Prospects for the 2020 Leonid Meteor Shower – Universe Today

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Following the Leonid meteors in 2020.

We witnessed an amazing astronomical spectacle in the early morning skies over the Kuwaiti desert in November 1998. That year, the Leonid meteors put on a spectacular display, topping an estimated 1,000 meteors per hour near sunrise. On most years, however, the Lion whimpers with a few paltry meteors per hour, but once every 33 years or so, the mighty Leonids can roar with an amazing display reaching storm level proportions.

Prospects for the 2020 Leonids

Unfortunately, 2020 is not projected to be such a year, but it’s always worth keeping an eye out during the early morning hours in mid-November. The 2020 peak for the Leonids is expected to arrive on Tuesday, November 17th, at around ~4:00 Universal Time (UT) or 11:00 PM EST (on the 16th). The Moon is a waxing crescent just two days after New at this point, ideal for meteor watching. This also favors the longitude of Europe and Africa at dawn, another plus. The 2020 Zenithal Hourly Rate (ZHR) is expected to hit a moderate 15-20 meteors per hour.

Looking eastward at 3AM local on November 17th. Credit: Stellarium.

The source of the Leonid meteors is periodic comet 55P/Tempel-Tuttle, which is on a 33-year orbit around the Sun. The next major peak for the Leonids is expected for the early 2030s around 2032-33, though circumstances this time around may prove to be less than favorable. It’s worth noting that in the late 1990s we were seeing enhanced rates over several years leading up to 1998, so what we see from the Leonids in the coming decade may be indicative of what we might be in for, come 2032.

The orbit of Comet 55P/Tempel-Tuttle. Credit: NASA/JPL

The Leonids are one of the most notorious of meteor storm producers. On the morning of November 13th, 1833, residents of the U.S. Eastern Seaboard awoke to a truly terrifying sight, as the sky seemed to be awash with meteors, failing like rain. Keep in mind, no one truly knew what meteors actually were until the late 19th century, or how they were related to the dust trails laid down by comets. In fact, the 1833 Leonids are cited as contributing to many of the religious fundamentalist revivals of the 1830s in the U.S… they were that influential.

An 1889 depiction of the 1833 Leonids, based on a first-hand account of Joseph Waggoner. Public Domain/Adolf Vollmy.

Will the Leonids ‘ramp up’ in the coming decade? Keep in mind, the quoted zenithal hourly rate (ZHR) for a given shower is the number you would see with optimal conditions, under a dark, moonless sky with the radiant directly overhead… most of us will see considerably less. Many neophyte observers get excited about the hype leading up to a meteor shower, only to be frustrated by the reality of seeing few if any meteors under light-polluted skies. Be patient, and search out a good dark sky site for best results. Tracing a meteor trail back to the ‘Sickle of Leo’ asterism identifies its membership as a Leonid… otherwise, the meteor may be a background sporadic, or a member of another shower. In November, the Taurids are also active, and the December Geminids are also spooling up. For best results, watch in the early morning hours, when the Earth is meeting the Leonid meteor stream head-on.

The circumstances for the 2020 Leonids. Credit: Orbitron/Dave Dickinson

In recent years, the Leonids have produced an observed peak of 29 (2019), 24 (2018) and 20 (2017) meteors per hour.

Observing a meteor shower is as simple as bundling up, laying back, watching and waiting. We prefer to look about 45 degrees off to one side of the radiant for a shower to see meteors in profile, though honestly, they can appear anywhere in the sky. If you’re observing with a friend, be sure to observe in opposite directions, to double your sky coverage. Also, be sure to keep a set of binoculars handy, as a brilliant fireball can often leave a lingering smoke train that can remain visible for over a minute or so.

You can also ‘hear’ meteors, or more accurately, the ionized reflection crackling in their wake along vacant swaths of the FM radio dial. You hear a similar phenomenon along the FM band during an intense lightning storm. Very occasionally, the radio reflections off of a meteor passage might even briefly bring a distant radio station into focus.

But can you actually hear meteors? This is a true and persistent phenomenon reported over the years by observers… as a kid, I remember hearing a distinct ‘hiss’ accompanying a brilliant Perseid. Now, meteors are just dust grains burning up high in the atmosphere, far from the ground and unable to carry sound to the viewer…plus, unlike the clap of thunder you hear several seconds after you see a flash of lightning, the effect seems to be instantaneous. The culprit appears to be what’s known as electrophonic sound, a local current induction set up off of nearby telephone wires, aluminum siding and even damp dewy grass surrounding the observer during the passage of a meteor.

Our humble meteor imaging rig. Credit: Dave Dickinson

Imaging meteors is also a straightforward affair: a tripod-mounted DSLR camera with a wide-lens covering a good swath of sky will do the trick. Use the manual ‘bulb’ setting to take a series of 1-3 minute exposures, and see what turns up. Be sure to take a series of test exposures first, to get the balance of shutter speed/f-ratio/and ISO exposure just right versus the local sky conditions. Be sure to carefully examine the shots afterwards… nearly every meteor we’ve caught on camera was missed during naked eye observing. I like to use a remote intervalometer to automate the process by setting the camera to record a series of 3-minute exposures, freeing me up to simply sit back and watch the show. Also, keep an extra set of camera batteries handy, preferably in a warm pocket; long exposures and cold November temperatures can drain camera batteries in a hurry.

Finally, don’t forget to keep a count of how many meteors you see, and report your observations to the International Meteor Organization. Amateur visual and radio observations of meteor showers all contribute to our efforts to understand how particular meteor showers evolve, and may even uncover new meteor streams.

Sure, the sky won’t come ablaze with a Leonid meteor storm in 2020, but it’s always worth watching for the stray streaks from the Sickle this coming week, and marveling at what can be.

-Lead image: An all-sky capture of a 2011 Leonid. Credit: NASA/MSFC

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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