adplus-dvertising
Connect with us

Science

The Leonid meteor shower peaks today. Here’s how to see it

Published

 on

Probably the most famous of the annual meteor showers will soon be reaching its maximum: The Leonids. These ultrafast meteors are due to reach their peak on Saturday morning (Nov.  18).

The Leonid meteor shower is known for producing some of the most amazing meteor displays in the annals of astronomy. Most notable are meteor storms such as in 1799, 1833 and 1966 when meteor rates of tens of thousands per hour were observed. More recently, in 1999, 2001 and 2002, lesser Leonid displays of up “only” a few thousand meteors per hour took place.

Unfortunately, the negative impact of those turn-of-the-century Leonid showers, is that many were given the impression that they can expect a similar occurrence of celestial fireworks from the Leonids every year. So, it is important to stress right here at the outset that any suggestion of a spectacular meteor Leonid display this year is, to put it mildly, overly optimistic.

So, should you be expecting a memorable meteor shower show early on Saturday morning, we’re sorry to break this to you, but the 2023 version of the Leonids is more than likely going to be a disappointment, since it probably will be weak and there likely will be long stretches when not a single one will be seen.

Related: Meteor showers 2023: When is the next one?

How to see the Leonids this year

The International Meteor Organization (IMO) forecasts hour rates of 10 to 15 per hour with a peak at around 5:00 UT on Nov. 18. The moon is a waxing crescent and will set before 8:30 p.m. on Friday evening and will pose no interference whatsoever. But whatever forecast you trust, be mindful that even at their very best, Leonids are expected to dart across your line of sight on an average of once every 3 to 6 minutes. And that’s only assuming you have a wide-open view of the entire sky and are blessed with dark, non-light polluted conditions.

Watching a meteor shower is a relatively straightforward pursuit. It consists of lying back, looking up at the sky and waiting. Keep in mind that any local light pollution or obstructions like tall trees or buildings will further reduce your chances of making a meteor sighting.

Leo does not start coming fully into view until the after-midnight hours, so that would be the best time to concentrate on looking for Leonids. As dawn is about to break at around 5 a.m. local time, The Sickle will have climbed more than two-thirds of the way up from the southeast horizon to the point directly overhead (called the zenith).

Also, because the Leonids are moving along in their orbit around the sun in a direction opposite to that of Earth, they slam into our atmosphere nearly head-on, resulting in the fastest meteor velocities possible: 45 miles (72 km) per second. Such speeds tend to produce bright meteors, which leave long-lasting streaks or vapor trains in their wake.

A mighty Leonid fireball can be quite spectacular, but such outstandingly bright meteors are likely to be very few and very far between this year (if any are seen at all).

Astrophotographer Jeff Berkes captured this shot of Leonid meteors over a house in New Jersey in 2012.  (Image credit: Jeff Berkes)

Comet crumbs

The Leonids received their moniker because the shower’s emanation point — from where the meteors seem to fan out — is located within the constellation of Leo, the Lion, from within the backward question mark pattern of stars known as “The Sickle.”

The meteors are caused by periodic Comet Tempel-Tuttle, which sweeps through the inner solar system every 33.3 years. Each time the comet passes closest to the sun it leaves a “river of rubble” in its wake; a dense trail of dusty debris. A meteor storm becomes possible only if Earth were to score a direct hit on a fresh dust trail ejected by the comet over the past couple of centuries.

The “lion’s share” (no pun intended) of comet dust can be found just ahead and trailing behind Tempel-Tuttle. That comet last swept through the inner solar system in 1998. That’s why spectacular meteor showers were seen in 1999, 2001 and 2002, with declining numbers thereafter.

In 2016 Tempel-Tuttle reached aphelion, that point in its orbit, as far from the sun as it can get: 1.84 billion miles (2.96 billion km). Now the comet is on its way back toward the sun and inner solar system and will sweep closest to the sun again in May 2031.

Starry sky over Hora Mountain in Bayingoleng Mongolian Autonomous Prefecture, Northwest China’s Xinjiang Uygur Autonomous Region, on the early morning of Nov. 17, 2021. (Image credit: Xue Bing / Costfoto/Future Publishing via Getty Images)

A meager year in 2023

But it’s also, in the general vicinity of the comet where the heaviest concentrations of meteoroids are as well. In contrast, at the point in the comet’s orbit where we will be passing by on Saturday morning, there’s only a scattering of particles; bits of comet debris that crumbled off the comet’s frozen nucleus perhaps a millennia or two ago.

So, the 2023 Leonids are expected to show lean activity this year. According to a highly regarded Russian expert in meteor shower predictions, Mikhail Maslov, forecasts indicate a “moderate” maximum, which he suggests will stay approximately at the same level (about 15 per hour) during the period from 0:00 to 12:00 UT on Nov. 18.

Canadian meteor forecasters, Margaret Campbell-Brown and Peter Brown, in the 2023 Observer’s Handbook of the Royal Astronomical Society of Canada are a little more optimistic, in suggesting rates of up to 20 per hour with as maximum occurring at 0600 UTC on Nov. 18. That comes to around midnight for eastern and central North America.

A look ahead

The good news is that as Comet Tempel-Tuttle draws closer to the sun, the Leonids are expected to slowly improve. According to Mikhail Maslov, a greater preponderance of bright meteors is possible, especially in 2025. But it will not be until 2033, when both Maslov and another well-known forecaster, Frenchman, Jeremie Vaubaillion, predict hourly rates of several hundred or more possible. But the very best years of the next Leonid cycle will be in 2034 and 2035.

In 2034, debris shed by Tempel-Tuttle from the year 1699 should lead to anywhere from 400 to 1600 Leonids per hour, followed some hours later by another surge of activity from material shed by the comet in 1767; 250 to 1000 Leonids are possible. Finally, in 2035, 300 to 900 Leonids are possible from a dusty meteoroid trail dating back to 1633.

But if you can’t wait until then, here’s some good news: A far more prolific meteor shower is coming our way in less than a month: The December Geminids, now considered to be the best meteor shower of the year, producing over 100 per hour. They are expected to peak on Wednesday night, Dec. 13. Space.com will provide you with all the details as we get closer to that date. So, stay tuned!

If you want to get an up-close look at the stars or planets during the new moon or any other time, our guides to the best telescopes and best binoculars are a great place to start.

And if you’re looking to take photos of the Leonids or the night sky in general, check out our guide on how to photograph meteors and meteor showers, as well as our best cameras for astrophotography and best lenses for astrophotography.

Joe Rao serves as an instructor and guest lecturer at New York’s Hayden Planetarium. He writes about astronomy for Natural History magazine, the Farmers’ Almanac and other publications. 

728x90x4

Source link

Continue Reading

News

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

Published

 on

 

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. ”

___

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

___

Follow Seth Borenstein on Twitter at @borenbears

___

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.

Source link

Continue Reading

Science

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

Published

 on

 

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.

Source link

Continue Reading

News

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

Published

 on

 

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.

Source link

Continue Reading

Trending