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Look up tonight! The Lyrid meteor shower is reaching its peak! – The Weather Network

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The first meteor shower of Spring, the April Lyrids, are definitely a sight to see.

Timed perfectly on the night of April 21-22, so that the peak of the shower happens the night before the New Moon, there will be no competing sources of light in the sky.

The radiant of the Lyrid meteor shower, at midnight on the night of April 21-22. Credit: Stellarium/Scott Sutherland

The ‘radiant’ of this meteor shower – the point in the sky where the meteors appear to originate – rises in the east as the Sun sets on April 21, and it tracks across the night sky towards dawn.

The absolute ideal time to watch is in the hours after midnight, when the sky is reaching its darkest, and the radiant is high up in the sky. If your sky is reasonably free of clouds, be sure to get away from city light pollution to get the best view!

Lyrid-2020-NATCloudCover

Lyrid meteors originate from a stream of dusty, icy meteoroid debris left behind by Comet C/1861 G1 Thatcher. The comet itself is currently billions of kilometres away, out beyond the orbit of Pluto, and will not be seen again until the year 2276. Still, each year we receive a reminder of its existence, as Earth passes through the near constant stream of tiny meteoroids strung out along the comet’s path. Each year in April, this shows up as streaks of light across the sky, peaking around April 22.

Comet-Thatcher-Path-NASA-CNEOSThis plot shows the path of Comet Thatcher through the solar system. Now, on April 21-22, Earth is intersecting with that path. As the inset shows, at this time, the comet itself is over 16 billion kilometres away, out beyond the orbit of Pluto. Credit: NASA CNEOS/Scott Sutherland

Related: Want to find a meteorite? Expert Geoff Notkin tells us how!

METEOR? METEOROID? METEORITE?

These bright streaks are known as ‘meteors’, and they occur as the meteoroids are swept up and plunge through Earth’s upper atmosphere. Travelling at around 100,000 km/h, a meteoroid compresses the air in its path until that air glows white-hot. A meteor flash typically lasts but a second (or less), but the larger a meteoroid is, the brighter and longer-lived its meteor will be. This is how we get fireballs, and even explosive ‘bolides’ for the largest meteoroids. The meteor winks out either when the meteorid is vapourized, or when the ‘push-back’ from the atmosphere slows the meteoroid down to the point where it can’t compress the air any more.

The stream of meteoroids from Comet Thatcher tends to be relatively sparse. Thus, even at the meteor shower’s peak, the Lyrids only deliver around 20 meteors per hour. Most viewers only see about half that number.

Embedded within the stream, however, are some larger meteoroids, and when those hit the atmosphere, bright fireballs add to the show!

Some fireballs and bolides can actually leave behind bits of the meteoroid that fall to Earth. When these are found on the ground, they are called meteorites.

Related: Got your hands on a space rock? Here’s how to know for sure

COMET & ASTEROID SCARES

In recent weeks, there has been a lot of overblown doomsday hype about possible threats from asteroids and comets.

To state this clearly: There are no threats to Earth from asteroids or comets, and any stories saying differently are wrong, or are outright misinformation. Also, this meteor shower has nothing to do with any threat to Earth. There are multiple meteor showers each year, and they are events to be enjoyed, rather than omens to be feared.

One particular target for this doomsday nonsense is asteroid 52768 (1998 OR2), which is passing by Earth on April 29, 2020.

Asteroid-52768(1998 OR2)-flyby-April292020The orbit of 52768 (1998 OR2), as of April 29, 2020. The inset view shows the asteroid safely positioned far beyond the orbit of the Moon during its closest pass. Credit: NASA CNEOS/Scott Sutherland

These stories have originated from various ‘tabloid’ news sources around the world. With flashy headlines proclaiming “NASA Warns” and using phrases like “Approaching Earth”, they heavily imply that the space agency is issuing alerts about impending impacts with Earth.

Nothing could be farther from the truth, however.

Asteroid 52768 (1998 OR2) was discovered in 1998, and astronomers have logged over 3,500 observations of it, some going back as far as 1987. With that much information at their fingertips, scientists have locked down the orbit of this object.

The main reason these stories seem to be hyping this fly, apparently, is due to the asteroid’s size. 52768 (1998 OR2) is estimated at being around 2.5 kilometres wide. Admittedly, that is significant, and it would be very dangerous if anything like that struck the planet.

As it passes Earth on April 29, however, 52768 (1998 OR2) will be very far away – over 6.3 million kilometres at its closest distance. For reference, that is 16.4 times farther away than the Moon.

Watch below: NASA scientist Kelly Fast, with the Planetary Defense Coordination Office, shows us exactly why there’s no worry about this asteroid!

We now know, with 100 per cent certainty, that 52768 (1998 OR2) is no threat to Earth, either now or at any time in the future.

In fact, the asteroid does not even appear on NASA’s list of ‘potentially hazardous asteroids’ that have any chance of striking us. Some asteroids have earned a place on that list even for having an impact chance that ranks as one chance in ten billion, for a date over 100 years from now. 52768 (1998 OR2) is not on that list now, nor has it ever been (some asteroids live on the list for awhile, and then are removed when further observations demonstrate it is no threat).

Remarkably, the Arecibo Radio Observatory team, operating out of Puerto Rico, captured radar images of 52768 (1998 OR2) over the weekend, by bouncing radio waves off the asteroid’s surface.

Now, as always, NASA states that there are no known asteroid threats for the next 100 years (or more).

Sources: NASA CNEOS | Space Weather | NASA CNEOS | With files from The Weather Network

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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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