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Comet NEOWISE: 10 big questions (and answers) about the icy wanderer – Space.com

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See Comet NEOWISE?

(Image credit: NASA/Johns Hopkins APL/Naval Research Lab/Parker Solar Probe/Brendan Gallagher)

If you spot Comet NEOWISE, let us know! Send images and comments to spacephotos@space.com to share your views.

Comet NEOWISE has is delighting skywatchers around the Northern Hemisphere. But what makes this comet so special? 

The comet made its closest approach to the sun on July 3 but, until now, was only visible in the sky before dawn. Now, for keen observers in the Northern Hemisphere, the comet has been getting higher in the evening sky, sparkling northwest below the Big Dipper constellation, according to Joe Masiero, deputy principal investigator of NEOWISE (NASA’s Near-Earth Object Wide-field Infrared Survey Explorer, the NASA space telescope that first spotted the comet).

One of the most fascinating details about Comet NEOWISE is that it won’t return to our skies for another 6,800 years. But that’s not the only thing that makes this icy space rock special. So let’s take a dive into what makes Comet NEOWISE unique — and a little weird.

Related: How to see Comet NEOWISE in the evening sky now 

What is Comet NEOWISE?

Comet NEOWISE, as photographed by Joy Ng, a multimedia producer at NASA’s Goddard Space Flight Center.  (Image credit: Joy Ng)

Officially known as C/2020 F3, Comet NEOWISE is a comet that was discovered on March 27, 2020, by NEOWISE, the asteroid-hunting afterlife of the Wide-field Infrared Survey Explorer (WISE) mission. 

Comets, often nicknamed “cosmic snowballs,” are icy, rocky objects made up of ice, rock and dust. These objects orbit the sun, and as they slip closer to the sun most comets heat up and start streaming two tails, one made of dust and gas and an “ion tail” made of electrically-charged gas molecules, or ions.

Can I see it?

This NASA sky map shows the location of Comet NEOWISE in the evening sky for viewers in the Northern Hemisphere in July 2020. (Image credit: NASA)

Yes! Because it is especially bright, the comet is visible in the night sky with the naked eye. Skywatchers in the Northern Hemisphere can spot the object just after sunset, to the northwest just under the Big Dipper constellation

In fact, the comet is so bright that scientists are “able to get a lot more and better data than we typically do for most comets,” Kramer said. “We’re able to study it with a wide variety of different telescopes, and that’ll allow us to do really interesting studies.”

Related: How to photograph Comet NEOWISE: NASA tips for stargazers

Do I need a telescope? 

No! Because Comet NEOWISE is an especially bright object, it is relatively easy for astronomy enthusiasts to spot it in the night sky with just the naked eye, although binoculars or a small telescope will give you a better view.

“The fact that we can see it is really what makes it unique,” Kramer said. “It’s quite rare for a comet to be bright enough that we can see it with a naked eye or even with just binoculars.”

More: Best telescopes for the money — 2020 reviews and guide

What does it look like in the sky?

Astrophotographer Bill Dunford, a NASA social media specialist at the Jet Propulsion Laboratory in Pasadena, California, captured this view of Comet NEOWISE when it was visible in the predawn sky in early July 2020. (Image credit: NASA/Bill Dunford)

To those spotting the comet with the naked eye, without any tools or instruments like a telescope, it looks like a fuzzy star with a little bit of a tail. You do need to be away from city lights, though.

With binoculars or a small telescope, the comet will be more clear and the tail will be easier to spot. 

Related: Amazing photos of Comet NEOWISE from the Earth and space

How much water is in the comet? 

An unprocessed image from the WISPR instrument on NASA’s Parker Solar Probe shows Comet NEOWISE on July 5, 2020, shortly after its closest approach to the sun. The sun is out of frame to the left. The small black structure near the lower left of the image is caused by a grain of dust resting on the imager’s lens. (Image credit: NASA/Johns Hopkins APL/Naval Research Lab/Parker Solar Probe/Brendan Gallagher)

There is “about 13 million Olympic swimming pools of water,” in Comet NEOWISE, Emily Kramer, a science team co-investigator forNASA’s NEOWISE at NASA’s Jet Propulsion Laboratory, said during a news conference July 15. “So that’s a lot of water.” 

“Most comets are about half water and half dust,” she added.

Does it have a tail?

These false-color images of Comet NEOWISE show the concentration of sodium atoms in the comet’s dusty ion tail. Astronomers created the images using the Planetary Science Institute’s Input/Output facility near Tucson, Arizona. The image on the left shows light reflected off of cometary dust, while the image on the right shows light emitted by sodium atoms. (Image credit: Jeffrey Morgenthaler/Carl Schmidt/Planetary Science Institute)

Comet NEOWISE has two tails that typically accompany every comet.

As a comet nears the sun, it warms up and material pulls away from the surface into a tail. Often, dust is pulled away along with gases from sublimating (going directly from solid to a gas) ice. This dust tail is the sweeping trail seen in most comet images. Comets also have an ion tail made up of ionized gas blown back by the solar wind. 

Researchers studying Comet NEOWISE might actually also have a sodium tail. By observing what they believe to be atomic sodium in the comet’s tail, researchers can glean keen insight into the object’s makeup.

How big is Comet NEOWISE?

An unprocessed image from the WISPR instrument on NASA’s Parker Solar Probe shows Comet NEOWISE on July 5, 2020, shortly after its closest approach to the sun. The sun is out of frame to the left. The small black structure near the lower left of the image is caused by a grain of dust resting on the imager’s lens. (Image credit: NASA/Johns Hopkins APL/Naval Research Lab/Parker Solar Probe/Brendan Gallagher)

Comet NEOWISE is about 3 miles (5 kilometers) in diameter, “which is a reasonably large but roughly average-size comet,” Kramer said.

“It’s rare to see something that’s this bright,” she added. “There are comets that are of this size that we see regularly, but most of them are so from Earth that they don’t get this bright. They’re too far from the sun and the Earth to be able to see them in the way that we’re seeing this Comet NEOWISE.”

How fast is Comet NEOWISE?

Astrophotographer Chris Schur captured this view of Comet NEOWISE F3  from Payson, Arizona before dawn on July 5, 2020. (Image credit: Chris Schur/Chris Schur Astrophotography)

The comet is traveling at about 40 miles per second (that’s about 144,000 mph, or 231,000 km/h). 

Joe Masiero, deputy principal investigator of the NEOWISE mission, said the the comet is moving about twice as fast as the Earth’s speed around the sun. But don’t expect that rapid clip to last.  

Because of the comet’s extremely elliptical orbit, it will slow down as it reaches its farthest point from the sun, then fall back toward the inner solar system and accelerate again when it heads back round the sun. That trip around the sun is over for Comet NEOWISE’s current orbit and it’s moving back to the outer solar system.

“And so as it goes farther from the sun, [it] will be slowing down as it climbs back up that gravity well,” Masiero said.

Will it hit Earth?

Comet NEOWISE as seen from the International Space Station in a photograph shared by Russian cosmonaut Ivan Vagner on July 4, 2020. (Image credit: Ivan Vagner/Roscosmos/NASA)

Have no fear, Comet NEOWISE will not hit Earth. 

“This particular comet has no possibility of impacting the Earth. It crosses the plane of Earth orbit well inside of recovery orbit and almost near the orbit of Mercury, so there’s absolutely no hazard from this comet,” Lindley Johnson, the planetary defense officer and program executive of NASA’s Planetary Defense Coordination Office at NASA Headquarters, said during the news conference. 

The comet orbits the sun every 600 to 700 years, Johnson said. The comet is currently about 70 million miles (111 million kilometers) away from Earth.

Is it from interstellar space?

No, Comet NEOWISE originates in our own solar system. To date, only two interstellar objects have been discovered: ‘Oumuamua and Comet Borisov

“This one we know it’s not Interstellar object. By watching its motion, we can see that it’s bound to the sun’s gravity,” Kramer said. “So it’s coming in very rapidly and then it’s going to go far back out again and then but then should come back in again in about 6,800 years.”

Email Chelsea Gohd at cgohd@space.com or follow her on Twitter @chelsea_gohd. Follow us on Twitter @Spacedotcom and on Facebook.

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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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