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Following Comet Y1 ATLAS: the 'Lost Comet' of Spring – Universe Today

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Got clear skies? If you’re like us, you’ve been putting the recent pandemic-induced exile to productive use, and got out under the nighttime sky. And though 2020 has yet to offer up a good bright ‘Comet of the Century’ to keep us entertained, there have been a steady stream of good binocular comets for northern hemisphere viewers, including C/2017 T2 PanSTARRS and C/2019 Y4 ATLAS. This week, I’d like to turn your attention to another good binocular comet that is currently at its peak: the ‘other’ comet ATLAS, C/2019 Y1 ATLAS.

Discovered by the Asteroid Terrestrial-Last Alert System (ATLAS) based at two geographically separate sites on Haleakala and Mauna Loa, Hawaii on the night of December 16th, 2019, Y1 ATLAS was one of the final comet discoveries of 2019.

The comet is on a 3,500 year path around the Sun on a prograde orbit inclined 73 degrees relative to the ecliptic. When this comet last came through the inner solar system around the 25th century BC, the Great Cheops Pyramid of Giza was still fresh from the builders.

Unfortunately, cosmic bad luck sees Comet Y1 ATLAS visiting us at almost exactly the wrong time of year. Had Y1 Atlas crossed the ecliptic in October, it would have passed just 0.08 Astronomical Units (AU) or 7.4 million miles (12 million miles) from the Earth just exterior to our orbit, and would have put on a fine show. As is often the case with comets, six months earlier or later would’ve made a big difference.

The orbital path of Comet Y1 ATLAS through the inner solar system. Credit: NASA/JPL.

As it stands, Comet Y1 ATLAS just passed perihelion at 0.861 AU (80 million miles/130 million kilometers) from the Sun on March 16th, and currently shines at magnitude +8 in the constellation of Andromeda. March through mid-April sees the comet holding steady about 10 degrees above the northwestern horizon at dusk for mid-northern latitude observers, until it vaults northward towards the north celestial pole, becoming a circumpolar object from late April through May. The comet follows the zero hour line in right ascension right through the end of Spring.

As of writing this, this apparition of the comet seems to be slightly over-performing by about half to a full magnitude or so.

Comet Y1 ATLAS from shortly after discovery on December 20th. Credit: Remanzacco Observatory.

Let’s hope that this trend holds. There is also something else that’s very special about comet Y4 ATLAS: it’s similar orbit suggests that it is a fragment of C/1988 A1 Liller. This may have been the result of a cometary breakup long ago, as C/1996 Q1 Tabur and C/2015 F3 Swan all seem to belong to the same family of objects. This also suggests that Y1 ATLAS is dynamically new, and could produce an outburst of its own.

Here’s the blow-by-blow of celestial dates with destiny for comet Y1 ATLAS in the Spring of 2020:

(note: unless otherwise mentioned, “passes near” in the following text means less than one degree).

Path of the comet through late May across the sky. Credit: Starry Night.

March

27-Photo op: the comet passes between NGC 7662 (the Blue Snowball planetary nebula, at 9 degrees distant), and M31 (the Andromeda Galaxy) at 5 degrees away.

The path of Comet Y1 ATLAS through late April at dusk as seen from latitude 35 degrees north. Credit Starry Night.

April

1-Crosses into the
constellation of Cassiopeia the Queen.

14-Crosses the
galactic equator northward.

26-Crosses into the constellation Cepheus the King.

The projected light-curve of Comet C/2019 Y1 ATLAS. Credit: Seiichi Yoshida’s Weekly Information About Bright Comets.

May

1-Photo-op: Y1 ATLAS groups with two other notable 2020 comets: T2 PanSTARRS (6 degrees distant) and Y4 ATLAS (20 degrees distant).

2-Crosses into Camelopardalis, and passes closest to the North Celestial Pole (NCP) at less than eight degrees.

3-Closest to the Earth at 1.17 AU distant.

9-Crosses into Draco.

13- Crosses into
Ursa Major, and passes 3 degrees from M81/M82.

20-Passes near Duhbe
(Alpha Ursae Majoris).

24-passes Owl Nebula Messier 97.

June

22-Passes into Coma Berenices.

29-Passes near the open cluster Melotte 111.

A negative exposure of Comet Y1 ATLAS from March 23rd. Image credit and copyright: Michael Jäger.

As we enter into July, Comet Y1 ATLAS should drop back below binocular visibility to the sub +10th magnitude range, not to visit the inner solar system again until sometime in the mid-7th millennium AD.

Observing comets with binoculars is as simple as sweeping the suspect field and looking for the fuzzy little ‘star’ that stubbornly refuses to snap into focus. Keep in mind, an +8th magnitude comet can appear visually fainter than an +8th magnitude star, as all those precious photons are ‘smeared’ out over the comet’s apparent surface area.

Comet Y4 ATLAS from March 20th. Image credit and copyright: Michael Jäger.

Also, we’ve been getting lots of queries on Comet C/2019 Y4 ATLAS as of late. Yes, there is mounting excitement as this over-performing comet heads towards perihelion in late May… already, the dusty coma of the comet is an amazing 720,000 kilometers (450,000 miles) across… and that’s while it’s still 1.6 AU from the Sun. Claims, however, that it will become “the brightest comet ever witnessed!” need to be met with extreme skepticism. Yes, it may reach 0 magnitude near perihelion on May 31st… but it will also appear 13 degrees from the Sun on that date, and get swamped in the Sun’s glare. The best bet is to nab the comet near dawn in early May, before it disappears from view for good.

Hopefully, tracking down these comets will pass the time in exile. We could really use a solar outburst, galactic supernovae courtesy of Betelgeuse, or great naked eye comet right about now… just nothing apocalyptic.

-Lead image of Comet C/2019 Y1 ATLAS courtesy of José J. Chambó/Slooh

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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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