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Look Up and Watch a 1.1-km Asteroid Fly Past Earth Today – Here's How – SciTechDaily

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This week’s apparition of asteroid 1994 PC1 offers observers a chance to see a space rock moving in real time.

In a slow moving universe, asteroids give us a rare chance to see things moving in real time. We have such a chance coming right up on the evening of Tuesday, January 18th, when 1.1-kilometer asteroid (7482) 1994 PC1 passes 1.23 million miles (1.98 million kilometers) from the Earth. This is about five times the distance from the Earth to the Moon, and just a shade over the distance to the anti-sunward Earth-Sun Lagrange 2 point, soon to be the home of the James Webb Space Telescope.

Fortunately, both the Earth and said space telescope are safe from the asteroid on this pass, and will remain so for centuries in to the foreseeable future. The asteroid was discovered on the night of August 9th, 1994 by astronomer Robert McNaught observing from the Siding Spring Observatory. The Apollo asteroid is an Earth-crosser, with a perihelion interior to our own at 0.9 Astronomical Units (AU) from the Sun, and an aphelion out in the asteroid belt at 1.8 AU, with an orbital period of 572 days. It’s orbital inclination of 33.5 degrees relative to the ecliptic makes it pass far from the Earth on most years.

Asteroid 1994 PC1 Orbit

The orbit of asteroid 1994 PC1. Credit: NASA/JPL

Fun fact: looking back through sky plates, 1994 PC1 actually turns up in images all the way back to 1974.

1994 PC1 is a S-class stony-type asteroid, and is only slightly larger than another well-known NEO asteroid 101955 Bennu the target of <span aria-describedby="tt" class="glossaryLink" data-cmtooltip="

NASA
Established in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. It’s vision is "To discover and expand knowledge for the benefit of humanity."

“>NASA’s Osiris-Rex sample return mission, which returns to Earth with its precious cargo late next year.

This week’s pass is the closest for the asteroid since January 17, 1933 (pre-discovery) at 0.00752 AU, and the closest for the next two centuries, although the pass on January 18, 2105 is nearly as close, at 0.01556 AU.

Asteroid 1994 PC1 Earth Flyby

A closeup of Tueday’s flyby. Credit: NASA/JPL

Hunting the Asteroid

This week’s close approach gives observers a chance to see the asteroid for themselves. At its closest on the night of January 18th at 21:51 Universal Time (UT), 1994 PC1 will be straddling on the Cetus/Pisces border and moving at a blistering 2 degrees an hour (spanning a section of sky four times the size of tonight’s Full Moon, per hour) or 2 arc minutes a minute. That’s fast enough to see the motion of the speedy asteroid versus the starry background after watching it at the eyepiece for just a minute or two. At it’s brightest, 1994 PC1 should flirt with magnitude +9 or so, making it easily visible with a small telescope or perhaps, binoculars.

I remember the thrill of seeing asteroid 4179 Toutatis on its close pass in 2004. That passage was very similar to this week’s, watching as the space rock silently crept across the starry background.

The good news is, you could have started hunting for 1994 PC1 last night: the asteroid is still a respectable +12th magnitude plus on either evening before or after closest approach, January 17th or January 19th. Also, unlike closer passes, parallax versus observer location won’t play too much of a factor in the asteroid’s true position in the sky.

To catch it, you’ll need a telescope capable of precisely pointing at coordinates in right ascension and declination. You can get these ephemerides for your time and location by inputting ‘1994 PC1’ at NASA/JPL Horizons site.

Asteroid 1994 PC1 January 17

The path of the asteroid for the last 12 hours of January 17th. Credit: Starry Night

The night of Monday, January 17th finds asteroid 1994 PC1 low to the south at dusk on the border of the southern hemisphere constellations of Fornax and Eridanus. Tough, though not an impossible target for North American observers.

Asteroid 1994 PC1 January 18

The 24 hour path of asteroid 1994 PC1 for January 18th, in one hour increments. Credit: Starry Night.

The key night of Tuesday, January 18th sees the asteroid making its closest pass by Earth for this century. Standing on the surface of the asteroid Tuesday night, you’d see the Earth as a 22’ half-full disk, slightly smaller than a Full Moon. Though the precise time of closest approach favors Africa and European longitudes, North America also gets a good look at dusk. Another good approach to tracking the asteroid is to know when it’s going to pass near a bright star, stake out the position, and watch at the appropriate time. Once such opportunity occurs in the hours around 21:05 UT Tuesday night, when 1994 PC1 passes 43’ from the +3.8 magnitude star Alrescha (Alpha Piscium).

Asteroid 1994 PC1 Near Alrescha

A close up of the pass near Alrescha (Alpha Piscium) from 21:02 to 21:29 UT. Credit: Starry Night

Wednesday night January 19th sees the asteroid much farther north in the constellation Andromeda. Though now almost 1.7 million miles distant, Wednesday also has the advantage of offering a slim window for viewing after twilight ends, and before the waning gibbous Moon rises.

Asteroid 1994 PC1 January 19

The celestial path of asteroid 1994 PC1 through Wednesday, January 19th. Credit: Starry Night

Clouded out? Astronomer Gianluca Masi and the Virtual Telescope Project has you covered, with a live webcast following 1994 PC1 starting at 20:00 UT on the 18th.

Luckily, asteroid 1994 PC1 won’t offer us the same doomday scenario as the recent comedy Look Up… simply a good show. Good luck and clear skies on your quest to spot asteroid 1994 PC1.

Originally published on Universe Today.

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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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