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Watch NASA Launch DART, a Mission to Crash Into an Asteroid – The New York Times

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An early morning liftoff kicks off DART, NASA’s first mission to test a spacecraft that could one day save Earth from a deadly space rock.

NASA is about to launch a spacecraft with one simple mission: Smash into an asteroid at 15,000 miles per hour.

The mission, the Double Asteroid Redirection Test, or DART, leaves Earth early on Wednesday to test whether slamming a spacecraft into an asteroid can nudge it into a different trajectory. Results from the test, if successful, will come in handy if NASA and other space agencies ever need to deflect an asteroid to save Earth and avert a catastrophic impact.

The DART spacecraft is scheduled to lift off atop a SpaceX Falcon 9 rocket on Wednesday at 1:20 a.m. Eastern time (or 10:20 p.m. local time) from the Vandenberg Space Force Base in California.

NASA plans to host a livestream of the launch on its YouTube channel starting at 12:30 a.m. on Wednesday.

If bad weather around the Vandenberg launch site prompts a delay, the next opportunity for liftoff would be about 24 hours later.

NASA is crashing DART into an asteroid to test, for the first time, a method of planetary defense that could one day save a city, or maybe the whole planet, from a catastrophic asteroid impact.

DART “is something of a replay of Bruce Willis’s movie, ‘Armageddon,’ although that was totally fictional,” Bill Nelson, NASA’s administrator, said in an interview.

If all goes as planned with DART, NASA will have a confirmed weapon in its planetary defense arsenal. Should a different asteroid ever wind up on a collision course with Earth, the world’s space agencies would have confidence that an asteroid missile like DART would shoo the space rock away.

NASA/Johns Hopkins/APL

After launching to space, the spacecraft will make nearly one full orbit around the sun before it crosses paths with Dimorphos, a football-field-size asteroid that closely orbits a bigger asteroid, called Didymos, every 11 hours and 55 minutes. Astronomers call those two asteroids a binary system, where one is a mini-moon to the other. Together, the two asteroids make one full orbit around the sun every two years.

Dimorphos poses no threat to Earth, and the mission is essentially target practice. DART’s impact will happen in late September or early October next year, when the binary asteroids are at their closest point to Earth, roughly 6.8 million miles away.

Four hours before impact, the DART spacecraft, formally called a kinetic impactor, will autonomously steer itself straight toward Dimorphos for a head-on collision at 15,000 miles per hour. An onboard camera will capture and send back photos to Earth in real time until 20 seconds before impact. A tiny satellite from the Italian Space Agency, deployed 10 days before the impact, will come as close as 34 miles from the asteroid to snap images every six seconds in the moments before and after DART’s impact.

Telescopes on Earth will fix their lenses on the crash site, showing the two asteroids as tiny dots of reflected sunlight. To measure whether DART’s impact changed Dimorphos’s orbit around Didymos, astronomers will track the time between one flicker of light — which indicates that Dimorphos has passed in front of Didymos — and another, which indicates that Dimorphos has orbited behind Didymos.

If Dimorphos’s orbit around Didymos is extended by at least 73 seconds, DART will have successfully performed its mission. But mission managers expect the impact to lengthen the asteroid’s orbit even more, by about 10 and 20 minutes.

Simply striking hazardous space rocks with a nuclear weapon, like in “Armageddon” and other science fiction disaster films, could create a field of more hazardous space rocks, multiplying the dangers posed to Earth, rather than eliminating them.

Still, a nuclear device, if used the right way, is one of a few conceptual tools within NASA’s planetary defense toolbox.

For any small and distant asteroids that could threaten Earth in the next few decades, a mission like DART “has a pretty good probability of getting the job done,” said Brent Barbee, an aerospace engineer at NASA’s Goddard Space Flight Center.

“But if the asteroid is any bigger than that, or if the warning time is any shorter than that, then that’s where you transition from looking at kinetic impactors to nuclear devices,” Mr. Barbee said.

Astronomers and officials from various space agencies have simulated deflecting an asteroid away from Earth with the force of nuclear blasts.

Other asteroid-destroying simulations have shown that nuclear explosives could be used to annihilate some smaller asteroids as close as two months from impact, while posing little risk to Earth.

“There’s a lot of challenging aspects of a nuclear mission besides just the physics of the device itself, and how the device would interact with the asteroid,” Mr. Barbee said.

Treaties that ban the use of nuclear weapons, and the Outer Space Treaty, the cornerstone set of international space laws signed in the 1960s, prohibit the placement or use of nuclear weapons in space

That suggests that any countries’ emergency use of a nuclear-tipped spacecraft to fend off a killer asteroid would amount to a treaty violation. But that legal predicament could be resolved by an emergency meeting of the United Nations Security Council.

Headlines about asteroids making close passes of our planet are routine. But Earth should be safe from hazardous space rocks for the next century, according to NASA.

The agency maintains a database of near-Earth objects that come within about 28 million miles from Earth. The closest object to whiz by Earth in the next few days will be an asteroid between 50 and 100 feet wide, coming within 511,246 miles on Thanksgiving. (That’s about twice the distance to the moon.)

About 27,000 such objects have been tracked by NASA so far, which is just 40 percent of the total amount the agency is tasked with finding under its Near-Earth Object Observations Program.

NASA also maintains the Sentry Risk Table, which is a separate list of asteroids that have a higher chance of impacting Earth (though the chances remain extremely low). One celebrity on that list is Bennu, a gravelly, acorn-shaped asteroid about the size of a skyscraper. It has a 0.057 percent chance of impacting Earth sometime between the years 2178 and 2290.

NASA sent a spacecraft called OSIRIS-REx to Bennu last year to scoop up a suitcase’s worth of rock samples and bring them back to Earth in September 2023.

Of course, space rocks large and small surprise people on Earth all the time, whether by crash-landing on a Canadian woman’s bed or by shattering windows during atmospheric re-entry over a Russian city.

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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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