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How to incinerate the International Space Station – Yahoo Canada Finance

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It took NASA and its partners nearly four dozen trips between 1998 and 2010 to haul the roughly 900,000 pounds worth of various modules into orbit that make up the $100 billion International Space Station. But come the end of this decade, more than 30 years after the first ISS component broke atmosphere, the ISS will reach the end of its venerable service life and be decommissioned in favor of a new, privately-operated cadre of orbital research stations.

The ISS described by module

The problem NASA faces is what to do with the ISS once it’s been officially shuttered, because it’s not like we can just leave it where it is. Without regular shipments of propellant reactant to keep the station on course, the ISS’ orbit would eventually degrade to the point where it’s forward momentum would be insufficient to overcome the effects of atmospheric drag, subsequently plummeting back to Earth. So, rather than wait for the ISS to de-orbit on its own, or leave it in place for the Russians to use as target practice, NASA will instead cast down the station from upon high like Vader did Palpatine.

NASA is no stranger to getting rid of refuse via atmospheric incineration. The space agency has long relied on it in order to dispose of trash, expended launch vehicles, and derelict satellites. Both America’s Skylab and Russia’s Mir space stations were decommissioned in this manner.

Skylab was America’s first space station, for the whole 24 weeks it was in use. When the final 3-astronaut crew departed in early 1974, the station was boosted one last time to 6.8 miles further out in a 289-mile graveyard orbit. It was expected to remain there until the 1980s when increased solar activity from the waxing 11-year solar cycle would eventually drag it down into a fiery reentry. However, astronomers miscalculated the relative strength of that solar event, which pushed up Skylab’s demise to 1979.

In 1978, NASA toyed with the idea of using its soon-to-be-completed Space Shuttle to help boost Skylab into a higher orbit but abandoned the plan when it became clear that the Shuttle wouldn’t be finished in time, given the accelerated reentry timetable. The agency also rejected a proposal to blow the station up with missiles while still in orbit. The station eventually came down on July 11th, 1979, though it didn’t burn up in the atmosphere as quickly as NASA had predicted. This caused some rather large pieces of debris to overshoot the intended Indian Ocean target South-Southeast of South Africa and instead land in Perth, Australia. Despite NASA’s calculations of a 1 in 152 chance that a piece of the lab could hit someone during its de-orbit, no injuries were reported.

Mir’s deorbit went much more smoothly. After 15 years of service it was brought down on March 23rd, 2001, in three stages. First, its orbit was allowed to degrade to an altitude of 140 miles. Then, the Progress M1-5 spacecraft — basically an attachable rocket designed specifically to help deorbit the station — docked with the Mir. It subsequently lit its engine for a little over 22 minutes to precisely put the Mir down over a distant expanse of the Pacific Ocean, east of Fiji.

As for the ISS’ oncoming demise, NASA has a plan — or at least a pretty good idea — for what’s going to happen. “We’ve done a lot of studies,” Kirk Shireman, deputy manager of NASA’s space station program, told Space.com in 2011. “We have found an orbit and a change in velocity that we believe is achievable, and it creates a debris footprint that’s all in water in an unpopulated area.”

According to NASA standards — specifically NASA-STD-8719.14A, Process for Limiting Orbital Debris — the risk of human casualty on the ground is limited to less than 1 in 10,000 (< 0.0001). However, a 1998 study conducted by the ISS Mission Integration Office discovered that an uncontrolled reentry would carry an unacceptable casualty probability of between .024 to .077 (2 in 100 to 8 in 100). A number of controllable decommissioning alternatives have been discussed over the decades, including boosting the ISS farther into orbit in the event of an unexpected evacuation of the station’s crew.

“We’ve been working on plans and update the plans periodically,” Shireman continued. “We don’t want to ever be in a position where we couldn’t safely deorbit the station. It’s been a part of the program from the very beginning.”

Beginning about a year before the planned decommissioning date, NASA will allow the ISS to begin degrading from its normal 240-mile high orbit and send up an uncrewed space vehicle (USV) to dock with the station and help propel it back Earthward. The ultimate crew from the ISS will evacuate just before the station hits an altitude of 115 miles, at which point the attached USV will fire its rockets in a series of deorbital burns to set the station into a capture trajectory over the Pacific Ocean.

NASA has not yet settled on which USV will be employed. A 2019 plan approved by NASA’s safety council, ASAP, relied on Roscosmos to outfit and send up another Progress spacecraft to do what it did for the Mir. However, that vehicle might not actually be available when the ISS is set to come down because Russia’s commitment to the ISS program terminates in 2024. In April of last year, Russian state media began making noise that the country would abandon the station entirely by 2025, potentially stripping parts from this station to reuse in its upcoming national station and leaving the ISS without a reliable way to break orbit. The ESA’s Automated Transfer Vehicle or NASA’s Orion Multi-Purpose Crew Vehicle, though still in development, are both potential alternatives to the Progress.

“NASA is continuing to work with its international partners to ensure a safe deorbit plan of the station and is considering a number of options,” spokeswoman Leah Cheshier told UPI via email in 2021, declining to elaborate on what those options might entail but adding that any deorbiting mission would be “shared by the ISS partnership and is negotiation-sensitive at this time.”

The fall of the ISS is sure to be a spectacle on par with the international hubbub surrounding Skylab’s demise, but is still nearly a decade away and there is plenty of science still left to do. According to the January 2022 International Space Station Transition report:

The ISS is now entering its third and most productive decade of utilization, including research advancement, commercial value, and global partnership. The first decade of ISS was dedicated to assembly, and the second was devoted to research and technology development and learning how to conduct these activities most effectively in space. The third decade is one in which NASA aims to verify exploration and human research technologies to support deep space exploration, continue to return medical and environmental benefits to humanity, continue to demonstrate U.S. leadership in LEO through international partnerships, and lay the groundwork for a commercial future in LEO.

More than half of the experiments performed aboard the ISS nowadays are for non-NASA users, according to the report — including nearly two dozen commercial facilities — “hundreds of experiments from other government agencies, academia, and commercial users to return benefits to people and industry on the ground.” This influx of orbital commercial activity is expected — and being actively encouraged — to further increase over the next few years until humanity can collectively realize Jeff Bezos’ dream of building a low Earth orbit mixed-use business park.

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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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