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NASA is preparing a mission to deliberately smash a spacecraft into an asteroid — a test run should humanity ever need to stop a giant space rock from wiping out life on Earth.

It may sound like science fiction, but the DART (Double Asteroid Redirection Test) is a real proof-of-concept experiment, blasting off at 10:21pm Pacific Time Tuesday (11:51am IST Wednesday) aboard a SpaceX rocket from Vandenberg Space Force Base in California.

The goal is to slightly alter the trajectory of Dimorphos, a “moonlet” around 525 feet (160 metres, or two Statues of Liberty) wide that circles a much larger asteroid called Didymos (2,500 feet in diameter). The pair orbit the Sun together.

Impact should take place in the fall of 2022, when the binary asteroid system is 6.8 million miles (11 million kilometres) from Earth, almost the nearest point they ever get.

“What we’re trying to learn is how to deflect a threat,” NASA’s top scientist Thomas Zuburchen said of the $330 million (roughly Rs. 2,460 crore) project, the first of its kind.

To be clear, the asteroids in question pose no threat to our planet.

But they belong to a class of bodies known as Near-Earth Objects (NEOs), which approach within 30 million miles.

NASA’s Planetary Defense Coordination Office is most interested in those larger than 460 feet in size, which have the potential to level entire cities or regions with many times the energy of average nuclear bombs.

There are 10,000 known near-Earth asteroids 460 feet in size or greater, but none has a significant chance to hit in the next 100 years. One major caveat: scientists think there are still 15,000 more such objects waiting to be discovered.

15,000mph kick

Planetary scientists can create miniature impacts in labs and use the results to create sophisticated models about how to divert an asteroid — but models are always inferior to real world tests.

Scientists say the Didymos-Dimorphos system is an “ideal natural laboratory,” because Earth-based telescopes can easily measure the brightness variation of the pair and judge the time it takes the moonlet to orbit its big brother.

Since the current orbit period is known, the change will reveal the effect of the impact, scheduled to occur between September 26 and October 1, 2022.

What’s more, since the asteroids’ orbit never intersects our planet, they are thought safer to study.

The DART probe, which is a box the size of a large fridge with limousine-sized solar panels on either side, will slam into Dimorphos at just over 15,000 miles an hour.

Andy Rivkin, DART investigation team lead, said that the current orbital period is 11 hours and 55 minutes, and the team expects the kick will shave around 10 minutes off that time.

There is some uncertainty about how much energy will be transferred by the impact, because the moonlet’s internal composition and porosity are not known.

The more debris that’s generated, the more push will be imparted on Dimorphos.

“Every time we show up at an asteroid, we find stuff we don’t expect,” said Rivkin.

The DART spacecraft also contains sophisticated instruments for navigation and imaging, including the Italian Space Agency’s Light Italian CubeSat for Imaging of Asteroids (LICIACube) to watch the crash and its after-effects.

“The CubeSat is going to give us, we hope, the shot, the most spectacular image of DART’s impact and the ejecta plume coming off the asteroid. That will be a truly historic, spectacular image,” said Tom Statler, DART program scientist.

Nuclear blasts

The so-called “kinetic impactor” method isn’t the only way to divert an asteroid, but it is the only technique ready to deploy with current technology.

Others that have been hypothesised include flying a spacecraft close by to impart a small gravitational force.

Another is detonating a nuclear blast close by — but not on the object itself, as in the films Armageddon and Deep Impact — which would probably create many more perilous objects.

Scientists estimate 460-foot asteroids strike once every 20,000 years.

Asteroids that are six miles or wider — such as the one that struck 66 million years ago and led to the extinction of most life on Earth, including the dinosaurs — occur around every 100-200 million years.


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NASA Astronaut Sunita Williams Refutes Health Concerns Amid ISS Mission

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NASA Astronaut Sunita Williams Refutes Health Concerns Amid ISS Mission

NASA astronaut Sunita Williams has recently addressed speculations surrounding her health condition while on the International Space Station (ISS), discarding recent claims made by media outlets regarding her wellbeing. In response to reports that suggested she appeared “gaunt” due to an extended stay on the ISS, Williams clarified her status during a video interview on November 12, explaining that her weight has remained unchanged since her arrival in orbit.

Routine Exercise and Physical Adaptations

Williams, who commands Expedition 72 aboard the ISS, responded to health concerns publicly, indicating that any changes in her physical appearance are the result of rigorous exercise routines rather than health deterioration. Like all astronauts on extended missions, she has been following an intense workout regimen designed to counteract the muscle and bone density loss commonly associated with prolonged microgravity exposure. Williams stated that her routine includes running on a treadmill, riding an exercise bike and lifting weights. It is a form of exercise that has led to increased muscle mass, particularly in her thighs and glutes, while her overall weight remains consistent.

NASA’s Statement on Crew Health

NASA had previously denied the reports, emphasising that Williams and her fellow crew members, including NASA astronaut Butch Wilmore, are in good health. Williams and Wilmore, who arrived at the ISS on June 6 aboard Boeing’s Starliner capsule, were initially scheduled for a ten-day mission under the Crew Flight Test programme. Technical issues with Starliner’s thrusters led NASA to extend their stay on the ISS until early 2025, when they are expected to return with SpaceX’s Crew-9 mission astronauts.

Current ISS Crew Status

The current ISS team, led by Williams, includes three NASA astronauts and three Russian cosmonauts, all working collaboratively despite recent media scrutiny. Williams assured viewers that her health and morale remain robust as the crew carries out essential research and maintenance tasks on the orbiting laboratory showing NASA’s confidence in their well-being during extended missions.

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Math reveals secrets to gaining height on a half-pipe

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Math reveals secrets to gaining height on a half-pipe

A recent study reveals how skateboarders can use mathematical insights to increase their speed and height on half-pipes. Florian Kogelbauer, a mathematician from ETH Zurich, and his research team have examined how specific movements impact a skateboarder’s performance on U-shaped ramps. By alternating between crouching and standing in certain areas, skaters can generate extra momentum, leading to higher jumps and faster speeds. This research, published in Physical Review Research, could lead to more efficient techniques for skaters aiming to improve their skills.

Modelling Momentum on Half-Pipes

The research was published in American Physical Society Journal. The technique of “pumping,” or alternating between crouching and standing, is essential for building speed on half-pipes. Kogelbauer’s team created a model to show how the body’s centre of mass affects movement on a ramp, much like the mechanics of a swing. In their calculations, they found that crouching while moving downhill and standing while moving uphill helps skaters gain height more effectively. This rhythm, the team suggests, could help skaters reach higher elevations on the ramp in fewer motions.

Testing the Theory with Real Skaters

To test the model’s validity, researchers observed two skateboarders as they navigated a half-pipe. They were asked to reach a specific height as quickly as possible. Video analysis revealed that the more experienced skater naturally followed the model’s suggested pattern, reaching the target height with fewer motions. The less experienced skater, who did not follow the pattern as precisely, required more time to reach the same height. This contrast suggests that experienced skaters intuitively apply these principles for better performance.

Broader Applications Beyond Skateboarding

According to Sorina Lupu, an engineer at the California Institute of Technology, this simplified model may also have applications in robotics. By demonstrating how minimal adjustments in body position can impact speed and height, this study offers insights that could make robotic movement more efficient. For engineers, this research indicates that straightforward models of human movement could be used to enhance robotic performance, providing an alternative to complex machine-learning models often used in robotics.

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Global Fossil CO2 Emissions Hit Record in 2024

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Global Fossil CO2 Emissions Hit Record in 2024

Global carbon emissions from fossil fuel combustion have reached an unprecedented peak in 2024, with the Global Carbon Project reporting a projected 37.4 billion tonnes of fossil CO2 emissions, a 0.8% increase from 2023. The report underscores an urgent call for emissions reduction as the world’s annual output of CO2 from fossil fuels and land-use changes collectively approaches 41.6 billion tonnes. Despite increased efforts to mitigate climate impacts, there are no clear signs of a peak in global fossil CO2 emissions, heightening the risk of surpassing critical climate thresholds.

Sector-Specific Emissions and Regional Insights

As per a report by University of Exeter, emissions from fossil fuels, including coal, oil, and gas, are anticipated to rise in 2024, accounting for 41 percent, 32 percent, and 21 percent of fossil CO2 emissions, respectively. Coal emissions are expected to increase by 0.2 percent, oil by 0.9 percent, and natural gas by 2.4 percent. On a regional level, China, responsible for 32 percent of global emissions, is projected to see a slight increase of 0.2 percent, while emissions in the United States are expected to fall by 0.6 percent.

The European Union’s emissions are forecasted to decrease by 3.8 percent, whereas India, contributing 8 percent of global emissions, is projected to experience a 4.6 percent rise. Emissions from aviation and shipping sectors are also set to increase by 7.8 percent this year, though they remain below pre-pandemic levels.

Carbon Budget and Climate Warnings

According to Professor Pierre Friedlingstein from the University of Exeter, who led the study, the absence of a peak in fossil CO2 emissions further reduces the remaining carbon budget needed to keep warming below the Paris Agreement’s 1.5-degree Celsius target. At the current emission rate, a 50 percent probability exists of surpassing this threshold within the next six years. Meanwhile, Professor Corinne Le Quéré of the University of East Anglia acknowledged ongoing efforts in renewable energy deployment and reduced deforestation but stressed that substantial emissions reductions are still essential.

Urgency for Accelerated Action

The report emphasises that while some nations demonstrate progress in emissions reduction, these efforts have not been sufficient to reverse the overall global trend. Dr Glen Peters from the CICERO Center for International Climate Research noted that global climate action remains “a collective challenge,” with gradual declines in emissions in certain regions counterbalanced by increases elsewhere.

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