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In a world first, NASA has crashed a spacecraft into an asteroid in an attempt to push the rocky traveler off its trajectory. The Double Asteroid Redirection Test – or DART – is meant to test one potential approach that could prevent an asteroid from colliding with Earth. David Barnhart is a professor of astronautics at the University of Southern California and director of the Space Engineering Research Center there. He watched NASA’s live stream of the successful mission and explains what is known so far.

1. What do the images show?

The first images, taken by a camera aboard DART, show the double asteroid system of Didymos – about 2,500 feet (780 meters) in diameter – being orbited by the smaller asteroid Dimorphos that is about 525 feet (160 meters) long.

As the targeting algorithm on DART locked onto Dimorphos, the craft adjusted its flight and began heading towards the smaller of the two asteroids. The image taken at 11 seconds before impact and 42 miles (68 kilometers) from Dimorphos shows the asteroid centered in the camera’s field of view. This meant that the targeting algorithm was fairly accurate and the craft would collide right at the center of Dimorphos.

The second-to-last image, taken two seconds before impact shows the rocky surface of Dimorphos, including small shadows. These shadows are interesting because they suggest that the camera aboard the DART spacecraft was seeing Dimorphos directly on but the Sun was at an angle relative to the camera. They imply the DART spacecraft was centred on its trajectory to impact Dimorphos at the moment, but it’s also possible the asteroid was slowly rotating relative to the camera.

The final photo, taken one second before impact, only shows the top slice of an image but this is incredibly exciting. The fact that NASA received only a part of the image implies that the shutter took the picture but DART, traveling at around 14,000 miles per hour (22,500 kilometers per hour) was unable to transmit the complete image before impact.

2. What was supposed to happen?

The point of the DART mission was to test whether it is possible to deflect an asteroid with a kinetic impact – by crashing something into it. NASA used the analogy of a golf cart hitting the side of an Egyptian pyramid to convey the relative difference in size between tiny DART and Dimorphos, the smaller of the two asteroids. Prior to the test, Dimorphos orbited Didymos in roughly 16 hours. NASA expects the impact to shorten Dimorphos’ orbit by about 1 percent or roughly 10 minutes. Though small, if done far enough away from Earth, a nudge like this could potentially deflect a future asteroid headed towards Earth just enough to prevent an impact.

3. What do we know already?

The last bits of data that came from the DART spacecraft right before impact show that it was on course. The fact that the images stopped transmitting after the target point was reached can only mean that the impact was a success.

While there is likely a lot of information to be learned from the images taken by DART, the world will have to wait to learn whether the deflection was also a success. Fifteen days before the impact, DART released a small satellite with a camera that was designed to document the entire impact. The small satellite’s sensors should have taken images and collected information, but given that it doesn’t have a large antenna onboard, the images will be transmitted slowly back to Earth, one by one, over the coming weeks.

4. What does the test mean for planetary defense?

I believe this test was a great proof-of-concept for many technologies that the US government has invested in over the years. And importantly, it proves that it is possible to send a craft to intercept with a minuscule target millions of miles away from Earth. From that standpoint DART has been a great success.

Over the course of the next months and years, researchers will learn just how much deflection the impact caused – and most importantly, whether this type of kinetic impact can actually move a celestial object ever so slightly at a great enough distance to prevent a future asteroid from threatening Earth.


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NASA Data Empowers Global Response to Rising Sea Levels

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NASA Data Empowers Global Response to Rising Sea Levels

Coastal communities around the world are confronting the realities of rising sea levels, which threaten both daily life and essential infrastructure. In response, NASA has collaborated with agencies such as the US Department of Defense, the World Bank, and the United Nations to deliver detailed data on global sea level rise. This information, accessible through NASA’s Earth Information Center, is intended to aid in the preparation and planning for coastal impacts expected through the year 2150.

As per a report by NASA, the centre offers projections of future sea levels and potential regional flooding over the next 30 years. The report highlights that this resource combines data from NASA’s ongoing satellite monitoring with computer modelling of ice sheet dynamics and ocean behaviour, alongside assessments from global authorities like the Intergovernmental Panel on Climate Change. These tools are designed to equip communities with accurate data on which they can base crucial coastal infrastructure and climate resilience plans.

Global Applications of NASA’s Data

Global institutions are using NASA’s sea level data to shape policies and implement adaptive strategies in vulnerable regions, the report mentioned. The World Bank, for example, integrates this information into Climate Risk Profiles for countries most susceptible to rising sea levels. Similarly, the U.S. Department of Defense leverages the data to foresee and mitigate the impacts on its coastal facilities, while the U.S. Department of State uses the information in disaster preparedness and adaptation planning for its international allies, the report further adds.

Selwin Hart, Assistant Secretary-General and special adviser to the United Nations on climate action, described the data as “a critical resource for protecting lives and livelihoods,” emphasising the disparity in impacts between a global warming limit of 1.5 degrees Celsius and current policy projections. This data, he noted, underscores the urgent need for action in vulnerable coastal areas.

Accelerating Rise of Global Sea Levels

The current rate of sea level rise has been shown to increase significantly, with nearly all coastal countries observing heightened sea levels from 1970 to 2023. According to Ben Hamlington, head of NASA’s sea level change team, the rise in sea levels is occurring at an accelerated pace, with average increases nearly doubling over the past three decades. Notably, NASA’s projections indicate that Pacific Island nations will see at least a 15-centimetre rise by 2050, accompanied by a marked increase in high-tide flooding.

The new data platform, as explained by Nadya Vinogradova Shiffer, director of NASA’s ocean physics programme, allows communities worldwide to anticipate future flooding scenarios.

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Ancient pebbles in Israel hint at the earliest form of wheel technology

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Ancient pebbles in Israel hint at the earliest form of wheel technology

Archaeologists in Israel have uncovered doughnut-shaped pebbles that may be among the earliest forms of wheel-like technology. Found at the Nahal Ein Gev II site in northern Israel, these 12,000-year-old limestone pebbles feature central holes and are thought to have been used as spindle whorls—a tool for spinning fibres like flax and wool.

Talia Yashuv, a graduate student and co-author of the study at the Hebrew University of Jerusalem’s Institute of Archaeology, told LiveScience that these ancient artefacts suggest early experimentation with rotational tools that could have laid the foundation for later advancements like the potter’s wheel and the cart wheel. This discovery was published in PLOS One on November 13, offering a glimpse into pre-agricultural technology in the region.

The roughly 100 perforated pebbles were analysed by Yashuv and Leore Grosman, a professor of prehistoric archaeology at the same institute. After scanning each pebble in 3D, the team produced detailed models to assess their potential uses. Most of the pebbles were thought unlikely to serve as fishing weights or beads due to their size and shape, which diverge from artefacts used in similar periods. Instead, the team recreated spindle whorls from the scanned models, which traditional craft expert Yonit Crystal used to spin flax and wool. While the flax was easier to handle, the replicas demonstrated that the pebbles were likely effective as spindle whorls, supporting early textile production, the study noted.

Implications of the Findings

The findings indicate that these spindle whorls could mark a key point in technological evolution, potentially linked to new methods of storage and survival. Alex Joffe, a director at the Association for the Study of the Middle East and Africa and experienced archaeologist, told LiveScience that the possibility that these artefacts could have enabled innovations like bags or fishing lines. Yorke Rowan, an archaeology professor at the University of Chicago, echoed this view, noting that the analysis represents a “critical turning point” in early technology.

A Continuing Debate

While these pebbles may represent one of the earliest uses of wheel-like forms, Carole Cheval, an expert in prehistoric textiles at CEPAM in France, told that the publication that she observed that similar objects have been found in other regions, possibly from earlier periods. This adds another layer to understanding the origins of rotational technology, highlighting the ongoing exploration of ancient human innovation.

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Binar satellites re-enter early due to high solar activity

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Binar satellites re-enter early due to high solar activity

An increase in solar activity has resulted in the early re-entry of three CubeSats from Curtin University’s Binar Space Program. These small satellites, which operated at low Earth orbit, were designed to last for at least six months. However, due to intensified solar conditions, they were destroyed within two months, significantly shortening their scientific mission.

CubeSats like Binar-2, 3 and 4 are particularly vulnerable to space weather impacts because they lack propulsion systems that could counteract the heightened atmospheric drag caused by solar activity. The satellite programme had launched Binar-1 in 2021 during relatively low solar activity, which allowed it to complete a full year in orbit.

The Science Behind Solar Activity

As per a report by The Conversation, solar activity, which includes phenomena such as solar flares, sunspots and solar wind, follows an 11-year cycle driven by the Sun’s magnetic field. Known as “solar cycle 25,” this phase has shown unexpected activity levels, currently over 1.5 times higher than projected. This has impacted not only the Binar satellites but also large-scale operations like the Starlink constellation and the International Space Station, both of which require continuous adjustments to counter increased drag.

Impact of Space Weather on Satellites and Earth

Increased solar activity generates higher levels of ionising radiation and charged particles. This can damage sensitive satellite electronics, disrupt radio communications and increase radiation exposure for astronauts. The intensified solar conditions have also expanded the Earth’s atmosphere outward, leading to increased drag for satellites in low Earth orbit. This affects many smaller satellites, which lack the capability to adjust their altitude.

The recent solar activity has also created more visible auroras, with these atmospheric light displays appearing closer to the equator than seen in decades.

Future Considerations for Space Missions

Despite current challenges, solar activity is expected to decline gradually, reaching a minimum by 2030. This pause may offer more favourable conditions for future missions. In response to current conditions, work has commenced on future Binar missions, which may benefit from a more predictable space weather environment.

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