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NASA’s Double Asteroid Redirection Test (DART) spacecraft is designed to be a one hit wonder. It will end its days by crashing into an asteroid at 24,000 kilometres per hour on September 26. Launched from Earth in November 2021, DART is about the size of a bus and was created to test and prove our ability to defend Earth from a dangerous asteroid.

Landing a direct hit on a target from 11 million kilometres away isn’t easy. But while this sounds far, the asteroid was actually selected by NASA because it is relatively close to Earth. This will give engineers the opportunity to test the spacecraft’s ability to operate itself in the final stages before the impact, as it crashes autonomously.

The target asteroid is called Dimorphos, a body 163 metres in diameter that’s orbiting a 780 metre-wide asteroid called Didymos. This “binary asteroid system” was chosen because Dimorphos is in orbit around Didymos, which makes it easier to measure the result of the impact due to the resulting change in its orbit. However, the Dimorphos system does not currently pose any risk to the Earth.

Regardless, NASA is attempting nothing less than a full scale planetary defence experiment to change an asteroid’s path. The technique being used is called “kinetic impact”, which alters the orbit of the asteroid by crashing into it. That’s essentially what is known as a safety shot in snooker, but played on a planetary level between the spacecraft (as the cue ball) and the asteroid.

A tiny deflection could be sufficient to prove that this technique can actually change the path of an asteroid on a collision path with the Earth.

But the DART spacecraft is going to be completely blown apart by the collision because it will have an impact equivalent to about three tonnes of TNT. In comparison, the atomic bomb dropped on Hiroshima was equal to 15,000 tonnes of TNT.

So, with this level destruction and the distance involved, how will we be able to see the crash? Luckily, the DART spacecraft is not travelling alone on its quest, it is carrying LICIACube, a shoebox-size mini spacecraft, known as a cubesat, developed by the Italian Space Agency and aerospace engineering company Argotec. This little companion has recently separated from the DART spacecraft and is now travelling on its own to witness the impact at a safe distance of 55km.

Never before has a cubesat operated around asteroids so this provides new potential ways of exploring space in the future. The impact will also be observed from Earth using telescopes. Combined, these methods will enable scientists to confirm whether the operation has been successful.

It might, however, take weeks for LICIACube to send all images back to Earth. This period will be utterly nerve wracking – waiting for good news from a spacecraft is always an emotional time for an engineer.

What happens next? An investigation team will look at the aftermath of the crash. These scientists will aim to measure the changes in Dimorphos’ motion around Didymos by observing its orbital period. This is the time during which Dimorphos passes in front and behind Didymos, which will happen every 12 hours.

Ground telescopes will aim to capture images of the Dimorphos’ eclipse as this happens. To cause a significant enough deflection, DART must create at least a 73-second orbital period change after impact – visible as changes in the frequencies of the eclipses.

These measurements will ultimately determine how effective “kinetic impact” technology is in deflecting a potentially hazardous asteroid – we simply don’t know yet.

This is because we actually know very little of the asteroids’ composition. The great uncertainty around how strong Dimorphosis is has made designing a bullet spacecraft a truly enormous engineering challenge. Based on ground observation, the Didymos system is suspected to be a rubble-pile made up of lots of different rocks, but its internal structure is unknown.

There are also great uncertainties about the outcome of the impact. Material ejected afterwards will contribute to the effects of the crash, providing an additional force. We don’t know whether a crater will be formed by the impact or if the asteroid itself will suffer major deformation, meaning we can’t be sure how much force the collision will unleash.

Future missions Our exploration of the asteroid system does not end with DART. The European Space Agency is set to launch the Hera mission in 2024, arriving at Didymos in early 2027 to take a close look at the remaining impact effects.

By observing the deformations caused by the DART impact on Dimorphos, the Hera spacecraft will gain a better understanding of its composition and formation. Knowledge of the internal properties of objects such as Didymos and Dimorphos will also help us better understand the danger they might pose to Earth in the event of an impact.

Ultimately, the lessons from this mission will help verify the mechanics of a high-velocity impact. While laboratory experiments and computer models can already help validate scientists’ impact predictions, full-scale experiments in space such as DART are the closest we will get to the whole picture. Finding out as much as we can about asteroids will help us understand what force we need to hit them with to deflect them.

The DART mission has led to worldwide cooperation among scientists hoping to address the global issue of planetary defence and, together with my colleagues on the DART investigation team, we aim to analyse the impact effects. My own focus will be on studying the motion of the material that is ejected from the impact.

The spacecraft impact is scheduled for September 26 at 19:14 Eastern Daylight Time (00:14 British Summer Time on September 27). You can follow the impact on NASA TV.


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How NASA Saved a Dying Camera Near Jupiter with Just Heat

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How NASA Saved a Dying Camera Near Jupiter with Just Heat

NASA’s Juno spacecraft, in orbit around Jupiter, had a huge problem when its JunoCam imager started to fail after sitting through the planet’s harsh radiation belts for so many orbits. Designed to only last through the initial few orbits, JunoCam astonishingly endured 34 orbits. Yet by the 47th orbit, the effects of radiation damage became visible, and by the 56th orbit, images were almost illegible. With few alternatives and time slipping away before a close flyby of Jupiter’s volcanic moon Io, engineers made a daring but creative gamble. Employing an annealing process, they sought to resuscitate the imager by warming it up—an experiment that proved successful.

Long-distance fix

According to NASA, JunoCam’s camera resides outside the spacecraft’s radiation-shielded interior and is extremely vulnerable. After several orbits, it started developing damage thought to be caused by a failing voltage regulator. From a distance of hundreds of millions of miles, the mission team implemented a last-ditch repair: annealing. The technique, which subjects materials to heat in order to heal microscopic defects, is poorly understood but has been succeeding in the lab. By heating the camera to 77°F, scientists wished to reorient its silicon-based parts.

At first, efforts were for naught, but only days before the December 2023 flyby of Io, the camera unexpectedly recovered—restoring close-to-original image quality just in time to photograph previously unseen volcanic landscapes.

Radiation Lessons for the Future

Though the camera showed renewed degradation during Juno’s 74th orbit, the successful restoration has led to broader applications. The team has since applied similar annealing strategies to other Juno instruments, helping them withstand harsh conditions longer. Juno’s findings are now informing spacecraft design across the board. “We’re learning how to build radiation-tolerant systems that benefit both defense and commercial satellites,” said Juno’s principal investigator Scott Bolton. These findings would inform future missions, such as those visiting outer planets or working in high-radiation environments near Earth, in the Van Allen belts. Juno’s mission continues to pay dividends with unexpected innovations—a lesson in how a small amount of heat can do wonders.

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NASA’s X-59 Moves Closer to First Flight with Advanced Taxi Tests and Augmented Vision

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NASA’s X-59 Moves Closer to First Flight with Advanced Taxi Tests and Augmented Vision

X-59 of NASA has been designed from the ground to fly at a faster speed of sound without making thunderous sonic booms, which are usually associated with supersonic flight. This 99-foot aircraft, which features a logically elongated design, jettisons the front windscreen and is now heading towards the runway. Pilots can see what is at the front through an augmented reality (AR) enabled closed-circuit camera system, which is termed by NASA as the External Vision System (XVS). NASA took control of an experimental aircraft and performed taxi tests on it during this month.

X-59’s Futuristic Design: Eliminating Sonic Booms with External Vision System

According to As per NASA, the test pilot Nils Larson, during the test, drove the X-59 at the runway by keeping a low speed. This is done to ensure the working of the steering and braking systems of the jet. Lockheed Martina and NASA would perform the taxi tests at high speed, in which the X-59 will move faster to make it to the speed at which it will go for takeoff.

Taxi tests are held at the U.S. Air Force’s Plant 42 facility in Palmdale, California. The contractors and the Air Force utilise the plant for manufacturing and testing the aircraft. Lockheed Martin has developed this aircraft, whose Skunk Works is found in Plant 42.

Taxi Tests at Plant 42: NASA and Lockheed Martin Prepare X-59 for First Flight

Some advanced aircraft of the U.S. military were developed to a certain extent at Plant 42, together with the B-2 Spirit, the F-22 Raptor, and the uncrewed RQ-170 Sentinel spy drone.

SOFIA airborne observatory aircraft, which is a flying telescope called Plant 42, home recently retired. The space shuttle of the agency is the world’s first reusable spacecraft; these were assembled and tested at the facility.

Such taxi tests have started over the last months. NASA worked in collaboration with the Japan Aerospace Exploration Agency for testing a scale model of the X-59 in the supersonic wind tunnel to measure the noise created under the aircraft.

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Unusual Plasma Waves Above Jupiter’s North Pole Can Possibly Be Explained

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Unusual Plasma Waves Above Jupiter’s North Pole Can Possibly Be Explained

In recent observations, NASA’s Juno spacecraft has significantly detected the presence of a variety of plasma waves. The emergence of these waves on Jupiter’s powerful magnetic field is projected to be surprising, as their existence was never marked in the planetary magnetospheres. However, scientists might have come out with an explanation. Furthermore, the current studies have been questioned by scientists surfacing the activity at the North Pole. The article below will exemplify the findings and shed light on the plasmas. 

Uncovering Mystery at Jupiter’s North Pole 

According to a paper published in the Physical Review Letters, the scientists have uncovered the explanation behind the presence of these strange waves. They mainly suspect that the formation of these waves lies behind their evolution as a plasma, which later transforms into something different. 

Inside Jupiter’s Plasmas and Their Variants 

Plasmas are best referred to as the waves that pass through the amalgamation of the charged particles in the planet’s magnetosphere.These plasma waves come across in two forms: One, Langmuir waves, which are high-pitched lights crafted with electrons, while the other, Alfven waves, are slower, formed by ions (heavy particles). 

About Juno’s Findings

As unveiled by the Juno, the findings turned out to be questionable after the scientists noted that in Jupiter’s far northern region, the plasma waves were relatively slower. The magnetic field is about 40 times stronger than the Earth’s, but scientists were shocked to witness the results as the waves were slower. To analyse this further, a team from the University of Minnesota, led by Robert Lysak, identified the possibility of Alfven waves transforming into Langmuir waves. Post studying the data extracted from the Juno, the researchers then began to compare the relationship between the plasma wave frequency and number. 

According to Lysak’s research team, near Jupiter’s north pole, there might be a potential pathway of Alfven waves, which are massive in numbers, transforming into Langmuir waves. Scientists are also predicting that the reason behind evolution might be strong electrons that are shooting upwards at a very high energy. This discovery was made in the year 2016. Considering the current findings, the researchers indicate that Jupiter’s magnetosphere may comprise a new type of plasma wave mode that occurs during high magnetic field strength. 

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