Connect with us

Published

on

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.


Affiliate links may be automatically generated – see our ethics statement for details.

Continue Reading

Science

China Uses Gravitational Slingshots to Rescue Two Satellites Stuck in Orbit for 123 Days

Published

on

By

China Uses Gravitational Slingshots to Rescue Two Satellites Stuck in Orbit for 123 Days

In a major display of technical ingenuity, China has successfully rescued two satellites—DRO-A and DRO-B—that were stuck in the wrong orbit for 123 days following a launch failure. The satellites, part of China’s distant retrograde orbit (DRO) constellation, were saved using a series of complex gravitational slingshot manoeuvres that turned a near-disaster into a milestone in space navigation. This recovery mission not only preserved critical hardware but also highlighted China’s growing expertise in orbital mechanics, space rescue operations, and deep-space navigation technologies.

Innovative Thinking in critical condition

According to a recent story by CGTN, on March 15, 2024, China launched two satellites that were mounted on a Long March-2C rocket with a Yuanzheng-1S upper stage. While the launch initially appeared to be successful, a malfunction in the upper stage made the satellites tumble and head towards Earth much closer than planned. With limited power and damaged systems, conventional recovery was impossible.

Zhang Hao, a researcher at the Technology and Engineering Center for Space Utilisation (CSU), described the moment the team learned of the issue in an interview with CGTN Digital: “If the satellites were destroyed, that would have been a waste of the years of effort that we put in and the money invested in the mission. It would also be a mental blow to the team.”

CSU engineers divided into two teams—one worked to stabilise the spinning satellites, while Zhang’s team focused on calculating a new trajectory using gravitational assists. “We calculated the best route to move the satellites back on track,” Zhang explained during the interview.

A Gravity-Assisted Comeback

The mission exploited the gravitational pulls of Earth, the Moon, and even the Sun to carefully nudge the satellites into their target DRO positions. The technique is commonly applied in deep space missions, and it needs a minimal amount of fuel, which makes it a feasible way to bypass the fuel shortage. The most critical manoeuvre lasted just 20 minutes but took weeks of preparation. “I got more and more stressed as the clock ticked,” Zhang admitted. “I just kept staring at the screen until it said ‘normal, ‘” he further added.

Now successfully positioned, DRO-A and DRO-B have joined the earlier DRO-L to form a three-satellite constellation. According to CSU researcher Mao Xinyuan, the network will drastically reduce spacecraft positioning times—from days to just a few hours—and support autonomous navigation between Earth and the Moon.

This mission not only salvaged valuable satellites but also demonstrated China’s growing capability in autonomous spaceflight and long-distance orbital engineering.

Continue Reading

Science

SpaceX Launches 23 Starlink Satellites on Falcon 9 Rocket From Cape Canaveral

Published

on

By

SpaceX Launches 23 Starlink Satellites on Falcon 9 Rocket From Cape Canaveral

SpaceX has successfully sent another batch of Starlink satellites into space on Monday, marking its second launch of the day. At 10:34 p.m. EDT (0234 GMT on April 29), a brand-new Falcon 9 rocket carried 23 Starlink broadband satellites, including 13 equipped with direct-to-cell capability, from NASA’s Kennedy Space Centre in Florida. Earlier today, a separate Falcon 9 launched 27 Starlink satellites from Vandenberg Space Force Base in California. The rapid double mission highlights SpaceX’s pace in expanding its Internet constellation, which already stands as the largest of its kind ever deployed.

According to a Space.com report, this launch was significant as it was the first flight for this specific Falcon 9 rocket’s first stage. SpaceX’s boosters see multiple missions, with one record-setting booster achieving 27 flights to date. Despite being brand new, the first stage of the Falcon 9 made a flawless landing approximately eight minutes after launch, gently landing on the “A Shortfall of Gravitas” droneship stationed in the Atlantic Ocean.

Meanwhile, the rocket’s upper stage continued its journey, carrying the 23 Starlink satellites toward low Earth orbit (LEO). The satellites were released about 65 minutes after liftoff, joining — or more aptly, surrounding — the ever-growing constellation of Starlink spacecraft. With tonight’s successful deployment, SpaceX is one step closer to achieving its mission of offering global broadband coverage using thousands of satellites working together.

SpaceX’s 50th Falcon 9 mission of 2025, devoted to growing the Starlink network, is a highlight of the company’s relentless launch cadence, with 33 missions dedicated to the project, which now counts more than 7,200 operating satellites.

SpaceX is still growing out its satellite constellation and refining its launch-and-recovery technology. The fact that the company was able to pull off two successful Starlink missions in a single day demonstrates just how well SpaceX has been able to finesse the balance between reusability with new hardware.

Continue Reading

Science

Amazon Launches 27 Satellites to Start Building Project Kuiper Internet Constellation

Published

on

By

Amazon Launches 27 Satellites to Start Building Project Kuiper Internet Constellation

A United Launch Alliance (ULA) Atlas V rocket has been launched carrying 27 of Amazon’s Project Kuiper broadband spacecraft. The launch took place from Florida’s Cape Canaveral Space Force Station on April 28, 2025, at 7:01 PM EDT (4:31 AM IST). It is reported to be the first of more than 80 launches, which are planned to deploy a megaconstellation for Project Kuiper. The ultimate end goal for Amazon is to provide end-to-end network service, which means routing data both to and from the satellites and from the internet to the satellites and from the satellites to a customer’s terminal antenna. The effort is expected to start covering customers later this year. The remaining 80-plus launches will be performed by Atlas V and its successor, ULA’s new Vulcan Centaur rocket.

According to a Space.com report, the 27 satellites will be initially placed at an altitude of 280 miles (450 kilometres) and will later manoeuvre themselves to their operational height of 392 miles (630 kilometres). Interestingly, reports suggest that Amazon will eventually harbour more than 3,200 satellites. In contrast, SpaceX’s Starlink network already has over 7,200 active broadband satellites. The report further claims that the brand is planning to launch 80 more satellites in the next few months.

Today’s launch used an Atlas V rocket, and the Kuiper fleet rollout will see additional launch missions with more Atlas Vs and Vulcan Centaur rockets.

Amazon has also advanced its satellites with innovative technologies, such as phased array antennas, optical inter-satellite links, updatable software, solar arrays, and efficient propulsion, to create a high-performance service architecture, accessible from any point on Earth.

Amazon’s Kuiper launch seems near following satellite deployment and testing, with an approach to compete with the operational architecture of Starlink by establishing a datalink from the internet down to Earth stations.

Continue Reading

Trending