Category: 7. Science

Saturn’s largest moon Titan lies well east of Saturn this morning, while several other, smaller satellites cluster closer to the rings.

Saturn still stands out in the early-morning sky as a bright, 1st-magnitude point of light in southwestern Pisces. Two hours before sunrise, the ringed planet is roughly 50° high in the south and offers an easy stepping-stone to Neptune, which lies 1° north of Saturn — close enough to catch both worlds in a single field of view through your telescope. Neptune is invisible to the naked eye but will appear under magnification, shining at magnitude 7.7 and showing off a tiny, bluish-gray, 2”-wide disk. 

Saturn is far more impressive, not only much brighter but also appearing much larger, with a disk 18” across and rings that stretch 42” from end to end. Its brightest moon, mid-8th-magnitude Titan, lies some 2.8’ east of the planet. Titan will reach its greatest eastern elongation tomorrow morning just after 7:30 A.M. EDT, when it will stand a bit more than 3’ due east of Saturn.

This morning several other fainter moons are visible as well, clustered much closer to the planet. Tenth-magnitude Tethys, Rhea, and Dione are all visible around 5 A.M. EDT; Rhea is about 1.3’ east of Saturn, while Tethys is just 30” west of the planet and Dione another 30” west of Tethys. 

Sunrise: 5:56 A.M.
Sunset: 8:16 P.M.
Moonrise: 10:59 A.M.
Moonset: 10:44 P.M.
Moon Phase: Waxing crescent (24%)
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40° N 90° W. The Moon’s illumination is given at 12 P.M. local time from the same location.

For a look ahead at more upcoming sky events, check out our full Sky This Week column. 

Imagine looking up on a clear night in April 2029 and, without a telescope, spotting a moving dot streaking across the sky—a cosmic visitor closer than most satellites orbiting above us. Now, you might be wondering, being in 2025 why are we talking about 2029, yes you guessed it right, it’s because of the 99942 Apophis. In the world of planetary science, few asteroids have drawn as much attention as 99942 Apophis. Discovered in the year 2004, this near-Earth object stunned astronomers and the public alike with the early prediction that it could strike Earth in the decades ahead, and if we say exactly when it is going to happen then as per initial observations indicated, a probability of 0.027 (2.7%) that it would hit Earth on Friday, April 13, 2029. However, additional observations provided improved predictions that eliminated the possibility of an impact on Earth in 2029.Let’s decode about 99942 Apophis, before we go to any kind of speculation.Nicknamed after the Egyptian god of chaos and darkness, Apophis quickly became a symbol of doomsday speculation. Also known as the “God of Chaos” Asteroid, it is roughly a potentially hazardous object of 45 meters by 170 meters in size. The asteroid momentarily reached Level 4 on the Torino Scale, a hazard rating used by scientists to communicate impact risk—a record high at the time for any known asteroid. Level 4 implies a “close encounter, meriting attention by astronomers,” which is rare and significant.As per the new data collected by astronomers using both powerful telescopes and radar models, Apophis’s orbit became increasingly precise with marked improvements, lowering the odds of an Earth impact. By 2006, researchers had firmly eliminated the possibility of an impact in 2029, and shortly thereafter, they also dismissed the keyhole scenario for 2036—a situation where a precise alignment during the 2029 flyby might have directed Apophis onto a collision path seven years later—as nearly impossible. The information is still intriguing; however, the speculations are at the odds, indicating fluctuations.If we talk about the listed-out speculations, the another one and the most updated version says simulations conducted in 2013 indicated that the Yarkovsky effect could cause asteroid 99942 Apophis to pass through a “keyhole” during its close approach in 2029, setting it on a trajectory to come near Earth again in 2051. Following that, Apophis might pass through another keyhole leading to a possible Earth impact in 2068. However, the probability of the Yarkovsky effect having precisely the required magnitude to produce this sequence of events was estimated to be only about two in a million. As of now, Apophis has been officially removed from risk lists maintained by NASA and the European Space Agency. There is no predicted impact risk for at least the next 100 years—a scientific consensus reached after 17 years of careful study.However, fear of life is still persistent and people might wonder about what is going to happen on April 13, 2029. Despite the safety assurances, the day will be a historic day in asteroid studies. On this date, Apophis will pass at a distance of roughly 32,000km from Earth’s surface, closer than many satellites and easily visible to the naked eye in millions of locations around the globe.Even though at present times, there’s no potential risk or harm, just imagine what if it hits the earth? While there’s no threat now, it’s worth exploring the kind of damage an Apophis-sized object could cause if it ever did strike. Current models predict an explosion releasing over 1,000 megatons of TNT-equivalent energy—tens to hundreds of times more than the world’s most powerful nuclear weapons. An impact in the ocean would generate enormous tsunamis, while a land strike could devastate a region the size of a major metropolitan area. Instead of a doomsday scenario, Apophis has become one of science’s most watched space objects, with NASA redirecting a spacecraft and international teams planning careful observations during the 2029 flyby.99942 Apophis once symbolized a nightmare scenario a cosmic bullet with Earth in its sights. The asteroid’s encounter will be historic not because of danger, but because it offers humanity a front-row seat to the wonders and challenges of our ever-changing solar system. There is no credible scenario in which Apophis could destroy Earth; however, it is still interesting to unleash the intricacies and probabilities of 99942 Apophis hitting the earth. Only time could tell what is going to happen in the future, leaving behind the speculations.

It’s hard to tell when — and why — our ancestors got down from trees and started walking on two legs. Many early hominins capable of bipedal walking were also well-adapted for climbing, and we lack fossil evidence from a key period when climate change turned forests into open, dry woodland called savannah-mosaic, which might have pushed hominins onto the ground. Now a study on modern chimpanzees could help fill in the gaps. Scientists observing chimpanzees in the Issa Valley, Tanzania have shown that despite living in a savannah-mosaic, they frequently climb trees for valuable food — potentially explaining why early hominins kept their arboreal adaptations.

“For decades it was assumed that bipedalism arose because we came down from the trees and needed to walk across an open savannah,” said Dr Rhianna Drummond-Clarke of the Max Planck Institute for Evolutionary Anthropology, lead author of the article in Frontiers in Ecology and Evolution. “Here we show that safely and effectively navigating the canopy can remain very important for a large, semi-arboreal ape, even in open habitat. Adaptations to arboreal, rather than terrestrial, living may have been key in shaping the early evolution of the human lineage.”

Habitats and hunger

Issa Valley is divided between a small amount of thick forest surrounding riverbanks and open woodland. The chimpanzees forage more in the woodland during the dry season, when it offers more food. Their habitat and diet are comparable to those of some early hominins, which means their behavior might offer insights into those extinct hominins’ lives.

“Our previous research found that, compared to chimpanzees living in forests, Issa Valley chimpanzees spent just as much time moving in the trees,” said Drummond-Clarke. “We wanted to test if something about how they foraged could explain their unexpectedly high arboreality. Savannah-mosaics are characterized by more sparsely distributed trees, so we hypothesized that adapting behavior to forage efficiently in a tree would be especially beneficial when the next tree is further away.”

Researchers monitored the adults of the Issa community during the dry season, watching how they foraged in trees and what they ate there. The size, height, and shape of the trees were recorded, as well as the number and size of branches.

Issa chimpanzees mostly ate fruit, followed by leaves and flowers — foods found at the ends of branches, so the chimpanzees needed to be capable climbers to reach them safely. They spent longer foraging in trees that were larger and offered more food. The longest foraging sessions, and the most specialized behaviors to navigate thinner terminal branches, were seen in trees with large open crowns offering lots of food: perhaps abundant food justified the extra time and effort. A similar trade-off between the nutritional benefits of specific foods and the effort of acquiring them could also explain why chimpanzees spent longer in trees while eating nutritionally-rich, hard-to-access seeds.

Fast food

Because they are relatively large, chimpanzees move within trees not by climbing on thin branches but by hanging under them, or standing upright and holding on to nearby branches with their hands. Although these ‘safe’ behaviors are traditionally associated with foraging in dense forest, these findings show they’re also important for chimpanzees foraging in a savannah-mosaic.

“We suggest our bipedal gait continued to evolve in the trees even after the shift to an open habitat,” said Drummond-Clarke. “Observational studies of great apes demonstrate they can walk on the ground for a few steps, but most often use bipedalism in the trees. It’s logical that our early hominin relatives also engaged in this kind of bipedalism, where they can hold onto branches for extra balance. If Issa Valley chimpanzees can be considered suitable models, suspensory and bipedal behaviors were likely vital for a large-bodied, fruit-eating, semi-terrestrial hominin to survive in an open habitat.”

However, the researchers say that we need more fossil evidence and more studies on different aspects of chimpanzee foraging to test this idea.

“This study only looked at foraging behavior during the dry season,” cautioned Drummond-Clarke. “It would be interesting to investigate if these patterns remain during the wet season. Analyses of the nutritional value of foods and overall food availability are also needed to test our hypothesis that a strategy of foraging for longer in large trees on certain foods is energy-efficient in an open habitat.

“Importantly, this is also only one community of chimpanzees. Future studies of other chimpanzees living in such dry, open habitats will be vital to see if these patterns are truly a savannah-mosaic signal or unique to Issa.”

The subjective nature of emotions makes them difficult to study. The high-resolution brain recording methods available for use in animal models can’t be used with people, but at the same time, researchers cannot ask an animal how it is feeling.

“That’s one of the biggest bottlenecks,” says Nicole Rust, professor of psychology at the University of Pennsylvania. “For that reason, emotion research has not been progressing at the same rapid clip as these other brain functions,” such as memory, vision and attention.

But a new cross-species paradigm breaks through the bottleneck, Rust says. An unpleasant sensory experience—puffs of air directed at the eye—elicits an emotional response characterized by activity patterns that linger in higher-order brain areas in both mice and people. The dissociative anesthetic ketamine blocks this activity but does not affect sensory responses to the eye puffs, according to the paper, published in May in the journal Science.

“It’s just a thrilling set of experiments to see a brain-wide pattern of activity that is altered in a state where we know that there is going to be a subjective alteration as well,” says lead investigator Karl Deisseroth, professor of bioengineering, psychiatry and behavioral sciences at Stanford University. “It’s one of those moments where you’re getting a first glimpse at a vast and complex landscape.”

The “setup and the scope are impressive,” but it’s not convincing that the lingering brain state is in fact driven by an emotion, says Ralph Adolphs, professor of psychology, neuroscience and biology at the California Institute of Technology, who was not involved in the study. Instead, the main benefit of the work, he says, “is that it gives us a protocol, an approach to study aspects of emotion” and related states across species, “which is incredibly difficult to set up.”

T

he inspiration for the study came in 2019, Deisseroth says, when his team recorded the brain activity of a person with epilepsy while the person naturally entered a dissociative state, or a separation of emotion from sensory awareness, in the run-up to a seizure. The individual displayed slow oscillations in their retrosplenial cortex, similar to what ketamine induces in mice, the team reported in a resulting 2020 paper.

“It was an n of one—a very interesting n of one,” Deisseroth says. “But then the question was, ‘How can we systematize this?’ We’re not going to get that lucky again, or not likely to. And so we thought, ‘Well, let’s find a way to cause dissociation. Let’s find a way to cause this separation out of the emotional state from sensory awareness,’” and in a way that can be done in both mice and people. To do this, the team reasoned, they would first induce an emotional state in both species using the same stimulus and then separate it from the sensory response using ketamine.

The team selected eye puffs as their stimulus because it is safe, uncomfortable but not painful, and temporally precise, which makes it easier to synchronize with electrical recordings. The team recorded activity across the brain using single-unit Neuropixels probes in mice and surgically implanted electrodes in people with epilepsy who were in the hospital for seizure monitoring.

The eye puffs promptly elicited a reflexive sensory response: Both mice and people quickly blinked their eyes, and event-related potentials peppered most of the brain.

The puffs also evoked an affective response, during which both species closed their eyes for a prolonged period. The participants described the sensation as “annoying” and “very unpleasant.” The mice, after repeated eye puffs, drank less of a liquid reward—the nutritional shake Ensure. After the global, rapid sensory response, slower, reverberating patterns of brain activity unfolded across subsets of the brain, including the frontoparietal and limbic networks. The “persistent timescale” of the activity patterns may be what enables emotions to integrate information from different sources and create a state that guides behavior, Deisseroth says.

An infusion of ketamine abolished this affective state but did not dampen the sensory response: The eye closure stopped but the eye blink remained. Comments from the participants confirmed the distinction between the states. One person reported that after ketamine, the eye puff “was this thing happening to me, but I wasn’t really there paying attention to it.”

The brain dynamics changed in a parallel way. The ketamine did not alter the event potentials in the initial response yet quashed the prolonged activity patterns in the second phase.

This cross-species protocol is “really elegant” and “one of the most exciting parts of the study,” says Meryl Malezieux, a postdoctoral researcher in Nadine Gogolla’s lab at the Max Planck Institute of Psychiatry, who studies heart-brain interactions in emotions but was not involved with this particular study. “Even in basic science, what we do in rodents we want to translate to humans. It’s really hard to design a study—and to have the opportunity, actually—to be able to do something in humans and in rodents at the same time.”

Tracking activity across the entire brain for an extended period of time is also a fantastic approach, says Luiz Pessoa, professor of psychology at the University of Maryland, who was not associated with this research. “I really commend the authors for this,” he says, because the field needs to move beyond only looking at the brain through “snapshots in space and time.”

Y

et some emotion researchers say they aren’t convinced that the state Deisseroth and his colleagues recorded is in fact an emotion.

“There’s nothing possible you can do to say that a mouse is having an emotional state comparable to what a human is having,” says Joseph E. LeDoux, professor of neural science and psychology at New York University, who was not involved in the work. “The fact that a mouse behaviorally responds in a way that a human does, doesn’t mean that the human subjective experience is transferable to the mouse.”

That conundrum is “the whole reason we did this mouse-human bridging study,” Deisseroth says.

On the human side, it’s dubious that blowing puffs of air into someone’s eye is enough to cause an emotional response, Pessoa says. “It’s a very potent stimulus,” but it’s far removed from the complex emotional experiences that color people’s lives.

The investigators “know it was an emotional response—as much as anyone can know it’s an emotional response—because that’s how it was described by the humans experiencing it,” Deisseroth says. “These descriptions are how we work with emotion in the field of psychiatry.”

Additional experiments would bolster the argument that eye puffs can produce an emotion, Adolphs says. These include testing if other negative stimuli—such as an unpleasant image, sound or odor—elicit the same patterns in brain activity, and if conditioning can generate the same brain state without using the eye puffs.

Malezieux says she is convinced that the team captured an emotional state. “This dissociation, to me, shows that these are two separate states,” she explains, and “the second, longer-lasting state is the emotional component.” But she agrees that conditioning experiments would strengthen the findings, although there likely would be insufficient time to complete these experiments with the participants while they are in the hospital for seizure monitoring. Measurements of physiologic signals that change during an emotion, such as heart rate and respiration, would also be a helpful addition, she says, and it would be interesting to see if positive emotions have similar brain dynamics.

Ultimately, the debates surrounding the paper, and the questions the work raises, add to its value, Adolphs says. “If you’re uncomfortable saying that this really amounts to an emotion—as I am—it then forces you to say, ‘Okay, tell me what would be needed. What else do you want?’ And I think that’s really the most useful exercise for the whole field to come up with.”

What can carbon dioxide (CO₂) on Saturn’s moons teach scientists about their formation and evolution? This is what a recent study submitted to The Planetary Science Journal hopes to address as a team of researchers investigated the different types of CO₂ that exist on several of Saturn’s mid-sized moons. This study has the potential to help scientists better understand the existence of CO₂ on planetary bodies and what this could mean for their formation and evolution, and potentially whether they could possess life as we know it.

For the study, the researchers used data obtained from NASA’s powerful James Webb Space Telescope (JWST) to observe and analyze the presence of CO₂ on eight of Saturn’s mid-sized moons, including (in alphabetical order) Dione, Enceladus, Hyperion, Iapetus, Mimas, Phoebe, Rhea, and Tethys. The goal of the study was to ascertain the types of CO₂ on each moon through the wavelength shifts in JWST’s data.

In the end, the researchers identified four types of trapped CO₂ on the moons, with CO₂ on Dione and Rhea being supplied from Saturn’s E-ring. Moving outward, the researchers concluded that CO₂ is produced from organics on Phoebe, which then transfers to the dark regions of Iapetus and Hyperion. Finally, the researchers discovered trapped CO₂ within water ice on Iapetus and Hyperion. To complement these intriguing findings, the researchers note how they could extend to the Galilean moons of Jupiter.

The study notes, “These observations have interesting implications for the icy Galilean satellites and the state of their CO₂ as well. Interpretations for the CO₂ detected on the Galilean satellites are sometimes similar to the interpretations we have made here for the Saturnian satellites, though in some cases the similarity of the interpretation is in spite of large spectral differences.”

This study comes after scientists used JWST data to identify carbon on Europa in 2023 which followed a Hubble Space Telescope study that found carbon on Europa in 2019. Beyond the solar system, JWST has observed CO₂ on several gas giant exoplanets within the HR 8799 system earlier this year.

While CO₂ only comprises approximately 0.04 percent of Earth’s atmosphere, it plays a crucial role in regulating the planet’s temperature and plant life, as plant’s use photosynthesis to convert CO₂ to oxygen. Beyond Earth and in our solar system, CO₂ is found in abundance on Venus and Mars, with CO₂ contributing to the former’s runaway greenhouse effect and both planets are estimated to have approximately 96 percent CO₂ in their respective atmospheres.

While CO₂ is not considered a definitive biosignature, scientists can use its presence to indicate the possibility of biological activity while providing scientists greater insight into a planetary body’s habitability, whether in its atmosphere or on its surface. Despite the moons analyzed for this study are all airless bodies, the presence of CO₂ could provide clues into each of their histories, specifically their formation and evolution and how Saturn’s rings play a role in that, as well.

Going forward, the researchers call for additional research to be conducted on the dark material observed on several of Saturn’s moons, along with laboratory experiments that could shed light on the processes responsible for trapping CO₂.

What new discoveries about Saturn’s moons and CO₂ will researchers make in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

A Chinese research team has developed a “lunar brick-making machine” that can produce bricks from moon soil, bringing the sci-fi vision of “building houses on the moon with local materials” closer to reality.

The in-situ lunar soil 3D printing system, developed by the Deep Space Exploration Laboratory based in Hefei, Anhui province, uses concentrated solar energy to melt and mold lunar soil, the Science and Technology Daily reported on Monday.

According to Yang Honglun, a senior engineer at DSEL, the lunar brick-making machine uses a parabolic reflector to concentrate solar energy. The concentrated energy is then transmitted through a fiber optic bundle.

At the end of this bundle, the solar concentration ratio can exceed 3,000 times the normal intensity. A high-precision optical system then focuses this concentrated sunlight onto a small point, heating it beyond 1,300 C to melt lunar soil.

The bricks produced by the machine are made entirely from in-situ lunar soil resources without any additional additives. Moreover, these lunar soil bricks exhibit high strength and density, making them suitable not only for constructing buildings but also for infrastructure needs such as equipment platforms and road surfaces.

From conceptual design to prototype development, the research team spent about two years to figure out how to overcome multiple technical challenges in the future, such as efficient energy transmission and lunar soil transport.

For example, the mineral composition of lunar soil varies significantly across different regions of the moon. To ensure the machine can adapt to various types of lunar soil, researchers developed multiple simulated lunar soil samples and conducted extensive testing on the machine before finalizing its design.

“Although the lunar brick-making machine has achieved breakthroughs, constructing habitable structures on the moon still requires overcoming other technological barriers,” Yang said.

He explained that under the moon”s extreme conditions, such as high vacuum and low gravity, lunar soil bricks alone cannot support habitat construction.

“The bricks will primarily serve as protective surface layers for habitats. They must be integrated with rigid structural modules and inflatable soft-shell modules to complete the construction of a lunar base,” he added.

He mentioned a series of technological developments, including lunar brick manufacturing, architectural component assembly and the evaluation of building structure, along with operational validation of both the brick-making machine and construction processes under actual lunar surface conditions.

The habitat modules are designed to withstand the air pressure necessary for human occupancy and are also equipped to integrate with the lunar brick-making machine and surface construction robots, creating a complete building system, he added.

China initiated the International Lunar Research Station, a scientific experimental facility consisting of sections on the lunar surface and in lunar orbit. It is projected to be built in two phases: a basic model to be built by 2035 in the lunar south pole region, and an extended model to be built in the 2040s.

As of April this year, 17 countries and international organizations, as well as more than 50 international research institutions, have joined the ILRS.

Chinese scientists have made simulated lunar soil bricks and sent them to China’s space station via the Tianzhou 8 cargo spacecraft that was launched in November 2024.Astronauts aboard the space station are set to conduct space exposure experiments on the bricks to evaluate their mechanical properties, thermal performance and radiation resistance to acquire critical data for future lunar construction.

Xinhua

NASA has selected Barrios Technology, LLC, in Houston to provide technical integration services for the agency’s human space flight programs.

The Mission Technical Integration Contract is a cost-plus-award-fee and cost-plus-incentive fee contract with core and indefinite-delivery/indefinite-quantity requirements. It has a total estimated value of approximately $450 million, and a period of performance beginning Oct. 1, and ending on Sept. 30, 2027, along with four one-year option periods through 2031.

Under the contract, the contractor will provide technical integration and related services for multiple human space flight programs. These services include program, business, configuration and data management, information technology, systems engineering and integration, mission integration, safety and mission assurance, and operations.

Background and Goal: Large-scale, well organized, and open datasets are necessary for primary care–focused artificial intelligence and machine learning (AI/ML) research and development. This article proposes a set of high-level considerations around the data transformation needed to enable the growth of AI/ML applications in primary care.

Key Insights: The authors propose five key considerations for data transformation in primary care: automation of data collection, organization of fragmented data, identification of primary care–specific use cases, integration of AI/ML into human workflows, and surveillance for unintended consequences. The authors further emphasize three factors that will enable each of these efforts to be effective and work cohesively: increased collaboration of the industry and academia AI/ML communities with primary care, increased funding from the private and public sectors, and upgrades to human and data infrastructures.

Why It Matters: Data transformation to advance AI/ML research and implementation in primary care requires cross-sectoral collaborations between government, industry, professional organizations, academia, and frontline primary care.

Data Transformation to Advance AI/ML Research and Implementation in Primary Care

Timothy Tsai, DO, MMCI, et al

Stanford Healthcare AI Applied Research Team, Division of Primary Care and Population Health, Department of Medicine, Stanford University, Stanford, California

TEMPORARY LINK

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The interstellar object 3I/ATLAS was discovered on July 1, 2025. It is expected to arrive at a distance of 53.6 million kilometers from Jupiter on March 16, 2026.

In a new paper that I wrote (accessible here) with the brilliant Adam Hibberd and Adam Crowl, we show that applying a thrust of 2.675 kilometers per second on September 14, 2025 can bring the Juno spacecraft from its orbit around Jupiter to intercept the path of 3I/ATLAS.

The Juno spacecraft, named after the wife and sister of Jupiter in Roman mythology, was launched from Cape Canaveral on August 5, 2011, and entered a polar orbit around Jupiter on July 5, 2016 to conduct scientific measurements of Jupiter’s composition, gravitational field, magnetic field, and polar magnetosphere. Juno was originally planned to be intentionally deorbited into Jupiter’s atmosphere, but has since been approved to continue orbiting.

The close encounter of 3I/ATLAS to Jupiter provides a rare opportunity to shift Juno from its current orbit around Jupiter to intercept the path of 3I/ATLAS at its closest approach to Jupiter. The instruments available on Juno, namely a near- infrared spectrometer, magnetometer, microwave radiometer, gravity science instrument, energetic particle detector, radio and plasma wave sensor, UV spectrograph and visible light camera/telescope, can all be used to probe the nature of 3I/ATLAS from a close distance.

Our analysis exploits the software package known as Optimum Interplanetary Trajectory Software (OITS), developed by Adam Hibberd. OITS solves the Lambert problem for one orbital cycle only: given two times, what are the 2 orbital arcs that connect them? Assuming that the positions at the beginning of the arc and the end of the arc are known, then there are 2 solutions, a short way and a long way. Having the short way and long way solutions, the way with the maximum velocity thrust ∆V is rejected, leaving the lowest ∆V solution. This procedure is conducted iteratively with different trial values of the initial and final times, until OITS has converged on the overall minimum ∆V solution.

Our calculation focuses on an intercept, namely a flyby, since a rendezvous, where the target’s velocity is matched by the spacecraft, is out-of-the- question, owing to the excessively high hyperbolic speed of 3I/ATLAS relative to Jupiter, 65.9 kilometers per second.

Based on this approach, we used OITS for a Juno ∆V application window covering the present as at the time of writing (July 27, 2025) to the possible end of the mission which is currently scheduled to occur in September 2025.

The feasibility of intercepting 3I/ATLAS depends on the current amount of fuel available from the propulsion system of Juno. However, some inferences can be drawn from the total ∆V available at the beginning of the Juno mission. On its interplanetary trajectory, Juno conducted 2 Deep Space Maneuvers, and 1 Jupiter orbital insertion, both of which would have placed a significant demand on the chemical propulsion employed by Juno (Hydrazine and oxidizer nitrogen tetroxide).

The fuel reservoir on Juno allows an overall initial ∆V available of 2.74 kilometers per second, similar to the ∆V of 2.675 kilometers per second required to intercept 3I/ATLAS. However, the similarity of these numbers motivated our paper. This value is similar to the required ∆V for Juno to intercept 3I/ATLAS. Although the engine of Juno was not operated since 2017, the required ∆V might potentially be within Juno’s performance envelope. In that case, Juno would be able to get close to 3I/ATLAS and use its instruments to probe the nature of the interstellar object and any cloud of gas or dust around it.

Our paper shows that applying a thrust of 2.6755 kilometers per second on September 9, 2025, can potentially bring the Juno spacecraft from its orbit around Jupiter to intercept the path of 3I/ATLAS. With Juno’s many instruments, a fly-by can probe the nature of 3I/ATLAS far better than telescopes on Earth. The desired thrust constitutes a Jupiter Oberth Maneuver which requires an application of ∆V only 8 days prior to the originally intended termination date for Juno’s plunge into the atmosphere of Jupiter. Having delivered this thrust to diminish Juno’s altitude, a further ∆V is subsequently delivered, constituting a Jupiter Oberth Maneuver and resulting in an eventual intercept of the target 3I/ATLAS on March 14, 2026. In total, an overall ∆V of 2.1574 + 0.5181 = 2.6755 kilometers per second is utilized.

If doable, this exciting new goal will rejuvenate Juno’s mission and extend its scientific lifespan beyond March 14, 2026.

Small corrections to Juno’s path might be needed if cometary activity 3I/ATLAS will be intensified as it comes closer to the Sun and its non-gravitational acceleration will change its expected trajectory.

Over the coming decade, the Vera C. Rubin Observatory in Chile. Is expected to discover new interstellar objects every few months. A similar approach can be taken with other spacecraft which happen to be close to their paths.

ABOUT THE AUTHOR

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Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024.

As part of her Summer Reading Challenge, Second Lady Usha Vance will host an event for children in grades K-8 on Monday, Aug. 4, at NASA’s Johnson Space Center in Houston. Media are invited.

NASA astronaut Suni Williams will join Ms. Vance to read a space-related book to children and participate in other space-related activities.

Live coverage of the reading will stream about 2:45 p.m. EDT on NASA+. Learn how to watch NASA content through a variety of platforms, including social media.

U.S. media interested in participating in this event must RSVP to NASA Press Secretary Bethany Stevens at: bethany.c.stevens@nasa.gov, as well as Office of the Second Lady Communications Director Nicole Reeves at: nicole.e.reeves@ovp.eop.gov. Requests must be made no later than 1 p.m. EDT on Thursday, July 31. Confirmed media will receive additional details from NASA. The agency’s media accreditation policy is online.

Through her reading challenge, the Second Lady is encouraging youth to seek adventure, imagination, and discovery between the pages of a book. Students interested in participating in the challenge must read 12 books by Friday, Sept. 5. Additional details, including where to download a reading log, and how to submit it to the White House, are available online.

As part of NASA’s Artemis campaign, the agency will send astronauts to the Moon to prepare for future human exploration of Mars, inspiring Golden Age explorers, and ensuring the United States continues to lead in space exploration and discovery.

Learn more about NASA missions online at:

https://www.nasa.gov

-end-

Bethany Stevens / Cheryl Warner
Headquarters, Washington
202-358-1600
bethany.c.stevens@nasa.gov / cheryl.m.warner@nasa.gov