This Astronomy Picture of the Day shows a simulated flyover of Pluto's surface, created using images and data from NASA's New Horizons spacecraft. The video highlights the diverse terrain of the dwarf planet, including nitrogen-ice plains informally known as Sputnik Planitia, rugged mountains made of water ice, and cratered regions. The simulated flight path takes the viewer across these varied landscapes, offering a stunning perspective of Pluto's complex geology. The coloration is exaggerated to emphasize the different surface compositions.
Ed Smylie, a NASA engineer crucial to the Apollo 13 rescue, died at 95. He designed the makeshift carbon dioxide scrubber that saved the astronauts from asphyxiation after an oxygen tank exploded, famously using duct tape and other readily available materials based on instructions radioed from Mission Control. His quick thinking and ingenuity under immense pressure were essential to the mission's survival and became a legendary example of improvisation in the face of a life-or-death crisis.
HN commenters express admiration for Ed Smylie's ingenuity and quick thinking in devising the carbon dioxide scrubber adapter that saved the Apollo 13 astronauts. Several highlight the contrast between this crucial, life-saving hack and the advanced technology surrounding the mission, emphasizing the importance of practical skills and improvisation. Some commenters share anecdotes about meeting Smylie or hearing him speak, describing him as humble and down-to-earth. Others discuss the broader significance of the Apollo 13 mission and the collaborative effort that brought the crew home safely. A few users also correct minor details in the original article or provide additional context about the mission and the lunar module's life support systems.
The post details how the author used publicly available data from NASA's SMAP (Soil Moisture Active Passive) satellite to pinpoint the location of illegal radio frequency interference in the protected L-band, specifically around 1.4 GHz. This frequency is crucial for scientific applications like SMAP's soil moisture and ocean salinity measurements. The interference, likely from a poorly configured or malfunctioning transmitter, was strong enough to significantly disrupt SMAP's data collection. By analyzing the satellite's radiometer data and employing basic trigonometry, the author was able to triangulate the source of the interference to a relatively small area, demonstrating a practical and accessible method for identifying such disruptions and protecting critical scientific bands.
Hacker News users generally agreed with the article's premise about the increasing difficulty of radio astronomy due to interference from terrestrial sources. Several commenters highlighted the importance of protecting radio astronomy for scientific discovery, with some suggesting stricter regulations or international cooperation to manage spectrum allocation. Others discussed technical details, such as the challenges of filtering interference and the limitations of existing satellite technology. A few pointed out the broader issue of balancing scientific needs with commercial interests in a world with increasingly congested electromagnetic spectrum. One commenter suggested the possibility of intentional interference, highlighting the vulnerability of these scientific instruments. There was also discussion around the specific case of SMAP and the difficulty in pinpointing the source of interference due to its wide observation swathe.
This paper explores the use of evolutionary algorithms (specifically, a co-evolutionary particle swarm optimization algorithm) to automate the design of antennas. It demonstrates the algorithm's effectiveness by designing several antennas, including a patch antenna, a Yagi-Uda antenna, and a wire antenna, for various target performance characteristics. The algorithm optimizes antenna geometry (like element lengths and spacing) directly from electromagnetic simulations, eliminating the need for extensive manual tuning. Results show that the evolved antennas achieve competitive performance compared to traditionally designed antennas, showcasing the potential of evolutionary computation for complex antenna design problems and potentially enabling novel antenna configurations not easily conceived through conventional methods.
Hacker News users discussed the surprising effectiveness of evolutionary algorithms (EAs) for antenna design, particularly in finding novel, non-intuitive designs that outperform human-engineered ones. Several commenters pointed out the paper's age (2006) and questioned if the field has advanced significantly since then, wondering about the current state-of-the-art. Some highlighted the potential of EAs in other domains and the inherent challenge of understanding why these algorithms arrive at their solutions. The lack of readily available commercial EA software was also mentioned, with speculation that the complexity of setting up and running these algorithms might be a barrier to wider adoption. Finally, the discussion touched upon the "black box" nature of EAs and the difficulty in extracting design principles from the evolved solutions.
Voyager 1, despite being billions of miles away, experienced an anomaly where its attitude articulation and control system (AACS) sent garbled telemetry data, even though the probe remained operational. Engineers diagnosed the issue as the AACS inadvertently sending data through a defunct onboard computer, which corrupted the information. The team successfully commanded Voyager 1 to switch back to the correct computer for telemetry, resolving the anomaly. Though the root cause of why the AACS routed data through the wrong computer remains unknown, Voyager 1 is now functioning as expected, sending back clear telemetry.
The Hacker News comments express admiration for the Voyager team's ingenuity and perseverance in diagnosing and fixing the anomaly from such a vast distance. Several commenters highlight the impressive feat of debugging a 50-year-old system with limited telemetry and communication. Some discuss the technical aspects of the problem and solution, including the use of the AACS's articulation test mode and the likely cause being a faulty component sending erroneous commands. Others reflect on the historical significance of Voyager and the dedication of the engineers involved, both past and present. A few commenters mention the emotional impact of the mission's continued success and the awe-inspiring nature of exploring interstellar space.
NASA's Curiosity rover has discovered extensive carbonate deposits within Mars' Gale Crater, significantly larger than any previously found. This discovery, based on data from the rover's ChemCam instrument, suggests prolonged interaction between liquid water and basaltic rocks in a neutral-to-alkaline pH environment, potentially creating conditions favorable to ancient life. The carbonates, found in a "transition zone" between a clay-rich layer and a sulfate-rich layer, offer clues about Mars' changing climate and past habitability. This finding reinforces the notion that early Mars may have been more Earth-like than previously thought.
HN commenters discuss possible explanations for the large carbonate deposits found by Curiosity, including biological origins, though largely favoring abiotic processes. Several highlight the difficulty of definitively proving biological influence, especially given the challenges of remote sample analysis. Some suggest volcanic activity or serpentinization as alternative explanations. The Martian environment's history of liquid water is noted, with some speculating about past habitability. Others question the significance of the finding, pointing out carbonates are already known to exist on Mars. A few commenters express excitement about the potential implications for understanding Mars's past and the search for life beyond Earth.
The "Whoosh Rocket" is a simple experiment demonstrating Newton's Third Law of Motion (for every action, there's an equal and opposite reaction). A plastic bottle, partially filled with water and pressurized with air, launches upwards when the air is released. The compressed air exerts force equally in all directions inside the bottle. When the stopper is removed, the air rushes out the opening, creating thrust. This downward force of the escaping air creates an equal and opposite upward force on the bottle, propelling it skyward. The amount of water affects the rocket's performance – too little and there isn't enough mass to be propelled efficiently; too much and the extra weight hinders its flight.
The Hacker News comments on the NASA "Whoosh Rocket" article largely focus on the surprising amount of thrust generated by this simple demonstration. Several commenters express fascination with the physics involved and the counterintuitive nature of the thrust being independent of the surrounding air pressure. Some discuss the educational value of the experiment, highlighting its simplicity and effectiveness in illustrating fundamental principles of rocket propulsion. One commenter provides further context by linking to a video demonstrating the experiment in a vacuum chamber, reinforcing the concept of thrust being generated solely by the expelled propellant. Another points out the historical significance of the experiment, linking it to a similar demonstration performed by Robert Goddard, considered the father of modern rocketry. There's a brief discussion comparing this type of rocket to other propulsion systems, and one user asks a clarifying question about the relevance of nozzle shape.
NASA's Athena lander successfully touched down near the lunar south pole, within a permanently shadowed crater. While the landing was considered a triumph, the extreme cold of -280°F (-173°C) presents a significant challenge for the mission's scientific objectives, which include searching for water ice and characterizing the lunar environment. The frigid temperatures will limit the lander's operational lifespan and complicate data collection. Despite this, the mission team is optimistic about Athena's ability to return valuable data from this unexplored region of the Moon.
Hacker News users discuss the surprisingly low temperature of -280°F (-173°C) recorded by Astrobotic's Peregrine lander, named Athena, after landing in a permanently shadowed crater. Several commenters point out that this temperature, while cold, isn't unexpected for a permanently shadowed region and is well above absolute zero. They discuss the possibility of finding water ice at such locations, with some speculating about its potential uses for future lunar missions. The discrepancy between Celsius and Fahrenheit scales is also mentioned, highlighting the importance of context when discussing extreme temperatures. Some users express skepticism about the viability of commercial lunar missions given Astrobotic's struggles.
NASA's SPHEREx mission, a near-infrared space telescope, is set to launch no earlier than June 2025. Its two-year mission will map the entire sky four times, creating a massive 3D map of hundreds of millions of galaxies and more than 100 million stars in the Milky Way. This data will help scientists study the early universe's expansion, the origin of water and other life-sustaining molecules, and the formation of galaxies.
Hacker News users generally expressed excitement about the SPHERX mission and its potential to expand our understanding of the universe. Several commenters discussed the implications of mapping such a vast number of galaxies for studying dark energy and cosmic inflation. Some questioned the $98M budget, wondering how it could be so low compared to other space telescopes. A few users highlighted the importance of near-infrared spectroscopy in SPHERX's mission, while others discussed the trade-offs between cost and scientific capabilities compared to larger telescopes. Technical details, like the use of a two-mirror, three-element unobscured anastigmat telescope, were also mentioned. There's a thread discussing the lack of detail in the NBC article and the need for more comprehensive reporting on scientific endeavors. Finally, some commenters expressed hope for discovering signs of extraterrestrial life or other unexpected phenomena.
To extend the Voyager probes' lifespans, NASA has turned off the Cosmic Ray Subsystem (CRS) instrument on Voyager 2. While the CRS has been crucial in studying the heliosphere and interstellar space, this power-saving measure is necessary to keep both Voyager 1 and 2 operating. Further power reductions are planned in the coming years as the probes' radioactive power sources continue to decay, with the goal of maintaining communication with Earth for as long as possible. Voyager 1's CRS was deactivated in 2022.
HN commenters express a mix of awe and sadness at the continued power-down of the Voyager probes. Several reflect on the incredible longevity and distance of the mission, marveling at the ingenuity of the engineers who designed them. Some commenters discuss the technical aspects of the power reduction, including the use of radioisotope thermoelectric generators (RTGs) and the diminishing power output over time. Others lament the eventual loss of contact, viewing it as a symbolic end of an era. A few suggest potential solutions, albeit highly speculative ones, like laser-based power beaming to extend the probes' lifespans. The overall sentiment is one of respect for the Voyager mission and its contributions to scientific understanding.
NASA has successfully demonstrated the ability to receive GPS signals at the Moon, a first for navigating beyond Earth’s orbit. The Navigation Doppler Lidar for Space (NDLS) experiment aboard the Lunar Reconnaissance Orbiter (LRO) locked onto GPS signals and determined LRO’s position, paving the way for more reliable and autonomous navigation for future lunar missions. This achievement reduces reliance on Earth-based tracking and allows spacecraft to more accurately pinpoint their location, enabling more efficient and flexible operations in lunar orbit and beyond.
Several commenters on Hacker News expressed skepticism about the value of this achievement, questioning the practical applications and cost-effectiveness of using GPS around the Moon. Some suggested alternative navigation methods, such as star trackers or inertial systems, might be more suitable. Others pointed out the limitations of GPS accuracy at such distances, especially given the moon's unique gravitational environment. A few commenters highlighted the potential benefits, including simplified navigation for lunar missions and improved understanding of GPS signal behavior in extreme environments. Some debated the reasons behind NASA's pursuit of this technology, speculating about potential future applications like lunar infrastructure development or deep space navigation. There was also discussion about the technical challenges involved in acquiring and processing weak GPS signals at such a distance.
NASA's video covers the planned lunar landing of Firefly Aerospace's Blue Ghost Mission 1 lander. This mission marks Firefly's inaugural lunar landing and will deliver several NASA payloads to the Moon's surface to gather crucial scientific data as part of the agency's Commercial Lunar Payload Services (CLPS) initiative. The broadcast details the mission's objectives, including deploying payloads that will study the lunar environment and test technologies for future missions. It also highlights Firefly's role in expanding commercial access to the Moon.
HN commenters express excitement about Firefly's upcoming moon landing, viewing it as a significant step for private space exploration and a positive development for the US space industry. Some discuss the technical challenges, like the complexities of lunar landing and the need for a successful landing to validate Firefly's technology. Others highlight the mission's scientific payloads and potential future implications, including resource utilization and lunar infrastructure development. A few commenters also mention the importance of competition in the space sector and the role of smaller companies like Firefly in driving innovation. There's some discussion of the mission's cost-effectiveness compared to larger government-led programs.
Powerful new magnets built for NASA's next-generation electric propulsion system have passed initial testing and are ready for space-like conditions. These magnets, made of a high-temperature superconducting material, are crucial to the Advanced Electric Propulsion System (AEPS) which aims to significantly shorten travel times for future deep-space missions like Mars trips. The magnets enable the Hall thruster to achieve higher power and efficiency compared to current technology, pushing spacecraft faster while using less propellant. They will now undergo rigorous testing in a vacuum chamber that simulates the harsh environment of space.
Hacker News commenters discuss the potential of the new magnet technology for electric propulsion. Some express excitement about the increased efficiency and power density offered by these superconducting magnets, envisioning applications beyond just the VASIMR engine, like fusion power. Others are more cautious, pointing to the challenges of maintaining cryogenic temperatures in space and the need for radiation shielding. Several commenters delve into technical details, comparing different thruster types (Hall effect, ion, etc.) and the specific advantages of high-temperature superconductors. There's also a thread discussing the complexities of testing in space and the long road to practical implementation for technologies like VASIMR. Overall, while acknowledging the hurdles, commenters seem optimistic about the progress and potential impact of this magnetic technology on space travel.
The James Webb Space Telescope has revealed intricate networks of dust filaments within the nearby galaxy IC 5146, offering unprecedented detail of the interstellar medium. This "cosmic web" of dust, illuminated by newborn stars, traces the distribution of material between stars and provides insights into how stars form and influence their surrounding environments. Webb's infrared capabilities allowed it to penetrate the dust clouds, revealing previously unseen structures and providing valuable data for understanding the lifecycle of interstellar dust and the processes of star formation.
Hacker News users discuss the implications of the Webb telescope's discovery of complex organic molecules in a young, distant galaxy. Some express awe at the technology and the scientific advancements it enables, while others delve into the specific findings, pondering the presence of polycyclic aromatic hydrocarbons (PAHs) and their significance for the possibility of life. Several commenters highlight the relatively early stage of these discoveries and anticipate future, even more detailed observations. A degree of skepticism is also present, with users questioning the certainty of attributing these complex molecules specifically to the early galaxy, as opposed to potential foreground contamination. The potential for JWST to revolutionize our understanding of the universe is a recurring theme.
NASA's Parker Solar Probe is about to make its closest approach to the Sun yet, diving deeper into the solar corona than ever before. This daring maneuver, occurring in late December 2024, will bring the spacecraft within 7.3 million kilometers of the solar surface, subjecting it to extreme temperatures and radiation. Scientists anticipate this close flyby will provide invaluable data about the Sun's magnetic field, solar wind, and coronal heating, potentially unraveling longstanding mysteries about our star's behavior.
Hacker News commenters discussed the practicality of calling the Solar Probe Plus mission "flying into the Sun" given its closest approach is still millions of miles away. Some pointed out that this distance, while seemingly large, is within the Sun's corona and a significant achievement. Others highlighted the incredible engineering required to withstand the intense heat and radiation, with some expressing awe at the mission's scientific goals of understanding solar wind and coronal heating. A few commenters corrected the title's claim of being the "first time," referencing previous missions that have gotten closer, albeit briefly, during a solar grazing maneuver. The overall sentiment was one of impressed appreciation for the mission's ambition and complexity.
Amateur radio operators successfully detected the faint signal of Voyager 1, the most distant human-made object, using the Dwingeloo radio telescope in the Netherlands. Leveraging Voyager 1's predictable signal pattern and the telescope's sensitivity, they confirmed the spacecraft's carrier signal, demonstrating the impressive capabilities of both the aging probe and the terrestrial equipment. This marks a significant achievement for the amateur radio community and highlights the enduring legacy of the Voyager mission.
Hacker News commenters express excitement and awe at the ingenuity involved in receiving Voyager 1's faint signal with the Dwingeloo telescope. Several discuss the technical aspects, highlighting the remarkably low power of Voyager's transmitter (now around 13.8W) and the sophisticated signal processing required for detection. Some marvel at the vast distance and the implications for interstellar communication, while others share personal anecdotes about their involvement with the Voyager missions or similar projects. A few commenters clarify the role of ham radio operators, emphasizing their contribution to signal processing rather than direct reception of the raw signal, which was achieved by the professional astronomers. There's also discussion of the signal's characteristics and the use of the Deep Space Network for primary communication with Voyager.
Voyager 1, currently over 15 billion miles from Earth, successfully transmitted data using a backup thruster control system not activated since 1981. NASA engineers recently rediscovered the system's functionality and tested it, confirming Voyager 1 can still send scientific data back to Earth via this alternative route. This extends the spacecraft's operational lifespan, though using the backup system requires slightly higher power consumption. While the primary thruster control system remains functional for now, this rediscovery provides a valuable backup communication method for the aging probe.
Hacker News commenters generally expressed awe and excitement at Voyager 1's continued operation and the ingenuity of the engineers who designed and maintain it. Several commenters highlighted the remarkable longevity and durability of the spacecraft, given its age and the harsh environment of interstellar space. Some discussed the technical details of the trajectory correction maneuver and the specific hardware involved, including the attitude control thrusters and the now-resurrected TCM thruster. A few questioned the phrasing of "breaking its silence," pointing out that Voyager 1 continues to send scientific data. Others reflected on the historical significance of the Voyager missions and the small, but important, course correction that ensures continued communication with Earth for a few more years.
Summary of Comments ( 10 )
https://news.ycombinator.com/item?id=44022233
HN users discuss various technical aspects of the New Horizons flyby and the resulting imagery. Some express awe at the feat of navigating to Pluto and the detail captured. Several commenters analyze the image processing techniques, noting the use of range maps and digital elevation models to create the flyover effect. They also discuss the challenges of accurately representing the subtle color variations and the difficulty in interpreting geological features due to the unfamiliar terrain. Others compare the flyover visualization to older, less detailed representations of Pluto, highlighting the advancement in our understanding. There's also some discussion of the mission's power source, the use of plutonium, and its longevity.
The Hacker News post titled "Pluto Flyover from New Horizons" contains several comments discussing various aspects of the flyby and its implications.
Several commenters express awe and wonder at the achievement and the imagery. One user highlights the incredible feat of sending a probe billions of miles to capture such detailed images, emphasizing the precision and planning involved. Others echo this sentiment, marveling at the vastness of space and humanity's ability to explore it.
A thread emerges discussing the classification of Pluto as a dwarf planet. Some commenters lament the reclassification, expressing nostalgia for its former status as a planet. Others defend the decision, explaining the criteria used for planetary classification and pointing out that Pluto doesn't meet all the requirements. This leads to a debate about the arbitrary nature of classifications and the evolving understanding of celestial bodies.
Some comments delve into the technical aspects of the mission, including the challenges of transmitting data from such a vast distance and the innovative techniques used to capture the images. One user questions why the video appears sped up, prompting another to explain that it's a time-lapse composed of numerous still images taken over time, not a real-time recording.
Several commenters express excitement about future space exploration, hoping for similar missions to other celestial bodies in the Kuiper Belt and beyond. They discuss the potential for discovering new insights into the formation of the solar system and the possibility of finding evidence of life.
Some users share personal anecdotes about their interest in space and how events like the New Horizons flyby have inspired them. One user reminisces about watching the original moon landing, connecting it to the current achievement as a continuation of humanity's drive to explore.
A few comments mention the processing of the images, discussing color enhancement and other techniques used to create the final product. One user points out the presence of a "processed image" watermark, prompting a discussion about image authenticity and the importance of distinguishing between raw data and enhanced visuals.
Overall, the comments reflect a mix of awe, scientific curiosity, and nostalgia, highlighting the significance of the New Horizons mission and its impact on our understanding of the solar system.