Workflow
哈勃空间望远镜
icon
Search documents
“哈勃”观测到罕见“宇宙撞击”
Ke Ji Ri Bao· 2025-12-24 01:02
Core Findings - An international study led by Northwestern University utilized the Hubble Space Telescope to observe a rare "cosmic collision" in a nearby planetary system, revealing that dust clouds may masquerade as planets for years [1][2] - This discovery aids in understanding planetary formation mechanisms and the structural characteristics of asteroids, which is significant for planetary defense initiatives like the Double Asteroid Redirection Test (DART) [1] Research Process - Since 1993, scientists have been observing the star Beta Pictoris, located 25 light-years from Earth, which has a large and complex debris disk, making it an ideal research target [1] - In 2008, a bright point in the debris disk was mistakenly identified as a planet and named "Beta Pictoris b" [1] - In 2023, follow-up observations revealed that this bright point had disappeared, leading to the discovery of a new bright spot, "Beta Pictoris cs2," which showed a 30% increase in brightness [1] Findings on Dust Clouds - The disappearance of "Beta Pictoris b" supports the hypothesis that it was a transient dust cloud generated by a collision, while the new bright spot "Beta Pictoris cs2" further confirms that both are not planets but rather dust clouds formed from the collision of small rocky bodies similar to asteroids [2] - For several years, signals from such dust clouds may closely resemble those from planets, making it crucial to accurately distinguish between transient collision dust clouds and actual exoplanets with the advent of next-generation observational equipment like the Giant Magellan Telescope [2]
美航天局公布“星际访客”彗星最新图像
Xin Hua She· 2025-11-20 06:56
Core Points - NASA has released new images of the interstellar visitor comet 3I/ATLAS, which is expected to pass Earth around December 19, at a distance of approximately 270 million kilometers, about twice the distance from Earth to the Sun [1] - The comet was first discovered by the ATLAS survey telescope in Chile on July 1, and it is the third interstellar object observed in the solar system [1] - A total of 12 NASA instruments, including the Hubble Space Telescope and the James Webb Space Telescope, have captured images of the comet, with more observations expected as it continues its journey through the solar system [1] - The comet passed within 30 million kilometers of Mars this autumn, where three Mars rovers observed it, and other NASA spacecraft also tracked it [1] - Researchers believe that 3I/ATLAS originated from an external star system and has been drifting in interstellar space for millions to billions of years before entering the solar system [1] Naming Significance - The name of the comet contains its "identity code": "ATLAS" represents the discovery team, "I" indicates it is an interstellar object, and "3" signifies it is the third confirmed interstellar body [2]
跨135亿年历史的最大宇宙图谱发布
Qi Lu Wan Bao· 2025-06-07 04:04
Core Insights - The COSMOS-Web project has released the largest cosmic map and observational data to date, based on data collected by the James Webb Space Telescope (JWST), covering over 780,000 galaxies and spanning 13.5 billion years, which represents 98% of the universe's history [1][2] - The goal of the research team is to create an unprecedented ultra-deep wide-angle image of the universe, with the COSMOS-Web image being equivalent to a mural of approximately 4 meters in length and over 15 square meters in area, significantly larger than the Hubble Space Telescope's deep field image [1] - JWST has discovered a number of ancient galaxies far exceeding expectations, finding ten times more galaxies than previously predicted within the first 500 million years after the universe's birth, along with supermassive black holes that were undetectable during the Hubble era [2] Data and Accessibility - The released data includes not only ultra-deep space images but also a detailed galaxy catalog, which is made available to researchers worldwide [3]
“系外生命”是否存在?
Ren Min Ri Bao· 2025-06-03 09:18
Core Findings - An international team led by astronomer Nikku Madhusudhan from Cambridge University has published findings in the Astrophysical Journal Letters, indicating the discovery of the "strongest evidence" for potential life activity outside the solar system in the atmosphere of exoplanet K2-18b, located approximately 124 light-years away from Earth [1][2] - The atmosphere of K2-18b contains chemical signatures of dimethyl sulfide (DMS) and dimethyl disulfide (DMDS), which are associated with biological processes on Earth [1][2] - This research utilized the James Webb Space Telescope (JWST) to analyze the starlight passing through the planet's atmosphere, revealing the presence of these complex organic molecules, which are more intricate than methane [1][2] Exoplanet Characteristics - K2-18b is one of the most common types of exoplanets discovered, with a mass approximately 8.6 times that of Earth and a volume about 2.6 times larger, situated within the habitable zone [2] - Previous studies using the Hubble Space Telescope suggested that K2-18b's atmosphere was rich in water vapor, although later analyses indicated that the observed water vapor might actually be methane [2] - The recent study confirmed the presence of methane and carbon dioxide in K2-18b's atmosphere and proposed the existence of dimethyl sulfide for the first time, achieving a detection confidence level of 3.4, which is considered a significant threshold in astronomical observations [2] Scientific Debate - There is skepticism among some researchers regarding the findings, with concerns about potential noise interference in the observational data and the possibility that reported features could be statistical fluctuations [3] - Alternative models could explain the observed data, and some scientists suggest that K2-18b may resemble a gaseous planet like Neptune, potentially lacking a solid surface [3] - The origin of dimethyl sulfide is also debated, with some experts proposing that it could arise from non-biological processes or even from interstellar medium [3] Future Exploration - The search for extraterrestrial life continues to be a significant focus, with various countries developing plans for exoplanet exploration, including China's Tianling Plan and the U.S. Habitable Worlds Observatory project [4] - Advancements in astronomical telescopes, atmospheric modeling, and astrobiology are expected to enhance the understanding of potential life signals in the universe [4]