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By European Space Agency
On 1 December 2024, BepiColombo flew past Mercury for the fifth time. During this flyby, BepiColombo became the first spacecraft ever to observe Mercury in mid-infrared light. The new images reveal variations in temperature and composition across the planet's cratered surface.
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By USH
A rare and intriguing phenomenon has been observed in China. On the night of October 27th, Chinese astrophotographer Shengyu Li set up his camera to capture star trails over Mount Xiannairi in Sichuan Province. To his surprise, he recorded mysterious blue flashes accompanying an avalanche.
The exact cause of these "blue lights" remains unclear, sparking various theories. Some speculate they could stem from geomagnetic activity, interactions of cosmic rays in the upper atmosphere, or rare atmospheric phenomena like blue jets or elves. However, Li offers another explanation: the flashes might result from triboluminescence—light produced by friction during ice fragmentation.
Triboluminescence occurs when certain materials emit light as they are fractured, scratched, or rubbed. This phenomenon happens due to the breaking of chemical bonds or the sudden separation of surfaces, which generates electrical charges. These charges can ionize the surrounding air or excite the material itself, creating visible light.
The hypothesis suggests that this event could be an example of triboluminescence. However, it also raises the intriguing possibility of a connection to UFO phenomena, such as orbs or other unexplained lights that have been observed around the world over the years.
Hypothesis: The sighting depicts what appears to be a blue light descending onto a snowbank, following the avalanche as it moves downward, and then vanishing before seemingly ascending again.
Did the avalanche trigger the blue light, or did the blue light crash into the snow, causing the avalanche?
Whether this phenomenon is a rare case of triboluminescence, potentially the first instance of it being captured on camera or something linked to unexplained UFO activity, the recording of this light remains a unique and fascinating occurrence. View the full article
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By USH
The Colares UFO incidents refer to a series of unusual sightings and encounters that took place in 1977 on the Brazilian island of Colares. During this period, numerous residents from the Amazon River community of Colares reported being attacked by UFOs.
These mysterious objects allegedly descended from the sky, and in some cases, emerged from the water, emitting intense beams of light. The beams caused physical harm, including burn marks, puncture wounds, fatigue, and memory loss, affecting as many as 2,000 people.
In response to the alarming situation, the Brazilian Air Force initiated a thorough investigation. Years later, their findings were made public, revealing details of this bizarre chapter in UFO history.
Weaponized hosts Jeremy and George speak with Thiago Ticchetti, Brazil's leading UFO investigator and author, to discuss the Colares case and the once-classified military files.
According to Thiago, the Brazilian military captured remarkably clear film footage and photographs of the UFOs. However, he claims that this evidence was sent to the U.S. and has never been released to the public.
In this episode, they also explores various conspiracy theories and recent debunking efforts surrounding the topic of unidentified aerial phenomena (UAP).
The discussion on the Colares UFO incidents begins at the 37-minute mark in the video.
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By NASA
2 min read
Hubble Reaches a Lonely Light in the Dark
NASA, ESA, C. Gallart (Instituto de Astrofisica de Canarias), A. del Pino Molina (Centro de Estudios de Fisica del Cosmos de Aragon), and R. van der Marel (Space Telescope Science Institute); Image Processing: Gladys Kober (NASA/Catholic University of America) A splatter of stars glows faintly at almost 3 million light-years away in this new image from NASA’s Hubble Space Telescope. Known as the Tucana Dwarf for lying in the constellation Tucana, this dwarf galaxy contains a loose bundle of aging stars at the far edge of the Local Group, an aggregation of galaxies including our Milky Way, bound together by gravity. The Tucana Dwarf was discovered in 1990 by R.J. Lavery, the same year Hubble launched.
What makes the Tucana Dwarf distinct from other dwarf galaxies comes in two parts: its classification, and its isolation. As a dwarf spheroidal galaxy, it is much smaller and less luminous than most other dwarf galaxies. Dust is sparse and the stellar population skews towards the older range, giving them a dimmer look. Additionally, the Tucana Dwarf lies about 3.6 million light-years from the Local Group’s center of mass, far from the Milky Way and other galaxies. It is only one of two dwarf spheroidal galaxies in the Local Group to be this remote, making astronomers theorize that a close encounter with a larger galactic neighbor called Andromeda slingshotted it into the distance about 11 billion years ago.
Having such pristine properties enables scientists to use the Tucana Dwarf as a cosmic fossil. Dwarf galaxies could be the early ingredients for larger galaxies, and with older stars residing in such an isolated environment, analyzing them can help trace galaxy formation back to the dawn of time. For that reason, Hubble reached far across the Local Group using the capabilities of the Advanced Camera for Surveys and Wide Field and Planetary Camera 2 to meet this distant, lonely galaxy. Examining its structure, composition, and star formation history sheds light on the epoch of reionization, when the first stars and galaxies arose from the dark billions of years ago.
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Last Updated Aug 23, 2024 Editor Michelle Belleville Location NASA Goddard Space Flight Center Related Terms
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Since its 1990 launch, the Hubble Space Telescope has changed our fundamental understanding of the universe.
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By NASA
5 min read
NASA’s DART Mission Sheds New Light on Target Binary Asteroid System
The various geological features observed on Didymos helped researchers tell the story of Didymos’ origins. The asteroid’s triangular ridge (first panel from left), and the so-called smooth region, and its likely older, rougher “highland” region (second panel from left) can be explained through a combination of slope processes controlled by elevation (third panel from left). The fourth panel shows the effects of spin-up disruption that Didymos likely underwent to form Dimorphos. Credit: Johns Hopkins APL/Olivier Barnouin In studying data collected from NASA’s DART (Double Asteroid Redirection Test) mission, which in 2022 sent a spacecraft to intentionally collide with the asteroid moonlet Dimorphos, the mission’s science team has discovered new information on the origins of the target binary asteroid system and why the DART spacecraft was so effective in shifting Dimorphos’ orbit.
In five recently published papers in Nature Communications, the team explored the geology of the binary asteroid system, comprising moonlet Dimorphos and parent asteroid Didymos, to characterize its origin and evolution and constrain its physical characteristics.
“These findings give us new insights into the ways that asteroids can change over time,” said Thomas Statler, lead scientist for Solar System Small Bodies at NASA Headquarters in Washington. “This is important not just for understanding the near-Earth objects that are the focus of planetary defense, but also for our ability to read the history of our Solar System from these remnants of planet formation. This is just part of the wealth of new knowledge we’ve gained from DART.”
Olivier Barnouin and Ronald-Louis Ballouz of Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, led a paper that analyzed the geology of both asteroids and drew conclusions about their surface materials and interior properties. From images captured by DART and its accompanying LICIACube cubesat – contributed by the Italian Space Agency (ASI), the team observed the smaller asteroid Dimorphos’ topography, which featured boulders of varying sizes. In comparison, the larger asteroid Didymos was smoother at lower elevations, though rocky at higher elevations, with more craters than Dimorphos. The authors inferred that Dimorphos likely spun off from Didymos in a large mass shedding event.
There are natural processes that can accelerate the spins of small asteroids, and there is growing evidence that these processes may be responsible for re-shaping these bodies or even forcing material to be spun off their surfaces.
Analysis suggested that both Didymos and Dimorphos have weak surface characteristics, which led the team to posit that Didymos has a surface age 40–130 times older than Dimorphos, with the former estimated to be 12.5 million years and the latter less than 300,000 years old. The low surface strength of Dimorphos likely contributed to DART’s significant impact on its orbit.
“The images and data that DART collected at the Didymos system provided a unique opportunity for a close-up geological look of a near-Earth asteroid binary system,” said Barnouin. “From these images alone, we were able to infer a great deal of information on geophysical properties of both Didymos and Dimorphos and expand our understanding on the formation of these two asteroids. We also better understand why DART was so effective in moving Dimorphos.”
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Based on the internal and surface properties described in Barnouin et al. (2024), this video demonstrates how the spin-up of asteroid Didymos could have led to the growth of its equatorial ridge and the formation of the smaller asteroid Dimorphos, seen orbiting the former near the end of the clip. Particles are colored according to their speeds, with the scale shown at the top, along with the continually changing spin period of Didymos. Credit: University of Michigan/Yun Zhang and Johns Hopkins APL/Olivier Barnouin Maurizio Pajola, of the National Institute for Astrophysics (INAF) in Rome, and co-authors led a paper comparing the shapes and sizes of the various boulders and their distribution patterns on the two asteroids’ surfaces. They determined the physical characteristics of Dimorphos indicate it formed in stages, likely of material inherited from its parent asteroid Didymos. That conclusion reinforces the prevailing theory that some binary asteroid systems arise from shed remnants of a larger primary asteroid accumulating into a new asteroid moonlet.
Alice Lucchetti, also of INAF, and colleagues found that thermal fatigue — the gradual weakening and cracking of a material caused by heat — could rapidly break up boulders on the surface of Dimorphos, generating surface lines and altering the physical characteristics of this type of asteroid more quickly than previously thought. The DART mission was likely the first observation of such a phenomenon on this type of asteroid.
Supervised by researcher Naomi Murdoch of ISAE-SUPAERO in Toulouse, France, and colleagues, a paper led by students Jeanne Bigot and Pauline Lombardo determined Didymos’ bearing capacity — the surface’s ability to support applied loads — to be at least 1,000 times lower than that of dry sand on Earth or lunar soil. This is considered an important parameter for understanding and predicting the response of a surface, including for the purposes of displacing an asteroid.
Colas Robin, also of ISAE-SUPAERO, and co-authors analyzed the surface boulders on Dimorphos, comparing them with those on other rubble pile asteroids, including Itokawa, Ryugu and Bennu. The researchers found the boulders shared similar characteristics, suggesting all these types of asteroids formed and evolved in a similar fashion. The team also noted that the elongated nature of the boulders around the DART impact site implies that they were likely formed through impact processing.
These latest findings form a more robust overview of the origins of the Didymos system and add to the understanding of how such planetary bodies were formed. As ESA’s (European Space Agency) Hera mission prepares to revisit DART’s collision site in 2026 to further analyze the aftermath of the first-ever planetary defense test, this research provides a series of tests for what Hera will find and contributes to current and future exploration missions while bolstering planetary defense capabilities.
Johns Hopkins APL managed the DART mission for NASA’s Planetary Defense Coordination Office as a project of the agency’s Planetary Missions Program Office. NASA provided support for the mission from several centers, including the Jet Propulsion Laboratory in Southern California, Goddard Space Flight Center in Greenbelt, Maryland, Johnson Space Center in Houston, Glenn Research Center in Cleveland, and Langley Research Center in Hampton, Virginia.
For more information about the DART mission:
https://science.nasa.gov/planetary-defense-dart
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Last Updated Jul 30, 2024 Related Terms
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