Tag Archives: astronomical

Hubble Space Telescope Returns to the Famous Crab Nebula: A New Look at an Iconic Astronomical Marvel

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By analyzing new observations from Hubble alongside images captured in 1999, astronomers have successfully tracked the continuing expansion of one of the sky’s most studied supernova remnants, the Crab Nebula. This expansion is fueled by a rapidly spinning pulsar at its core.

This captivating image of the Crab Nebula was taken by the NASA/ESA Hubble Space Telescope in 2024. Image credit: NASA/ESA/STScI/William Blair, JHU/Joseph DePasquale, STScI.

In 1054, astounded Chinese astronomers witnessed a remarkably bright nova, the second brightest object in the night sky after the moon, visible even during the daytime for a remarkable 23 days. Observations of this supernova were also documented by Japanese, Arabian, and Native American astronomers.

Today, the luminous Crab Nebula, also known as Messier 1, M1, NGC 1952, or Taurus A, occupies the position of that brilliant star, situated approximately 6,500 light-years away in the constellation Taurus.

This nebula’s brightness makes it visible even through amateur telescopes, making it a popular object for stargazers.

Initially identified in 1731 by the English physicist and astronomer John Beavis, the Crab Nebula was later rediscovered in 1758 by French astronomer Charles Messier.

The name “Crab Nebula” derives from its resemblance in an 1844 painting by Irish astronomer Lord Rose.

At its center lies the remnant core of the original star, known as the Crab Pulsar (PSR B0531+21).

“We often perceive the sky as a static body,” remarked Dr. William Blair, an astronomer at Johns Hopkins University. “However, the enduring journey of the NASA/ESA Hubble Space Telescope has shown us that the Crab Nebula continues to evolve and expand from the explosion that occurred nearly 1,000 years ago.”

In the latest images, Hubble revealed the nebula’s intricate filament structure, demonstrating substantial outward movement over a 25-year period at an astonishing rate of 5.6 million kilometers per hour (3.4 million miles per hour).

“Hubble possesses the unique longevity and resolution necessary to capture these intricate changes,” the astronomers noted.

To facilitate comparisons with new images, Hubble’s 1999 image of the Crab Nebula has undergone reprocessing.

“The color variations observed in both Hubble images signal changes in the gas’s local temperature, density, and chemical composition.”

“Even after extensive work with Hubble, I’m continually amazed by the detailed structure and improved resolution revealed by Hubble’s Wide Field Camera 3 (WFC3) compared to 25 years ago,” Dr. Blair commented.

“WFC3 was installed in 2009, marking the last time Hubble’s instrument was upgraded by astronauts.”

“The filaments at the edges of the nebula seem to be moving more rapidly than those at the center and appear to be expanding outward instead of stretching over time.”

This phenomenon is attributed to the pulsar’s nature as a pulsar wind nebula, driven by synchrotron radiation generated from interactions between the pulsar’s magnetic field and the surrounding nebula material.

In contrast, other notable supernova remnants typically expand in a manner influenced by shock waves from the initial explosion, which erode the outer shell of gas ejected by the dying star.

The new high-resolution observations from Hubble also offer deeper insights into the Crab Nebula’s three-dimensional structure, challenging to assess from two-dimensional images.

In an intriguing observation, shadows of some filaments are reflected in the haze of synchrotron radiation within the nebula.

Interestingly, some bright filaments in the latest Hubble images do not display shadows, suggesting they are located behind the nebula.

“The true significance of Hubble’s observations of the Crab Nebula is yet to unfold,” the researchers asserted.

“Data from Hubble can be integrated with recent findings from other telescopes observing the Crab Nebula across varying wavelengths of light.”

“NASA/ESA/CSA’s James Webb Space Telescope is set to release infrared light observations of the Crab Nebula in 2024.”

Comparing Hubble’s images with modern multiwavelength observations will provide scientists with a comprehensive understanding of the ongoing aftermath of supernovae, continuing to intrigue astronomers long after new stars first appeared in the sky.

Find more findings published in January 2026. Astrophysical Journal.

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William P. Blair et al. 2026. Revisiting the Crab Nebula using HST/WFC3. APJ 997, 81; doi: 10.3847/1538-4357/ae2adc

Source: www.sci.news

Supergiant Star Transitions to Hotter Phase: A Rare Astronomical Discovery

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In-depth observations of WOH G64, previously regarded as the most extreme red supergiant star in our galaxy, have uncovered significant changes, suggesting it may have shed parts of its outer layers while transitioning into a hotter, rarer stellar phase.

Artist’s reconstruction of the red supergiant star WOH G64. Image credit: ESO/L. Calçada.

Red supergiant stars, exceeding eight times the mass of the Sun, boast relatively short lifespans of merely 1 to 10 million years before culminating in a spectacular supernova explosion.

Despite their brightness, the evolutionary trajectories and ultimate fates of the universe’s most luminous red supergiants remain unclear.

Discovered in the 1980s, WOH G64 has been recognized as one of the brightest, largest, and coolest red supergiants within the Large Magellanic Cloud, a dwarf galaxy located approximately 160,000 light-years from Earth.

To explore the evolution of WOH G64, Dr. Gonzalo Muñoz Sánchez from the National Astronomical Observatory of Athens and his team analyzed over 30 years of brightness data, commencing in 1992, using both recent and archived electromagnetic spectra.

The research indicated that the star experienced rapid fluctuations: it dimmed in 2011, then rebounded, transforming into a yellower hue and increasing in temperature by over 1,000 degrees Celsius between 2013 and 2014.

In 2025, WOH G64 experienced a significant dimming, accompanied by alterations in its atmospheric chemistry.

This image, captured by ESO’s Very Large Telescope Interferometer’s GRAVITY instrument, showcases the red supergiant star WOH G64. Image credit: ESO/Ohnaka et al., doi: 10.1051/0004-6361/202451820.

Astronomers have proposed two possible explanations for these developments.

“First, WOH G64 could be part of a binary system where a red supergiant star transformed into a yellow supergiant due to interactions that expelled part of its atmosphere,” the researchers noted.

“Alternatively, the yellow supergiant may have experienced an eruption of red material lasting several decades, culminating in 2014.”

“This discovery raises intriguing questions about the nature of extreme red supergiants like WOH G64 and whether they are predominantly interacting binaries, which might prevent single stars from reaching such extreme conditions,” the researchers concluded.

The future interactions of WOH G64 will ultimately determine whether it explodes as a supernova, collapses into a black hole, or merges with a companion star.

For further details, refer to the study published in the journal Nature Astronomy.

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G. Munoz-Sanchez et al. A dramatic transformation from the very red supergiant WOH G64 to a yellow supergiant. Nat Astron, published online on February 23, 2026. doi: 10.1038/s41550-026-02789-7

Source: www.sci.news

Discovering a Triple System of Active Galactic Nuclei 1.2 Billion Light-Years Away: A Major Astronomical Breakthrough

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A rare triple-merger galaxy, known as J121/1219+1035, hosts three actively feeding radio-bright supermassive black holes, as revealed by a team of American astronomers.

Artist’s impression of J121/1219+1035, a rare trio of merging galaxies, featuring three radioactively bright supermassive black holes actively feeding, with jets illuminating the surrounding gas. Image credit: NSF/AUI/NRAO/P. Vosteen.

The J1218/1219+1035 system is located approximately 1.2 billion light-years from Earth.

This unique galaxy system contains three interacting galaxies, each harboring supermassive black holes at their centers that are actively accreting material and shining brightly in radio frequencies.

Dr. Emma Schwartzman, a research scientist at the US Naval Research Laboratory, states: “Triple active galaxies like J1218/1219+1035 are incredibly rare, and observing them during a merger allows us a front-row seat to the growth of supermassive galaxies and their black holes.”

“Our observations confirmed that all three black holes in J1218/1219+1035 are emitting bright radiation and actively firing jets. This supports the theory of active galactic nuclei (AGN) and provides insight into the life cycle of supermassive black holes.”

Schwartzman and colleagues utilized NSF’s Very Large Array (VLA) and Very Long Baseline Array (VLBA) to study J1218/1219+1035.

The findings confirmed that each galaxy hosts a compact synchrotron-emitting radio core, indicating that all three harbor AGNs powered by growing black holes.

This discovery makes J1218/1219+1035 the first confirmed triple radio AGN and only the third known triple AGN system in nearby space.

“The three galaxies within J1218/1219+1035, located about 22,000 to 97,000 light-years apart, are in the process of merging, resulting in a dynamically connected group with tidal signatures indicative of their interactions,” the astronomers noted.

“Such triple systems are crucial in the context of hierarchical galactic evolution, wherein large galaxies like the Milky Way grow through successive collisions and mergers with smaller galaxies, yet they are seldom observed.”

“By capturing three actively feeding black holes within the same merging group, our new observations create an excellent laboratory for testing how galactic encounters funnel gas into centers and stimulate black hole growth.”

J1218/1219+1035 was initially flagged as an anomalous system through mid-infrared data from NASA’s Wide-Field Infrared Surveyor (WISE), which suggested the presence of at least two obscured AGNs within the interacting galaxies.

Optical spectroscopy confirmed one AGN in a core while revealing complex signatures in another, although the nature of the third galaxy remained uncertain due to the possibility of emissions from star formation.

“Only through new ultra-sharp radio imaging with VLA at frequencies of 3, 10, and 15 GHz did we uncover compact radio cores aligned with all three optical galaxies, confirming that each hosts an AGN bright in radio emissions and likely fueling small-scale jets and outflows,” the researchers explained.

“The radio spectra of the three cores exhibited traits consistent with non-thermal synchrotron radiation from the AGNs, featuring two sources with typical steep spectra and a third with an even steeper spectrum potentially indicative of unresolved jet activity.”

Source: www.sci.news

Cameras Mimicking Human Vision Could Enhance Astronomical Discoveries

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Sirius Binary Star System Captured with a Neurotype Camera

Satyapreet Singh, Chetan Singh Thakur, Nirupam Roy, Indian Institute of Science, India

Neurotype cameras, designed to emulate human vision, offer significant benefits for astronomers by enabling the capture of both bright and dim celestial objects in a single frame. This allows for tracking swift-moving entities without the risk of motion blur.

Unlike conventional digital cameras that sample a grid of pixels multiple times per second, recording data for each pixel each time, neurotype cameras, or event cameras, function quite differently. Each pixel is activated only if there’s a change in brightness at that specific location. If the brightness remains constant, no new data is saved, resembling how the human eye processes visual information.

This innovative approach presents various benefits. By recording only changing pixels, less data is generated while maintaining a much higher frame rate. Furthermore, these cameras measure light on a logarithmic scale, enabling the detection of fainter objects next to brighter ones that may saturate conventional camera images.

To investigate the potential of this technology for astronomical applications, Chetan Singh Thakur and his team at the Indian Institute of Science in Bengaluru mounted a neurotype camera on a 1.3-meter telescope at the Aliyabatta Observatory in Uttarkhand, India.

They successfully captured meteoroids traveling between the Earth and the Moon and also obtained images of the Sirius binary system, which includes Sirius A, the brightest star in the night sky, and Sirius B.

Sirius A is approximately 10,000 times brighter than Sirius B, making it challenging to capture both in a single image using traditional sensors, as noted by Mark Norris from the University of Central Lancashire, UK, who was not part of the study.

According to Singh Thakur, neurotype cameras excel at tracking fast-moving objects due to their high frame rates. “For high-speed objects, you can capture their movement without blur, unlike conventional cameras,” he explains.

Telescopes typically utilize multiple sensors that can be swapped as needed. Norris points out that a neurotype camera could serve as an additional tool for viewing scenarios where both very bright and very faint objects need to be observed concurrently, or for quickly moving targets like the recently identified interstellar object 3i/Atlas.

Traditionally, to follow fast-moving objects, astronomers would need to pan the telescope. However, neurotype cameras can accurately track the movement of these objects precisely while maintaining background details and resolving their locations.

“Do you want to know the brightness of an object or its location? In quantum mechanics, you can’t ascertain both at the same instant,” Norris states. “This technology offers a potential method to achieve both simultaneously.”

While neurotype cameras provide unique advantages, they may not replace all sensor applications. Their resolution is typically lower than that of charge-coupled devices (CCDs), which are commonly used in digital cameras, achieving an efficiency of about 78% compared to the 95% efficiency of CCDs. This disparity makes traditional sensors more effective at capturing dim objects near their detection limits.

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Source: www.newscientist.com

Looking up in the city of stars: The Los Angeles Astronomical Club keeps searching

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LOS ANGELES – Los Angeles boasts the world’s most prominent celebrities, yet monthly gatherings reveal that the city’s affluent and renowned individuals have an interest in the cosmos.

The Silver Lake Star Party, organized by the Los Angeles Astronomical Association, started with a few telescopes in the heart of the city. It has evolved into a popular evening hangout. Members convene every Monley, welcoming hundreds of strangers to peek through their personal telescopes.

“It’s truly breathtaking,” remarked member Bobby Kabubaguestuk. “The allure, the thrill, the wonder of seeing Saturn, Jupiter, and the Orion Nebula for the first time.”

Children examining the telescope at the Outdoor Astronomy Club event in Los Angeles on April 18, 2025.
NBC News

Society aims to cultivate an interest in space. Despite the bustling urban setting not being an ideal location for stargazing, society members manage to make it work.

“Even in busy, densely populated, light-polluted areas, there is always something captivating in the night sky. It presents an opportunity to connect with the cosmos,” shared Cabbagestalk.

While some organizers are seasoned astronomers, others like Cabbagestalk are simply enthusiastic. They elucidate on what viewers observe through the telescope, identifying constellations and planets.

“These stars, planets, and the moon are present daily, yet we often overlook their magnificence,” reflected Cabbagestalk. “By coming here, people can slow down and gain a new perspective on the world and universe around them.”

This event is open to individuals of all ages, free of charge. All that is required is a willingness to gaze into the celestial wonders above.

Source: www.nbcnews.com