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cosmos, space, Universe

Unveiling the Secrets of K2-18 b: The James Webb Space Telescope’s Intriguing Findings on a Distant Exoplanet

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The James Webb Space Telescope (JWST) has given astronomers and scientists a new perspective on life beyond Earth. NASA confirmed in a recent release that the telescope had identified possible signs of life emanating from K2-18 b, an Earth-like exoplanet that is 8.6 times the mass of our planet.

The Enigmatic K2-18 b

K2-18 b is not just another exoplanet in the vast universe; it lies 120 light-years from Earth in the constellation Leo. This celestial body orbits in what is known as the “habitable zone” of its host star, a cooler dwarf star named K2-18. The planet is categorized as a “Mini-Neptune,” which presents a particular enigma for astronomers because it does not resemble any planetary bodies in our solar system.

Intriguing Observations

What makes the recent JWST investigation so remarkable are the findings related to the composition of K2-18 b’s atmosphere. Researchers found “carbon-bearing molecules,” including methane and carbon dioxide. Such discoveries are significant because they add weight to the theory that K2-18 b could be a Hycean exoplanet with a hydrogen-rich atmosphere and potentially a water-covered surface.

The James Webb Space Telescope’s observations go beyond confirming existing theories. NASA reported the possible detection of a molecule known as dimethyl sulfide (DMS). Only life on Earth can produce this molecule, and phytoplankton in marine environments is where most of the DMS in Earth’s atmosphere comes from.

Changing the Narrative

It was just in 2019 that NASA’s Hubble Space Telescope first investigated K2-18’s atmosphere, and those initial studies already had significant implications. “Our findings underscore the importance of considering diverse habitable environments in the search for life elsewhere,” stated Nikku Madhusudhan, the lead author of the paper announcing these new results and an astronomer at the University of Cambridge.

Looking Ahead

According to team member Savvas Constantinou, also of the University of Cambridge, the discoveries are based on just two observations of K2-18 b. “This means our work here is but an early demonstration of what Webb can observe in habitable-zone exoplanets,” he explained. As the James Webb Space Telescope continues to peer into the far reaches of space, scientists hope for more insights that could fundamentally reshape our understanding of life beyond Earth.

Conclusion

The recent findings about K2-18 b create a ripple effect in the scientific community. While the search for life in the universe has always been a subject of interest, discoveries like these reignite the conversation and fuel the imagination. If nothing else, the observations made by the JWST highlight the vast possibilities that await us in the unexplored corners of our universe.

Cited Works:
Shannon, Bill. “James Webb Telescope Stumbles Upon Signs of Possible Life on an Earth-like Planet.” NewsNation, September 13, 2023. https://www.newsnationnow.com/space/james-webb-telescope-stumbles-onto-signs-of-possible-life-on-earth-like-planet/?fbclid=IwAR16ML0LF0PFDduPnJYtS6opGujHoFXUAszne7S1SYvvMST5bsaEFyLgv2c.

cosmos, Humankind, Science, space, Universe

Is the discovery of black holes emitting radio waves long after devouring stars a groundbreaking revelation that challenges our understanding of these cosmic entities, or does it merely raise more questions about the mysteries of the universe?

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Introduction:
In the vast cosmos, some of the most breathtaking phenomena occur when stars meet their formidable cosmic neighbors, supermassive black holes. The dramatic events that unfold during these encounters have long fascinated astronomers and astrophysicists. Until recently, it was widely believed that the spectacle surrounding such collisions faded away within weeks or months. However, a new revelation has left the scientific community astounded: black holes might have a case of cosmic indigestion, emitting radio waves hundreds of days after devouring a star. Join us as we explore this intriguing cosmic phenomenon.

The Unexpected Discovery:
An international team of astrophysicists has upended our understanding of black hole behavior. They observed radio waves emanating from the vicinity of supermassive black holes, long after these celestial giants had torn apart nearby stars. The implications are profound, suggesting that a significant portion of black holes indulges in a post-feast ritual of ‘burping’ material, and this phenomenon occurs years after the initial star-shredding event. Lead author Yvette Cendes remarks, “No one was expecting this, and we don’t really understand why this might be!”

Unveiling the Mystery:
The research relied on data collected from three powerful radio telescopes: the Very Large Array in the United States, MeerKAT in South Africa, and the Australian Telescope Compact Array. The team meticulously studied 24 supermassive black holes, and their findings, while yet to be peer-reviewed, are available on the pre-print server arxiv.org for the scientific community to explore.

Tidal Disruption Events:
To comprehend this phenomenon, it’s essential to revisit the concept of tidal disruption events. When a star ventures too close to a supermassive black hole, its immense gravitational pull elongates the star into a spaghetti-like structure. In a matter of hours, the star is torn apart, resulting in one of the most brilliant optical flares observed in the Universe. Approximately 20 to 30 percent of these events produce early-stage radio waves. However, researchers typically shift their focus elsewhere after witnessing the initial bright light.

The ‘Jetty’ Surprise:
A groundbreaking discovery last year by Yvette Cendes and her team changed the game. They identified a supermassive black hole, twenty million times more massive than the Sun, emitting jets of radio waves approximately three years after consuming a star. This revelation, nicknamed ‘Jetty McJetface’ or simply ‘Jetty,’ challenged conventional thinking. Cendes ponders, “Jetty was just one of 24 tidal disruption events we were studying… What the heck were the rest of them doing?!”

The Universe: Dangerous Black Holes and Gamma Ray Bursts (S1, E12) | Full Episode

Black Holes: Cosmic Mess-Makers:
Contrary to popular perception, black holes do not consume stars like vacuum cleaners. Instead, they create a cosmic mess, akin to the Cookie Monster devouring cookies. Only a fraction of the stellar material falling into a black hole crosses the event horizon, where not even light can escape. The remaining material is ejected into the galaxy or forms an orbiting debris cloud known as the accretion disc.

Two Possible Explanations:
The authors of the study propose two potential reasons why radio waves might emanate from black holes long after star collisions. One theory suggests that it takes time for the debris encircling the black hole to settle into a stable orbit. The other posits that the debris, loosely bound to the supermassive black hole, forms a spherical envelope that must cool and contract significantly to create an accretion disc. This cooling process might lead to delayed radio wave emissions, offering an alternative explanation for this captivating cosmic phenomenon.

Conclusion:
The revelation of black holes emitting radio waves long after star encounters challenges our understanding of these enigmatic cosmic entities. It invites further exploration into the intricate dynamics of black hole behavior and their intricate relationships with the stars they encounter. As scientists delve deeper into the mysteries of the cosmos, we may uncover even more unexpected cosmic phenomena that reshape our perception of the Universe.

Cited Works:

Maes, Christian. Facts of Matter and Light: Ten Physics Experiments that Shaped Our Understanding of Nature. Springer Nature, 2023.

Gbur, Gregory J. Invisibility: The History and Science of How Not to Be Seen. Yale University Press, 2023.

Henderson, Caspar. A Book of Noises: Notes on the Auraculous. University of Chicago Press, 2023.

Black Holes ‘Burp’ Years After Shredding Stars, And We Don’t Know Why. https://www.sciencealert.com/black-holes-burp-years-after-shredding-stars-and-we-dont-know-why?fbclid=IwAR0d04gSQvrKHFVAAQLWvLu_Ndpuv0NufryX_81ncMqJMuf5hsD_0WbZ7Zs