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#astrophysics

68 posts27 participants7 posts today
Public
Dr. John Barentine FRAS

JWST just keeps dropping bangers this week.

This image is of a galaxy in a cluster called SMACSJ0028.2-7537. But it's a two-fer, courtesy of general relativity: "What at first appears to be a single, strangely shaped galaxy is actually two galaxies that are separated by a large distance. The closer foreground galaxy sits at the center of the image, while the more distant background galaxy appears to be wrapped around the closer galaxy, forming a ring."

The apparent 'wrapping' of the background spiral galaxy results from the gravity of the foreground elliptical galaxy. It warps the space (and time) around it, changing the paths taken by light from the background object, creating a funhouse mirror effect. In honor of the theorizer of general relativity, these configurations are called 'Einstein rings'.

More info: esawebb.org/images/potm2503a/

📷: ESA/Webb, NASA & CSA, G. Mahler

In the centre is an elliptical galaxy, seen as an oval-shaped glow around a small bright core. Around this is wrapped a broad band of light, appearing like a spiral galaxy stretched and warped into a ring, with bright blue lines drawn through it where the spiral arms have been stretched into circles. A few distant objects are visible around the ring on a black background.
#Astronomy#Astrophysics#Physics
Public
Dr. John Barentine FRAS

New JWST image just dropped.

This object is called Herbig-Haro 49/50. It's the outflow of a still-forming star hidden from view to the lower right of the orangish cone of material oriented diagonally in this image.

As stars form they eject excess matter in the direction of their poles of rotation. That material encounters the interstellar medium in the vicinity and lights up in response. "Like the wake of a speeding boat, the bow shocks in this image have an arc-like appearance as the fast-moving jet from the young star slams into the surrounding dust and gas."

Purely by coincidence, the outflow lines up with a distant background galaxy, which is the circular pinkish/blue object at upper left.

More info about the image: science.nasa.gov/missions/webb

NASA’s James Webb Space Telescope observed Herbig-Haro 49/50, an outflow from a nearby still-forming star, in high-resolution near- and mid-infrared light. The intricate features of the outflow, represented in reddish-orange color, provide detailed clues about how young stars form and how their jet activity affects the environment around them. Like the wake of a speeding boat, the bow shocks in this image have an arc-like appearance as the fast-moving jet from the young star slams into the surrounding dust and gas. A chance alignment in this direction of the sky provides a beautiful juxtaposition of this nearby Herbig-Haro object with a more distant spiral galaxy in the background. Herbig-Haro 49/50 gives researchers insights into the early phases of the formation of low-mass stars similar to our own Sun. In this Webb image, blue represents light at 2.0-microns (F200W), cyan represents light at 3.3-microns (F335M), green is 4.4-microns (F444W), orange is 4.7-microns (F470N), and red is 7.7-microns (F770W). Credit: NASA, ESA, CSA, STScI
#Astronomy#Stars#StarFormation
Public
Project Gutenberg

A Century Ago, Pioneering Astrophysicist Cecilia Payne-Gaposchkin Showed Us What Stars Are Made Of

The trailblazing Harvard scientist, who documented the dominance of hydrogen and helium in stars, is still inspiring researchers today

By Elizabeth Landau

smithsonianmag.com/science-nat

Stellar Atmospheres is available at PG:
gutenberg.org/ebooks/73996

Photograph of Cecilia Payne-Gaposchkin (1900-1979) at Harvard College Observatory Local number: SIA Acc. 90-105 [SIA2009-1326] Taken during the early to mid-20th century, the image portrays Payne-Gaposchkin in a thoughtful pose, dressed in a modest sweater, with natural light softly illuminating her face. In the background, shelves and filing cabinets filled with papers and scientific documents suggest an academic setting deeply immersed in research and discovery.
#books#astrophysics#womeninStem
Public
Flipboard Science Desk

How will the universe end? A changing understanding of dark energy may provide a new answer.

@AssociatedPress reports: "The big question is whether this dark energy is a constant force, which scientists have long thought, or whether the force is weakening, a surprising wrinkle tentatively proposed last year."

flip.it/s6j4.C

This image provided by NSF’s NOIRLab shows the trails of stars above Kitt Peak National Observatory, where a telescope is mapping the universe to study a mysterious force called dark energy. (NSF’s NoirLab via AP)
AP News · How will the universe end? A changing understanding of dark energy may provide a new answerBy Adithi Ramakrishnan
#Space#Physics#Astrophysics
Public
Prof Heino Falcke

My colleague Michael Wondrak has conducted an evaporation experiment of Ferrero-Rocher chocolate confection and compared it to our predictions for evaporation via a Hawking-like gravitational pair production, that we published recently ui.adsabs.harvard.edu/abs/2024

Unfortunately, the results don’t quite match the theory. Evaporation happened much quicker. Not sure why 🤔.

A graph illustrating the relationship between the lifetime (τ) in years and density (ρ) in grams per cubic centimeter. Key points represent various astronomical objects and phenomena, including dark matter, a human body, planets, and different types of stars, and a piece of chocolate.
The image features a theoretical background on an experiment regarding Rocher evaporation, discussing the Hawking and Schwinger effects in relation to particle production. Two images are presented: one shows a bowl of chocolate treats and the other contains handwritten notes about the experiment.
An image featuring text from a research paper discussing the results and conclusions related to "Rocher matter" and its decay over time, including future plans for experiments. References to theoretical background and publication details are also included.
#astrodon#physics#hawkingradiation
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