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+--- Thread: Why Uranus & Neptune have different blue hues + Dipole repeller + Space triangle (/thread-12337.html)
Why Uranus & Neptune have different blue hues + Dipole repeller + Space triangle - C C - May 31, 2022
Scientists know why the planet and Neptune are different hues of blue
https://www.eurekalert.org/news-releases/954407
INTRO: Astronomers may now understand why the similar planets Uranus and Neptune are different colors. Using observations from the Gemini North telescope, the NASA Infrared Telescope Facility, and the Hubble Space Telescope, researchers have developed a single atmospheric model that matches observations of both planets. The model reveals that excess haze on Uranus builds up in the planet’s stagnant, sluggish atmosphere and makes it appear a lighter tone than Neptune... (MORE - details)
Based on the preprint version of 3 months ago ... https://youtu.be/3-RZ9T0ZEZ0
A mysterious intergalactic force is pushing against the Milky Way
https://www.space.com/dipole-repeller-mystery-beyond-galaxy
INTRO: It sounds like the premise of a bad sci-fi movie: There's some mysterious entity, beyond the boundaries of our galaxy, that is pushing against us with incredible force. We don't know exactly what it is, and we don't know how long it's been there. But we do know its name: the dipole repeller.
The name may be a bit dorky, but it's a very real thing. It's also nothing to worry about — just a normal consequence of the usual process of structure formation that's been happening in the universe for [checks watch] 13.8 billion years... (MORE - details)
Meet the dipole repeller. ... https://youtu.be/ciud4O5KAUw
Galaxy Collision Creates 'Space Triangle' in New Hubble Image
https://www.nasa.gov/image-feature/goddard/2022/galaxy-collision-creates-space-triangle-in-new-hubble-image
INTRO: A spectacular head-on collision between two galaxies fueled the unusual triangular-shaped star-birthing frenzy, as captured in a new image from NASA’s Hubble Space Telescope. The interacting galaxy duo is collectively called Arp 143. The pair contains the glittery, distorted, star-forming spiral galaxy NGC 2445 at right, along with its less flashy companion, NGC 2444 at left.
Astronomers suggest that the galaxies passed through each other, igniting the uniquely shaped star-formation firestorm in NGC 2445, where thousands of stars are bursting to life on the right-hand side of the image. This galaxy is awash in starbirth because it is rich in gas, the fuel that makes stars. However, it hasn’t yet escaped the gravitational clutches of its partner NGC 2444, shown on the left side of the image. The pair is waging a cosmic tug-of-war, which NGC 2444 appears to be winning. The galaxy has pulled gas from NGC 2445, forming the oddball triangle of newly minted stars.
“Simulations show that head-on collisions between two galaxies is one way of making rings of new stars,” said astronomer Julianne Dalcanton of the Flatiron Institute’s Center for Computational Astrophysics in New York and the University of Washington in Seattle. “Therefore, rings of star formation are not uncommon. However, what’s weird about this system is that it’s a triangle of star formation. Part of the reason for that shape is that these galaxies are still so close to each other and NGC 2444 is still holding on to the other galaxy gravitationally. NGC 2444 may also have an invisible hot halo of gas that could help to pull NGC 2445’s gas away from its nucleus. So they’re not completely free of each other yet, and their unusual interaction is distorting the ring into this triangle.”
NGC 2444 is also responsible for yanking taffy-like strands of gas from its partner, stoking the streamers of young, blue stars that appear to form a bridge between the two galaxies... (MORE - details)
https://youtu.be/bcEqD1NVvws