Tag Archives: neighboring

Strange events occurring in close proximity to a neighboring galaxy

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The little Magellan Clouds (SMCs), a dwarf galaxy that is orbiting near our own Milky Way, appear to satisfy a rather dramatic ending.

That is the conclusion of a new study published in Astrophysical Journal Supplement Series astronomers have tracked over 7,000 large stars in SMC. Each one is more than eight times the size of our sun.

These star heavyweights burn a short life that lives bright and fast, providing clues about their own movements as well as their turbulent gas clouds.

And what researchers found was impressive. This former codbone universe’s neighbor is torn apart quite badly by the gravity of the large Magellan Cloud (LMC).

The milky stripes of this star-filled sky are two d-star galaxies visible only from the southern hemisphere – here is a small Magellan cloud photographed above the Delusional Observatory of Eso in Chile. -ESO/j. Corosimo

“SMCs are interacting galaxies that are coupled to the LMC by gravity.” Satoya Nakano the first author of the study said BBC Science Focus. “The stars on the side of the SMC near the LMC experience stronger gravity and are moving towards the LMC, but the stars experience even weaker pulls.”

This gravitational tug of war slowly pulls the SMC apart with possible nudges from our own Milky Way approaching about 200,000 light years away.

So why is this important?

For one, the team discovered that the SMC was not rotating the way astronomers had assumed. Spiral galaxies like our own usually rotate with stars and gas processing around the central axis. But not all galaxies are – and SMC may be one of them.

“The question of when rotational motion appears in galaxies is a very interesting topic among researchers,” Nakano said.

“SMC was considered a rotating galaxy, but this study shows that it is not actually rotating. It suggests that if even a nearby galaxy like SMC is misinterpreted, it requires much more attention when assessing galaxy rotations further away.”

The colours of the arrows represent the direction of the movement of the giant stars in the SMC. Compared to the LMC at the bottom left of the image, most red arrows show movement towards the LMC, while most light blue arrows show movement away from the LMC, suggesting that they are being pulled apart. – Satoya Nakano

And SMC is very close by space standards. Just 200,000 light years away, it is more than ten times closer to Andromeda, the nearest largest galaxy.

The lack of rotation not only changes our understanding of SMC’s structure, but also allows us to discard estimates of mass.

“The SMC is not rotating, so historical estimates of its mass may be incorrect.” Professor Tahara the author of another study said BBC Science Focus.

“The estimates of mass were born from previously estimated rotational motions. However, if these are not reliable, the estimates need to be revised. Without this, we cannot predict the future existence of SMC.”

Nakano and Tahara hope that detailed simulation observations to model the fate of the galaxy open the door. But for now, the future appears to be far from bright.

About our experts

Satoya Nakano is a doctoral candidate from the Faculty of Physics, Graduate School of Science, Nagoya University, Japan.

Tahara Sword He is an associate professor at Nagoya University Graduate School of Science, Japan. His research is Publications of the Japanese Astronomical Association, Astrophysical Journal and Astronomy and Astrophysics.

read more:

  • How do you know that the Milky Way is a spiral galaxy?
  • How many galaxies are there in the universe?
  • How Alien Galaxies Will Quickly Collide Ours

Source: www.sciencefocus.com

Possible discovery of extraterrestrial aurora on a neighboring collapsed star

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Brown dwarfs, often referred to as “failed stars,” are a fascinating type of celestial object. They are too large to be considered planets, yet too small to undergo the fusion process necessary to become fully-fledged stars.

One such brown dwarf, named WISEP J193518.59–154620.3 (or W1935 for short), is believed to be observable from Earth, especially towards the north and south poles. Astronomers suspect that it may exhibit an aurora similar to the mesmerizing aurora borealis, but on a much brighter scale.

Research featured in the journal Nature utilized NASA’s James Webb Space Telescope (JWST) to study W1935. This brown dwarf is relatively close to us in the galaxy, approximately 47 light-years away from Earth.

Upon pointing a space telescope the size of a tennis court towards the brown dwarf, researchers noticed a peculiar glow emanating from it.

“We were expecting to detect methane as it’s abundant in these brown dwarfs. However, instead of absorbing light, we found methane emitting light,” stated Dr. Jackie Faherty, the lead author of the study. “My initial reaction was, ‘What’s going on? Why is this object emitting methane?'”

Co-author Dr. Ben Burningham mentioned to BBC Science Focus that in the search for alien auroras in objects like W1935, astronomers traditionally focused on emissions from other gases found higher up in the object’s atmosphere.

“Methane emissions were not anticipated to be significant, but now it appears to be a significant factor,” he added.

Computer modeling of W1935 to elucidate the unusual methane emissions revealed a surprising temperature inversion, where the atmosphere gets warmer with increasing altitude. This phenomenon is common for planets orbiting stars but unexpected for an isolated object like W1935 without an apparent external heat source.

Further investigation led researchers to compare W1935 with Jupiter and Saturn from our solar system, which also exhibit methane emissions and temperature inversions.

The observed features in the solar system giants are attributed to auroras, luminous phenomena generated when energetic particles interact with the planet’s magnetic field and atmosphere.

Auroras are known to heat the upper atmosphere of planets, aligning with the researchers’ findings regarding W1935.

However, a missing element in the puzzle was the source of particles causing high-energy auroras in our solar system, which stem from the sun and travel as solar wind. Since W1935 is a rogue star without a host star, solar wind was ruled out as a possible explanation.

Scientists hypothesize that an undiscovered active satellite could be generating the alien aurora observed in W1935, akin to moons around Jupiter and Saturn that expel material into space enhancing the gas giants’ auroras.

“W1935 presents an intriguing expansion of solar system phenomena without any stellar illumination to clarify it,” Faherty remarked. “With Webb, we can delve into the chemistry and unravel the similarities or differences in auroral processes beyond our solar system.”

About our experts

Jackie Faherty is a senior scientist and education manager at the American Museum of Natural History, focusing on detecting and characterizing brown dwarfs and exoplanets. She advocates for increasing diversity in STEM fields through her unique outreach efforts.

Ben Burningham is an Associate Professor and Head of Outreach at the University of Hertfordshire, specializing in brown dwarfs, substellar objects, and superplanets. Burningham has contributed to research published in the Astrophysical Journal, Nature, and Astronomical Journal.

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Source: www.sciencefocus.com