About 430 million light years from Earth, in the Leo constellation, a new ultra-diffuse galaxy has been discovered to be under formation at the end of the tidal tail of galaxy NGC 3785.
Discovery Highlights:
- Galaxy NGC 3785:
- Known for having the longest tidal tail ever discovered, a feature formed due to gravitational (“tidal”) forces when galaxies interact closely.
- The tidal tail is a long, thin stream of stars and interstellar gas, pulled away during a close encounter or merger between galaxies.
- Ultra-Diffuse Galaxy Formation:
- An ultra-diffuse galaxy (UDG) is being formed at the end of NGC 3785’s tidal tail.
- This process is likely driven by the gravitational interaction between NGC 3785 and a neighboring galaxy.
- Significance of the Discovery:
- Marks a milestone in understanding how galaxies form and evolve.
- Provides insight into the role of gravitational interactions in creating new structures in the universe.
Background on Galaxies:
- Composition and Size:
- Galaxies consist of stars, planets, interstellar gas, and dust, all bound by gravity.
- Sizes range from small galaxies with a few thousand stars to massive ones containing trillions of stars, spanning up to a million light-years.
- Most large galaxies house supermassive black holes at their centers, with masses billions of times that of the Sun.
- Milky Way
- Our home galaxy is called the Milky Way.
- It’s a spiral galaxy with a disk of stars spanning more than 100,000 light-years.
- Earth is located along one of the galaxy’s spiral arms, about halfway from the center.
- Our solar system takes about 240 million years to orbit the Milky Way just once.
- Galactic Evolution:
- Galaxy interactions, including mergers and tidal forces, play a significant role in shaping galaxy structure and evolution.
- This discovery underscores how interactions can lead to the formation of new galaxies even in complex systems.
(Source: PIB & NASA)
