Daniel and Kelly’s Extraordinary Universe How many rogue planets and stars are there?
Dec 18, 2025
Explore the mysterious world of rogue planets and stars, diving into how they form and get ejected from their systems. Discover the mechanisms behind star formation and the role of dark matter in creating galaxies. Learn about hypervelocity stars and how intergalactic supernovae occur. With billions of rogue planets likely existing in our galaxy, ponder the possibility of life thriving on these isolated worlds, fueled by geothermal heat. Join in on this fascinating cosmic journey!
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Stars And Planets Start In Galactic Nurseries
- Stars and planets form in dense clouds inside galaxies, not in empty intergalactic space.
- Dark matter's gravity seeds galaxy and star formation by collecting gas into halos.
How Stars Become Hypervelocity Rogues
- Galaxies hold stars by gravity, so ejecting a star requires a huge velocity boost.
- Mergers and supermassive black holes can kick stars out as hypervelocity intergalactic wanderers.
S5 HVS1: A Star On The Run
- Daniel describes S5 HVS1, a star moving at nearly 2,000 km/s likely boosted from the galactic center.
- Its trajectory suggests it will escape the Milky Way unless deflected.