'3000-light-years away': ESA discovers 21 exploded stars orbiting our sun-like stars in deep space
Produced by: Tarun Mishra
Rare Celestial Pairings
Astronomers, led by Caltech's Kareem El-Badry, have identified what could be 21 neutron stars orbiting stars similar to our sun—a rare discovery in the universe where most stars are found in pairs.
Neutron Stars Defined
Neutron stars are dense remnants of massive stars that have exploded, typically invisible on their own but detectable when they orbit a sun-like star. Their gravitational pull causes the companion star to wobble, revealing their presence.
Utilizing Gaia Mission
The discovery relied on the European Space Agency's Gaia mission, which continuously scans the sky and measures stellar movements. This capability enabled astronomers to detect subtle gravitational effects indicating the presence of neutron stars.
Follow-Up Observations
Data from ground-based telescopes like W. M. Keck Observatory, La Silla Observatory, and Whipple Observatory complemented Gaia's findings. These observations provided insights into the masses and orbital dynamics of the neutron stars.
Distinct Characteristics
Unlike previously known neutron star systems, which are compact and exhibit mass transfer, these newly discovered systems feature wider orbits—about one to three times the distance between Earth and the sun—rendering them quiescent and dark.
Gravitational Effects
These neutron stars were detected solely through their gravitational influences, indicating they are not actively accreting material from their companions, unlike closer neutron star systems.
Formation Mysteries
The origins of these binary systems remain unclear. The progenitor stars of neutron stars likely interacted with sun-like stars during their evolution, possibly engulfing and later exploding in a supernova, dispersing the binaries in opposite directions.
Credit: ALMA (ESO/NAOJ/NRAO)
Gaia's Sensitivity
Gaia's sensitivity to wide orbits and long orbital periods, ranging from six months to three years, was crucial in identifying these rare pairings within 3,000 light-years of Earth.
Implications and Future Studies
The rarity of these neutron star and sun-like star pairings challenges current models of binary star formation. Further discoveries and comparisons with theoretical predictions will enhance understanding of how such exotic stellar systems evolve and survive in the cosmos.