Updated
Updated · Space.com · Jul 15
Astronomers Uncover 4 Hidden White Dwarfs Within 65 Light-Years as Hubble Tracks Red Dwarf Wobbles
Updated
Updated · Space.com · Jul 15

Astronomers Uncover 4 Hidden White Dwarfs Within 65 Light-Years as Hubble Tracks Red Dwarf Wobbles

3 articles · Updated · Space.com · Jul 15

Summary

  • Four white dwarfs hidden by brighter red dwarf companions were identified within about 65 light-years of Earth, marking the first such nearby binary detections; one ranks as the ninth-closest white dwarf to the solar system.
  • Hubble ultraviolet observations confirmed the stars after astronomers noticed radial-motion "wobbles" in the red dwarfs, using custom calibration to separate true white dwarf signals from red-dwarf glare.
  • G 203-47, just 25 light-years away, stood out because its red dwarf rotates roughly every 100 days while orbiting the white dwarf every 15 days, defying the tidal locking seen in similar systems.
  • The find matches predictions of roughly 4 to 5 close white dwarf-red dwarf pairs within 65 light-years, supporting current population models and suggesting another 9 to 10 such binaries may still be undiscovered.

Insights

How can a 36-year-old Hubble still spot hidden stars in the glare of their companions?
Are 'dynamical fossil' star systems like G 203-47 rewriting the rules of stellar evolution?
What other cosmic ghosts are lurking, undiscovered, in our stellar neighborhood?