White Dwarf Stars in Open Cluster NGC 6791
NASA, ESA, and L. Bedin (STScI) · Download full size image
In studying the dimmest burned-out stars in globular star cluster NGC 6791, NASA's Hubble Space Telescope has uncovered a paradox: three different populations of stars exist in an object where all the stars should have formed at the same time out of an interstellar cloud of gas and dust.
[Left] — This is a ground-based telescopic view of NGC 6791, located 13,300 light-years away in the constellation Lyra. The green inset box shows the view with Hubble's Advanced Camera for Surveys.
[Top right] — The full Hubble Advanced Camera for Surveys field is full of stars estimated to be 8 billion years old. Two background galaxies can be seen at upper left.
[Bottom right] — A blow up of view of a small region of the Advanced Camera for Surveys field reveals very faint white dwarfs. The blue circles identify hotter dwarfs that are 4 billion years old. The red circles identify cooler dwarfs that are 6 billion years old.
Posted on: 10 Jul, 2008- Hubble Space Telescope
- Chandra X-ray Observatory
- Compton Gamma-Ray Observatory
- ROSAT X-ray Observatory
- SOHO Solar Observatory
- WMAP
- 2MASS Sky Survey
- ASTER Earth Imaging Instrument
- MISR Earth Imaging Instrument
- NRAO Gallery
- NAOJ Subaru Telescope
- Galaxy Evolution Explorer (GALEX)
- European Southern Observatory (ESO)
- Wide-Field Imager (WFI)
- SOFI Infrared Multi-mode Instrument
- Canada-France-Hawaii Telescope (CFHT)
- New Technology Telescope (NTT)
- Atacama Pathfinder Experiment (APEX)
- SOHO Daily Images - 1996
- Spitzer Space Telescope (SIRTF)
- Infrared Legacy Gallery




















































































































































































































































































































































