Credit: NASA/JPL-Caltech/M. Kuchner (GSFC)

Evidence for Comets Found in Dead Star's Dust

This graph of data, or spectrum, from NASA's Spitzer Space Telescope indicates that a dead star, or white dwarf, called G29-38, is shrouded by a cloud of dust. The data also demonstrate that this dust contains some of the same types of minerals found in comet Hale-Bopp.

The findings tell a possible tale of solar system survival. Though the dust seen by Spitzer is likely from a comet that recently perished, its presence suggests that an icy distant ring of comets may still orbit the dead star.

These data were collected by Spitzer's infrared spectrometer, an instrument that cracks light open like a geode, revealing its coveted components. In this spectrum, light from the white dwarf is on the left, at ultraviolet and visible wavelengths. The spectrum on the right, at infrared wavelengths longer than about 2 microns, shows much more light than can be explained by a white dwarf alone. The bump seen around a wavelength of 10 microns offers a clue to the source of this excess infrared light. It signifies the presence of silicate minerals, which are found in our own solar system on Earth, in sandy beaches, and in comets and asteroids. These silicate grains appear to be very small like those in comets, so astronomers favor the theory that a comet recently broke apart around the dead star.

About the Object	Object Name: G29-38 Object Type: White Dwarf Position (J2000): RA: 23h 28m 47.74s Dec: +05¡ 14' 53.4" Distance: 14 pc Constellation: Pisces
About the Data	Image Credit: NASA/JPL-Caltech/M. Kuchner (Goddard Space Flight Center) Instrument: IRAC, MIPS, and IRS Wavelength: 4.5 microns, 8.0 microns, 24 microns, and 5.5-14 microns Exposure Date: IRAC: 2004 November 26 10:54 UT MPS: 2004 December 2 04:45 UT IRS: 2004 December 8 3:26 UT Exposure Time: RAC: 30 s MPS: 420 s IRS: 10 min Release Date: January 11, 2006
Observers	Marc J. Kuchner (Goddard Space Flight Center) William T. Reach (Spitzer Science Center) Ted von Hippel (University of Texas at Austin) Adam Burrows (University of Arizona) Fergal Mullally (University of Texas at Austin) Mukremin Kilic (University of Texas at Austin) D. E. Winget (University of Texas at Austin)

The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory. This website is maintained by the Spitzer Science Center, located on the campus of the California Institute of Technology and part of NASA's Infrared Processing and Analysis Center.