Credit: NASA/JPL-Caltech/C. Beichman (Caltech)

Is There Anybody Home?

NASA's Spitzer Space Telescope recently captured these infrared images of six older stars with known planets. The yellow, fuzzy blobs are stars circled by disks of dust, or "debris disks," like the one that surrounds our own Sun. Though astronomers had predicted that stars with planets would harbor debris disks, they could not detect such disks until now.

Spitzer was able to sense these dusty disks via their warm infrared glows. Specifically, the presence of the disks was inferred from an excess amount of infrared emission relative to what is emitted from the parent star alone.

The stars themselves are similar in age and temperature to our Sun. In astronomical terms, they are stellar main sequence stars, with spectral types of F, G, or K. These planet-bearing stars have a median age of four billion years. For reference, our Sun is classified as a G star, with an age of approximately five billion years.

The disks surrounding these planetary systems are comprised of cool material, with temperatures less than 100 Kelvin (-173 degrees Celsius). They are10 times farther away from their parent stars than Earth is from the Sun, and are thought to be analogues of the comet-filled Kuiper Belt in our solar system.

The contrast scale is the same for each image. The images are approximately 2 arcminutes on each side. North is oriented upward and east is to the left. The pictures were taken with the 70-micron filter of Spitzer's multiband imaging photometer. The telescope resolution at 70 microns is 17 arcseconds and there is no evidence for any emission extended beyond the telescope resolution.

About the Object	Object Name: HD 117176 (70 Vir) Object Type: G2.5Va star Position (J2000): RA: 13 28 25.81 Dec: +13 46 43.6 Distance: 54 light-years Constellation: Virgo
About the Data	Spitzer Image Image Credit: NASA/JPL-Caltech/C. Beichman (Caltech) Instrument: MIPS Release Date: 12/09/04
Observers	Charles Beichman (Caltech)

About the Object	Object Name: HD 33636 Object Type: G0 star Position (J2000): RA: 05 11 46.45 Dec: +04 24 12.7 Distance: 94 light-years Constellation: Orion
About the Data	Spitzer Image Image Credit: NASA/JPL-Caltech/C. Beichman (Caltech) Instrument: MIPS Release Date: 12/09/04
Observers	Charles Beichman (Caltech)

About the Object	Object Name: HD 52265 (HR2622) Object Type: G0III-IV star Position (J2000): RA: 07 00 18.04 Dec: -05 22 01.8 Distance: 92 light-years Constellation: Monoceros
About the Data	Spitzer Image Image Credit: NASA/JPL-Caltech/C. Beichman (Caltech) Instrument: MIPS Release Date: 12/09/04
Observers	Charles Beichman (Caltech)

About the Object	Object Name: HD 82943 Object Type: G0 star Position (J2000): RA: 09 34 50.74 Dec: -12 07 46.4 Distance: 90 light-years Constellation: Hydra
About the Data	Spitzer Image Image Credit: NASA/JPL-Caltech/C. Beichman (Caltech) Instrument: MIPS Release Date: 12/09/04
Observers	Charles Beichman (Caltech)

About the Object	Object Name: HD 50554 (BD+241451) Object Type: F8V star Position (J2000): RA: 06 54 42.83 Dec: +24 14 44.0 Distance: 100 light-years Constellation: Gemini
About the Data	Spitzer Image Image Credit: NASA/JPL-Caltech/C. Beichman (Caltech) Instrument: MIPS Release Date: 12/09/04
Observers	Charles Beichman (Caltech)

About the Object	Object Name: HD 128311 (GJ3860) Object Type: K0 star Position (J2000): RA: 14 36 00.56 Dec: +09 44 47.5 Distance: 54 light-years Constellation: Boöaut;tes
About the Data	Spitzer Image Image Credit: NASA/JPL-Caltech/C. Beichman (Caltech) Instrument: MIPS Release Date: 12/09/04
Observers	Charles Beichman (Caltech)

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.