Paul Kalas

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Paul Kalas (born August 13, 1967) is an astronomer known for his discoveries of circumstellar debris disks (i.e. debris disks around stars).

Contents 1 Background 2 Discoveries 3 References 4 External links

[edit] Background

Kalas was born in New York to George and Maria Kavallinis, who immigrated to the United States from Heraklion, Crete. Kalas attended Detroit Country Day School in Michigan, and studied Astronomy and Physics at the University of Michigan, Ann Arbor. He earned a Ph.D in Astronomy in 1996 from the University of Hawaii, under the direction of astronomer David Jewitt. Kalas worked as a postdoctoral scientist at the Max Planck Institute for Astronomy in Heidelberg, Germany, the Space Telescope Science Institute, and the University of California, Berkeley. He became an Adjunct Professor of Astronomy at the University of California at Berkeley in 2006.

Kalas lives with his wife Aspasia Gika and daughters Maria-Nikoleta and Natalia in Berkeley, California.

[edit] Discoveries

Kalas discovered several circumstellar disks using a coronagraph on the Hubble Space Telescope and at the University of Hawaii 2.2m telescope at Mauna Kea, Hawaii. In 1995 he discovered various forms of asymmetric structure in optical images of the Beta Pictoris disk. He was the lead scientist for the first optical images of debris disks surrounding the nearby red dwarf AU Microscopii and the bright star Fomalhaut. Kalas' Hubble Space Telescope image of Fomalhaut revealed a narrow belt of dusty material analogous to the solar system's Kuiper Belt. However, Kalas also found that Fomalhaut's belt is narrow and geometrically offset from the star by 15 astronomical units. These features are considered strong evidence for an extrasolar planet orbiting Fomalhaut that gravitationally sculpts the morphology of the belt.

Circumstellar disks discovered: 4

AU Microscopii	October 14, 2003	Ref. [3]
Fomalhaut	May 17, 2004	Ref. [2]
HD 53143	September 11, 2004	Ref. [1]
HD 139664	October 14, 2004	Ref. [1]

[edit] References

[1] Kalas, P., Graham, J.R., Clampin, M.C. & Fitzgerald, M. "First scattered light images of debris disks around HD 53143 and HD 139664", 2006, The Astrophysical Journal, Vol. 635, pp. L57 - L60 | doi: 10.1086/500305

[2] Kalas, P., Graham, J.R. & Clampin, M. "A planetary system as the origin of structure in Fomalhaut's dust belt," Nature, 2005, Vol. 435, pp. 1067-1070 | doi: 10.1038/nature03601

[3] Kalas, P., Liu, M.C. & Matthews, B.C. "Discovery of a large dust disk around the nearby star AU Microscopii," Science, 2004, Vol. 303, pp. 1990-1992 | doi: 10.1126/science.1093420

[4] Kalas, P. & Jewitt, D. "Asymmetries in the Beta Pictoris dust disk," 1995, The Astrophysical Journal, Vol. 110, pp. 794 - 804 | doi: 10.1086/117565

[5] Kalas' homepage

[edit] External links

• The Circumstellar Disk Learning Site
• Kalas' homepage
• Sky & Telescope Article on Fomalhaut discovery
• Space.com article on AU Microscopii discovery
• New Scientist article on HD 53143 and HD 139664 discoveries