The Wide-field Imaging Survey Polarimeter


WISP is a suborbital rocket payload telescope built to obtain the first astronomical wide-field polarimetric images in the ultraviolet. The instrument has two broadband filters centered at 1640 Å and 2180 Å, an unbinned pixel size of 15 arcseconds, and a field of 5.0 x 1.7 degrees. Its mission is to observe several different reflection nebulae to constrain currently controversial UV scattering properties of interstellar grains, which once measured will be of interest in determining the UV background, modeling radiative transfer in star formation regions, and the study of active galaxies. The vacuum-UV is well-suited to reflection nebula ``polarimagery'', as the polarized background is low, and few stars are hot enough to be illuminators, making scattering paths more traceable than in the visible. Furthermore, dust grain polarization function angular dependences are well enough constrained that true scattering angles, and hence 3-D geometry, may be directly determined.

WISP Targets

The current WISP target list is:

Name R.A. Dec L B Comments Flight
M31 (Andromeda) 0.7 41 121 -22 EG; DGL
M45 (Pleiades) 3.7 24 167 -24 closest (130 pc) bright RN 3 Dec 94
LMC 5.7 -69 279 -32 EG; large angular size 20 Nov 95
M81/M82 9.9 70 141 40 Sandage DGL area; M82 knots 12 Apr 99
Lockman Window 10.7 58 151 52 DGL; extragalactic background
Draco Cloud 16.8 60 90 39 DGL; X-ray shadow
NGC 7000 21.0 44 85 -1 North America Nebula; large RN
NGC 7023 21.0 68 104 14 brightest RN; Witt study
Comet Hale-Bopp big and bright; 1.4 AU from Earth 8 Apr 97

RN = reflection nebula; DGL = diffuse galactic light; EG = external galaxy

WISP has flown four times, and all four flights were successful. Reduction of the Pleiades data has been completed, with results for the Large Magellanic Cloud to follow soon after. Observations of Hale-Bopp were made in spring 1997, and the M81/M82 region in Spring, 1999. If you can think of other targets we should add to our list, please let us know!

WISP scientific papers and Technical Documents

WISP People

The Principal Investigator is Ken Nordsieck. Other folks who are or have been involved in various ways include (in alphabetical order) Andrew Afflerbach, Chris Anderson, Andrew Cole, Sam Gabelt, Jay Gallagher, Steven Gibson, Walt Harris, Kurt Jaehnig, Tom Jones, Chuck Joseph, John Lemke, Pam Marcum, Don Michalski, Jim O'Donnell, and Dick Pfeifer. The project is operated through the UW-Madison Space Astronomy Laboratory.

WISP is supported by NASA grant NAG5-647.

This page is maintained by Ken Nordsieck.

This page has been accessed times since Oct 1, 1999.