WHAM Sky Survey: Public Release

Mar 17, 2017

A velocity-integrated, all-sky view of the WHAM-SS.

A team of scientists led by UW Astronomy's Matt Haffner has released the deepest kinematic survey of our Galaxy's ionized gas. Inspiried through decades of research by Emeritus Professor Ron Reynolds, the Wisconsin H-Alpha Mapper (WHAM) records spectra from very faint emission in the interstellar medium, the pervasive gas and dust that fuels star formation and is imprinted with their energy outputs. WHAM was developed, built, and tested in Wisconsin during the mid-1990s with help from UW's Physical Sciences Lab and Space Astronomy Lab (now Washburn Astronomical Laboratories). In 1997, WHAM was transported to Kitt Peak in Arizona to begin its research in earnest. After an 11-year observing run, it was brought back to Wisconsin in 2008 for renovation before being moved to Cerro Tololo in Chile. Relocation to the southern hemisphere gave WHAM researchers the ability to observe a part of the sky that is hidden from northern-hemisphere telescopes. Despite its globetrotting, observers run WHAM from the comforts of their offices as WHAM was one of the first remotely-controlled astronomical facilities when it began operations. Today, WHAM continues to provide unique research opportunities from Chile for Wisconsin students, scientists, and their collaborators thanks to ongoing funding from the National Science Foundation

WHAM observing at night in ChileWhile WHAM can study emission from many different elements, the Sky Survey (WHAM-SS) focuses on the location and motions of ionized hydrogen throughout the Milky Way. By capturing spectra instead of images, WHAM can identify and study the dynamics of nebulae, filaments, and distant gas clouds in the halo of the Galaxy. Aided by the rotation of the Galaxy around its center, the WHAM-SS also allows researchers to isolate and trace individual spiral arms to large distances and impressive heights above the Galactic plane. This new, complete view of the ionized gas in the Milky Way helps our understanding of the complex, multi-phase interstellar medium and its role in the lifecycle of galaxies.

Explore more about WHAM and the WHAM-SS release.

UW-Madison Astronomy Home