UW-Madison astronomer leads effort to study creation of galaxies

November 3rd 2010 Simon Kuran
Natural & Physical Sciences
Back to News

Dr. Andy Sheinis, an assistant professor in Astronomy, has a saying, "Every proposal happens by design.  In reality, discovery happens by accident."

SALT
The South African Large Telescope, one of the largest optical telescopes in the world and the largest single optical telescope in the southern hemisphere. A new addition to the telescope has been created by UW-Madison Astronomy Professor Andy Sheinis.
Potential for unanticipated discovery is woven within the plans for a new addition to the Southern African Large Telescope (SALT), one of the largest optical telescopes in the world and the largest single optical telescope in the southern hemisphere.

SALT's addition comes in the form of a new spectrograph, an instrument used to study properties of light.

That new spectrograph is coming from a team at UW-Madison led by PI Sheinis and Project Scientist Dr. Marsha Wolf.

The new SALT instrument, known as the Robert Stobie Spectrograph, NIR Arm or RSS-NIR, is a $6.5 million upgrade to the telescope.  The one-ton instrument will be assembled within a frame roughly half the size of a Volkswagen Bug.

The detailed design for the RSS-NIR addition was approved and and the team was commended for an excellent design by an international panel during its Critical Design review in Madison on October 11-12th at the Pyle Center.

What SALT partners might discover with the RSS-NIR remains a mystery, but what Sheinis expects to find is exciting in its own right.  The instrument may help unlock mysteries surrounding the creation of galaxies.

Dr. Andy Sheinis
Dr. Andy Sheinis

It is thought that the center of nearly every galaxy contains a supermassive black hole. Astronomers observe a correlation between the mass of black holes and the range of velocities of stars clustered around them. There may be a connection between the formation of black holes and their host galaxies but an explanation for this correlation remains unsolved.

Small regions at the center of some galaxies that are especially luminous — Active Galactic Nuclei (AGN) – might provide answers to this mystery. A type of AGN called a Quasi Stellar Object (QSO) is of particular interest because of its unique qualities.

Astronomers using SALT will use the new RSS-NIR instrument to examine the relationship between gasses flowing toward the center of QSO black holes and surrounding stars. What scientists learn will help explain the origin and evolution of galaxies.

As an observer and instrument builder, Sheinis is in the minority among astronomers. He worked in industry as an optical engineer prior to a five-year stint at the Mees Solar Observatory in Hawaii. While overlooking Maui’s volcanic mountains he decided to take a pay cut to spend seven years earning a PhD at UC-Santa Cruz.

Sheinis used his unique expertise to leverage investments by UW-Madison, the National Science Foundation and SALT to develop RSS-NIR. It will increase the university’s approximately 15 percent share of the 525,600 total minutes available to SALT partners.

The project has been designed over the past 2 years and will be built during the next two: Sheinis hopes that RSS-NIR will take its rightful place above the SALT telescope by 2012.