Boosting solar physics

The DKI solar telescope under construction in Maui

By Travis Metcalfe

Shortly after the financial crash of 2008, Congress passed the American Recovery and Reinvestment Act (ARRA) to stimulate the economy with $787 billion in government spending on public infrastructure. Although controversial at the time, ARRA was later credited with saving or creating millions of jobs during the Great Recession. The National Solar Observatory (NSO) received $146 million in ARRA funding to help build the largest solar telescope in the world on a mountaintop in Maui, a $344 million project that may not have moved forward without the stimulus. The investment sparked a chain of events that ultimately moved NSO staff from Arizona and New Mexico to the new headquarters in Boulder this year.

The Advanced Technology Solar Telescope (ATST) was nearing its final design review in early 2009, after more than six years of development. Federal science funding had been slowly declining since 2004, so it was unclear whether construction of a large new facility would be feasible. The National Science Foundation (NSF) was already planning to shut down some older solar telescopes. With ATST moving forward, the NSO decided to consolidate its operations to one site. In early 2010, they issued a request for proposals to host the new headquarters. The University of Colorado Boulder was one of seven organizations to respond, and in late 2011 our city was selected over the other finalist in Huntsville, Alabama.

Boulder has been a national hub for solar physics since Harvard astronomer Walter Orr Roberts founded the High Altitude Observatory (HAO) in 1940. Our first solar observatory was absorbed into NCAR when it was established 20 years later. With the announcement in 2011 that Boulder would soon be home to a second solar observatory, local scientists wondered how long it would take members of Congress to call for a merger of the two organizations. The role of NCAR in climate science made it particularly vulnerable, with numerous politicians looking for ways to slash the budget. The relocation of NSO to Boulder may have been seen as an unprecedented opportunity to cut out a portion of NCAR and give it to solar physicists whose research had less political impact. So far, the concerns have been unwarranted.

With ATST under construction in Maui, the NSF wanted to inspire a new generation of solar physicists to enter the field. Hosting the NSO headquarters at a university was a strategic decision. Historically, most solar physicists worked at federally funded laboratories rather than universities. As a consequence, relatively few students were being trained in the field, and the demographics of solar physics meetings started to resemble a retirement seminar. The NSF subsidized the creation of faculty positions in solar physics across the country, and the University of Colorado enticed the NSO to relocate to Boulder in part by promising to hire several new faculty positions related to solar physics.

“By bringing in students, I think we will be able to support NSO in a way that would not have been possible in other cities,” says Axel Brandenburg, visiting professor in the Department of Astrophysical and Planetary Sciences at CU. Brandenburg first came to Boulder in 1992 to work as a postdoctoral fellow in the High Altitude Observatory at NCAR. He has spent the past 15 years working at research laboratories in Denmark and Sweden, but he jumped at the chance to return to Boulder last year for a rotating three-year faculty position in solar physics, created by CU as part of their agreement with the NSO. Earlier this month the university hosted a solar physics meeting for the American Astronomical Society. “The overall attendance was dominated by young people,” Brandenburg says, suggesting that the plan is already working.

Construction of the new telescope in Maui has encountered some resistance from native Hawaiian groups. Although several telescopes were already on the site, the peak where ATST would be located was considered sacred by some indigenous groups. “I think it is important to be aware of these concerns and to work with the indigenous people to make it something positive for both sides,” Brandenburg says. In 2013, the project was officially renamed the Daniel K. Inouye Solar Telescope (DKIST) to honor the late senator from Hawaii who had a strong record of support for fundamental scientific research, and astronomy in particular. Brandenburg explains that in Hawaii everyone knows DKI, almost like JFK in the rest of the country.

When it begins regular operations in 2020, DKIST will be the largest solar telescope in the world. It promises to revolutionize observations of the sun’s magnetic field, which are essential for understanding and predicting the explosive events that create space weather for our planet. The building that will house the telescope and instruments is now complete, and the team is beginning to integrate the major optical systems. The main mirror has a diameter of 4 meters (13 feet), and will generate 13 kW of power at the focus of the telescope, so heat management will be crucial. Local scientists expect DKIST to usher in a new era of solar physics. With NSO headquarters now in Boulder, and CU committed to training a new cadre of students, we can expect our city to remain a national hub for solar physics well into the future.