ucar Highlights 2007
|
|
|
|
|
|
A magnetic team: Peering into the Sun’s plasmaMore than a decade of international collaboration paid off in 2006 with the launch of a new satellite-borne imager now gathering the richest data ever collected on magnetism across the Sun’s highly charged surface. Japan’s Hinode mission includes contributions from the United States and Europe. “We combined scientists, technologies, funding agencies, and cultures to build Hinode,” says Saku Tsuneta (Japan’s National Optical Observatory). When Japanese scientists began discussing Hinode in the mid-1990s, Bruce Lites, of NCAR’s High Altitude Observatory, was invited to participate. Lites and colleagues had already designed the Advanced Stokes Polarimeter, based at the National Solar Observatory since 1991. The ASP and its successors provided critical glimpses of solar magnetism, but they were limited by atmospheric conditions and the length of the day itself. Scientists hungered for a fuller picture of how magnetism is channeled across the Sun’s surface from hour to hour, day to day, and month to month.“You really need long time sequences to follow the evolution of the magnetic fields responsible for heating the upper layers of the solar atmosphere and for the variables that affect our climate,” explains Lites.
With NASA support, Lockheed Martin built a focal plane package for Hinode’s Solar Optical Telescope that included a spectropolarimeter. Drawing on their pathbreaking work with ASP, Lites and NCAR engineers David Elmore and Kim Streander collaborated with Lockheed principal investigators Alan Title and Theodore Tarbell, NASA program manager Lawrence Hill, and others. To help analyze the data, Lites assembled a team of graduate and postdoctoral researchers from the Netherlands, Spain, and Japan: Alfred de Wijn, Rebecca Elliott, and Masuhito Kubo (below, left to right). According to Title, “Hinode images are revealing irrefutable evidence for the presence of turbulence-driving processes that are bringing magnetic fields, on all scales, to the Sun’s surface.” One surprise is the liveliness of the fields, not only in and near sunspots but across quiet regions as well, says Lites. The new data may compel physicists to revise their understanding of how the Sun’s uppermost atmosphere is heated from below.
Filling in the gaps | Tiny troubles in the air | Coding the atmosphere | A magnetic team |Layering the atmosphere | A window on water vapor | A research aircraft is born |
Hinode
Highlights - NCAR's High Altitude Observatory (Earth & Sun Systems
Lab)
