Space

Unraveling The Stunning Invisible Details In The Sun

Elaine Hannah
First Posted: Jan 19, 2017 03:30 AM EST

The Atacama Large Millimeter Array (ALMA) has captured images of invisible details of the Sun. These include the dark, contorted center of an evolving sunspot that is about twice the diameter of planet Earth.

Tim Bastian, an astronomer with the National Radio Astronomy Observatory in Charlottesville, VA, said that they are accustomed to seeing how the Sun appears in visible light, but that can only tell so much about the dynamic surface and energetic atmosphere of the nearest star. He further said that to fully understand the Sun, they need to study it across the entire electromagnetic spectrum. This includes the millimeter and submillimeter portion that ALMA can observe.

ALMA has captured the millimeter-wavelength light emitted by the Sun's chromosphere, which is the region that lies just above the photosphere that forms the visible surface of the Sun. The astronomers tracked the massive sunspot at wavelengths of 1.25 millimeters and 3 millimeters using the two of ALMA's receiver bands. They found in the images the differences in temperature between parts of the Sun's chromosphere, according to Science Daily.

Sunspots are passing spectacles on the photosphere of the Sun. They are the dark spots that develop on the surface of the Sun caused by concentrations of the magnetic field flux. These could lead to solar flares that blast the Sun's material out into space that could trigger telecommunication problems on Earth. They appear in pairs of opposite magnetic polarity, and their number varies according to the approximately 11-year solar cycle.

The images taken by ALMA could aid the astronomers in understanding why the two levels of the chromosphere are different temperatures and how can these influence the shaping of sunspots, in which a phenomenon that is not fully understood. The European Space Organization (ESO) stated that understanding the heating and dynamics of the chromosphere is a key area of research that will be addressed in the future using ALMA.

See Now: NASA's Juno Spacecraft's Rendezvous With Jupiter's Mammoth Cyclone

More on SCIENCEwr