The last time you heard the term "gradient filter," it was probably in reference to a feature on a photo editing program, but scientists studying images and video collected by NASA's Solar Dynamics Observatory use gradient filters, too — often with absolutely mesmerizing results.
In this just-released video, dubbed "Gradient Sun" by the talented folks at NASA's Scientific Visualization Studio, the Agency highlights how "a particularly beautiful movie of the sun" can blur the line separating science from art. Here, researchers use a gradient filter to study coronal loops — beautiful, arcing bands of solar material, generated and contained by magnetic flux within the Sun's body. Says NASA:
Scientists... use gradient filters to enhance contrast, using them to accentuate fine structures that might otherwise be lost in the background noise. On the sun, for example, scientists wish to study a phenomenon known as coronal loops, which are giant arcs of solar material constrained to travel along that particular path by the magnetic fields in the sun's atmosphere. Observations of the loops, which can be more or less tangled and complex during different phases of the sun's 11-year activity cycle, can help researchers understand what's happening with the sun's complex magnetic fields, fields that can also power great eruptions on the sun such as solar flares or coronal mass ejections.
Absolutely beautiful. You'll want to watch this in HD, obviously, with headphones if you have them. [Goddard Multimedia]