This is active region 2177. Any guesses what that is? Hint: It's on the Earth & Space subsite for a reason.
Your instinct might be to guess something microscopic in size – but the subject of this photograph is actually quite large.
All photos featured by kind permission of Alan Friedman
The answer? You're looking at a photo of the Sun – a closeup of active region 2177, to be exact, captured in October 2014. "The photo is a processing that I made from data collected at the Big Bear Solar Observatory's 1.6-meter New Solar Telescope," photographer Alan Friedman tells io9. This particular region of the solar chromosphere (the second of three main layers in the Sun's atmosphere) happens to resemble a microscopic mineral accumulation, or a budding flower:
According to NASA APOD:
The petals dominating the frame are actually magnetically confined tubes of hot plasma called fibrils, some of which extend longer than the diameter of the Earth. In the central region many of these fibrils are seen end-on, while the surrounding regions are typically populated with curved fibrils. When seen over the Sun's edge, these huge plasma tubes are called spicules, and when they occur in passive regions they are termed mottles.
Friedman acquired this image with a filter that allows light from hydrogen to pass through, after which, the resulting black and white image was inverted and colorized. The original image data recorded by the 1.6 meter New Solar Telescope can be seen on Friedman's website. See also Big Bear Solar Observatory's gallery of images.