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NuSTAR Takes Beautiful X-ray Image of Sol
New submitter swell points out a new image release from NASA, the first taken of the Sun by its Nuclear Spectroscopic Telescope Array (NuSTAR). It's the most sensitive shot ever taken in the high-energy X-ray range of the spectrum. Direct image link.
While the sun is too bright for other telescopes such as NASA's Chandra X-ray Observatory, NuSTAR can safely look at it without the risk of damaging its detectors. The sun is not as bright in the higher-energy X-rays detected by NuSTAR, a factor that depends on the temperature of the sun's atmosphere. ... With NuSTAR's high-energy views, it has the potential to capture hypothesized nanoflares -- smaller versions of the sun's giant flares that erupt with charged particles and high-energy radiation. Nanoflares, should they exist, may explain why the sun's outer atmosphere, called the corona, is sizzling hot, a mystery called the "coronal heating problem." The corona is, on average, 1.8 million degrees Fahrenheit (1 million degrees Celsius), while the surface of the sun is relatively cooler at 10,800 Fahrenheit (6,000 degrees Celsius). It is like a flame coming out of an ice cube. Nanoflares, in combination with flares, may be sources of the intense heat.
That's why our star system is the "solar" system.
Plenty of words drift or even start out meaning things much more general or abstract than their root components. Geyser used to refer to a very specific spring in Iceland, and now refers to any similar one regardless of location for example.