Superflare
Since superflares can occur on stars apparently equivalent in every way to the Sun, it is natural to ask if they can occur on the Sun itself. An estimate based on the original Kepler photometric studies suggested a frequency on solar-type stars (early G-type and rotation period more than 10 days) of once every 800 years for an energy of 10 erg and every 5000 years at 10 erg. One-minute sampling provided statistics for less energetic flares and gave a frequency of one flare of energy 10 erg every 5–600 years for a star rotating as slowly as the Sun; this would be rated as X100 on the solar flare scale. This is based on a straightforward comparison of the number of stars studied with the number of flares observed. An extrapolation of the empirical statistics for solar flares to an energy of 10 erg suggests a frequency of one in 10,000 years.
Solar flare
Since the beginning of space exploration, telescopes have been sent to space, where they work at wavelengths shorter than UV, which are completely absorbed by the atmosphere, and where flares may be very bright. Since the 1970s, the GOES series of satellites observe the Sun in "soft" X-rays, and their observations became the "standard measure" of flares, diminishing the importance of the Hα classification. "Hard" X-rays were observed by many different instruments, the most important today being the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). Nonetheless, UV observations are today the "stars" of solar imaging with their incredible fine details that reveal the complexity of the solar corona. Spacecraft may also bring radio detectors at extremely long wavelengths (as long as a few kilometers) that cannot propagate through the ionosphere.
The following spacecraft missions have flares as their main observation target.