Brighter than a shimmering ghost, faster than the flick of a black cat’s tail, the Sun cast a spell in our direction, just in time for Halloween. This imagery captured by NASA’s Solar Dynamics Observatory covers a busy few days of activity between Oct. 25-28 that ended with a significant solar flare.
From late afternoon Oct. 25 through mid-morning Oct. 26, an active region on the left limb of the Sun flickered with a series of small flares and petal-like eruptions of solar material.
Meanwhile, the Sun was sporting more active regions at its lower center, directly facing Earth. On Oct. 28, the biggest of these released a significant flare, which peaked at 11:35 a.m. EDT.
Music: "Immersion" from Above and Below. Written and produced by Lars Leonhard
The Sun emitted a significant solar flare peaking at 11:35 a.m. EDT on Oct. 28, 2021. NASA’s Solar Dynamics Observatory, which watches the Sun constantly, captured an image of the event.
Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth’s atmosphere to physically affect humans on the ground, however — when intense enough — they can disturb the atmosphere in the layer where GPS and communications signals travel.
To see how such space weather may affect Earth, please visit NOAA's Space Weather Prediction Center http://spaceweather.gov/, the U.S. government’s official source for space weather forecasts, watches, warnings, and alerts. NASA works as the research arm of the nation’s space weather effort. NASA observes the Sun and our space environment constantly with a fleet of spacecraft that study everything from the Sun’s activity to the solar atmosphere, and to the particles and magnetic fields in the space surrounding Earth.
This flare is classified as an X1.0-class flare.
X-class denotes the most intense flares, while the number provides more information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, etc. Flares that are classified X10 or stronger are considered unusually intense.
Earlier in the week, from late-afternoon on October 25th through mid-morning on the 26th, a different active region on the Sun gave a show of small flares and eruptions of plasma.
An X1.0 class solar flare flashes in center of the Sun on Oct. 28, 2021. This image was captured by NASA's Solar Dynamics Observatory and shows a blend of light from the 171 and 304 angstrom wavelengths.
NASA's Solar Dynamics Observatory captured this image of a solar flare — as seen in the bright flash at the Sun’s lower center — on Oct. 28, 2021. The image shows a subset of extreme ultraviolet light that highlights the extremely hot material in flares and which is colorized here in teal.
Footage of the October 25-26th activity captured by the Solar Dynamics Observatory in extreme ultraviolet light (171 angstrom wavelength). The footage is rotated to show more of the activity in a widescreen format.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 126.96.36.199.0