A NASA spacecraft perched in Earth’s orbit has been monitoring the sun for the past decade. That’s a year before a full solar cycle – the time it takes for the sun’s north and south poles to rotate.
Between June 2, 2010 and June 1, 2020, NASA’s Solar Dynamics Observatory captured 425 million high-resolution images of our star. That’s about a snapshot every 0.75 seconds, on average. The team recently compiled some of the images into a fascinating hour-long video of the moving sun.
Every second in the video represents a day in the life of the sun.
The time lapse makes the sun look like a spinning disco ball – bright in some places, gloomy in others.
That’s because its hot gases constantly move. During an 11-year solar cycle, the sun’s magnetic fields can tangle and stretch. This creates sunspots – darker, cooler spots on the sun’s surface that form when the magnetic fields are particularly strong.
In October 2014, NASA recorded the largest sunspot in nearly a quarter century, a patch the size of Jupiter. The sunspot triggered multiple explosions known as sun flares, appearing as bright flashes in the video. That same month, the light and dark patterns on the sun’s surface bore a striking resemblance to a Jack-o-Lantern just in time for Halloween.
The sun’s magnetic energy peaked, known as the solar maximum, in 2014. During that time, the explosions and eruptions on the sun’s surface were so violent that they could be seen as light from Earth’s surface. Solar maxima can also cause power outages and electricity shortages.
The sun’s magnetic activity has declined since then, but NASA observers still managed to capture some notable events, such as Mercury passing in front of the sun in November 2019. That event won’t happen again until 2032.
However, some snapshots are missing. The video is dotted with the occasional dark frame, when Earth or the moon passed between the sun and NASA’s Solar Dynamics Observatory. In 2016, a technical issue also caused the camera to go offline for about a week.
But for the most part, the video represents all of the sun’s growing and waning activity over the past decade.
Scientists now speculate on whether the sun may have entered its next solar cycle. NASA observers captured a different solar flare on May 29, the largest since October 2017. That could be a sign that the sun’s activity has started to pick up again, but it may take another six months or a year to be safe.
Meanwhile, NASA will have it on camera.
