On February 11, 2010, NASA launched a small spacecraft towards the Sun as one of the space agency’s initial efforts to understand our host star.
And by now, nobody knows the Sun better than the Solar Dynamics Observatory. The spacecraft has been staring at the star non-stop for 10 years now, and snapping a picture of the Sun every 0.75 seconds.
Over the past decade, the observatory has captured 425 million high-resolution images of the Sun, allowing NASA to create a time-lapse of solar activity that extends across 10 years. The space agency released the video this month, and it is available for public domain.
The resulting imagery is a hypnotic 61 minute video that captures the beauty of the bright star, with each second representing a full day on Earth.
The video shows the Sun as it erupts with explosive solar activity that rises and falls throughout its 11 year cycle.
The solar cycle is measured by changes in the Sun’s activity. The Sun periodically ejects boiling-hot plasma, in the form of solar flares and solar wind, across the Solar System.
The Sun’s activity starts increasing halfway through the cycle and that means more solar flareups and outflow of radiation from our host star. However, as this solar cycle winds down, the Sun becomes less active.
However, scientists are still unsure why each solar cycle lasts approximately 11 years, or how it is generated.
There are certain moments in the hour-long video that show some significant events in the Sun’s activity. At minute 6: 20, a massive eruption flares up from the lower right side of the Sun seen as a cloud of particles that leaves the Sun’s surface and returns back down. Another massive eruption takes place at 13: 50, this time from the lower left side of the Sun.
And at 43: 20, a large group of sunspots can be seen crossing the face of the Sun over a period of two weeks. Sunspots are dark spots that mark the Sun’s surface. They are caused by the magnetic field inhibiting the transfer of energy on the surface of the Sun through the process of convection, where hot fluid rises and cooler fluid sinks.
At 12: 24, you can catch a very speedy Venus speed across the screen as it transits across the face of the Sun while Mercury transits across the Sun at 36: 18 and then makes a second appearance at 57: 38.
While the Solar Dynamics Observatory had its eyes fixated on the mesmerizing star for the past ten years, it inevitably did miss a few moments as shown by a few, very brief, dark frames. These missed moments are caused by the Earth or the Moon eclipsing the spacecraft as they transit between the Sun and the space observatory.
Meanwhile, those slight glitches when the Sun is off-center were images captured while the Solar Dynamics Observatory was calibrating its instruments.
The Sun has been around for around 4.5 billion years, and will likely stick around for another 5 billion years or so. And yet, we have barely scratched the boiling hot surface of understanding this elusive star and its explosive activity.
The Solar Dynamics Observatory will continue to keep a close eye on the Sun for years to come in the hopes of learning more about our host star.