The sun is the biggest star located at the centre of the Solar System. It is a near-perfect sphere of hot plasma believed to have a diameter of roughly 864,000 miles – 109 times the size of the Earth – and reaches temperatures of roughly 15,000,000C. It also has a magnetic field that varies across the surface of the sun, causing a number of so-called “sunspots”.
It was revealed during Amazon Prime’s “Spacefiles” that NASA noticed these anomalies after analyising time-lapse photographs.
The 2004 series explains how the sheer size of the sun compares to Earth.
The narrator says: “Our own planet can fit inside the sun over a million times – it is so big, the sun comprises 99.8 percent of the Solar System.
“[It is] a ball of incandescent gas held together by gravity.
“This is the solar surface, the yellow photosphere and at 500km deep, it’s the wispy shell of gas that produces sunlight.
“Gas rises through the granules, cools, and descends again through the separating lanes.”
The programme went on to discuss the sunspots, adding that although they appear small, they are actually much larger than our planet.
It continued: “Time-lapse of the rotating sun reveals sunspots.
“They come and go over several days and just one could swallow Earth.
“They’re cooler than the surrounding photosphere whose temperature is almost 6,000C.
“The dark centre of a sunspot – the umbra – is just 4,000C and its warmer periphery, the penumbra, is 5,300C.
“This compression is caused by local magnetic fields and their intensity surpasses currents, bringing hot gasses from the convection zone below.”
Scientists have previously revealed how the sun will eventually evolve to engulf to the Earth in roughly five billion years time.
It currently sits in what is known as the main sequence, a band of stars in hydrostatic equilibrium – meaning it is resting at a constant point due to external forces such as gravity.
Louise Harra, Professor of Solar Physics at UCL Mullard Space Science Laboratory, revealed how it has been comfortably placed here for more than 4.5 billion years, but that will not last forever.
She told BBC Radio 4 listeners on a 2015 episode of “In Our Time” called “The sun” that it is “quite a boring star, really”.
Ms Harra went on to reveal how the sun could come to the end of its life.
She continued: “It’s halfway through its life now, it lays on the main sequence and that’s where 90 percent of stars are when they convert hydrogen to helium.
“But if the star is not big enough to create fusion then it does not have enough energy to create light.
“It is about 4.5 billion years old and it has about 5.5 billion to go.
“The main sequence is just the lifetime of the star – its ability to convert hydrogen to helium.”