Since the dawn of our existence, we have witnessed the Sun rising above the horizon, bathing
the Earth in its light and warmth.
We know precisely what it looks like as it passes through the blue sky above, we even
know what it looks like from the position of other planets within the solar system,
but what does it look like up close?
What do we see when we peer at the surface of the Sun?
As the only star we can observe in detail, the Sun provides a basis for our understanding
of other stars, and the better we understand other stars, the more we know about the Milky
Way.
In recent years, NASA has succeeded in touching our closest stellar neighbour, when its Parker
solar probe flew through its hostile atmosphere and captured this incredible time-lapse footage.
The footage was taken during the probes closest approach, revealing streaks of electrically
charged gas and plasma called coronal streamers zooming out into space.
A small example of how bizarre the Sun becomes the closer you get.
But we do not necessarily have to travel to the Sun to study it.
For decades astronomers have used multiple tools, including ground-based telescopes and
Earth-orbiting spacecraft to examine its mysterious, scorching layers.
The Sun is a giant sphere of unimaginably hot plasma.
It has no solid mass, meaning it doesn't have a distinct, solid surface like the Earth.
Instead, it is composed of layers made up almost entirely of hydrogen and helium, and
so the surface of the Sun is considered the first visible layer.
The light that bathes the Earth during the day originated deep within the core of the
Sun and is created during a process called nuclear fusion.
Light is made of particles called photons, which bounce around within its interior, gradually
working their way outwards, while colliding over and over again with atoms.
After tens of thousands of years, photons will reach a level where the plasma is less
dense, allowing them to escape into space, and it is this level that is commonly referred
to as the surface of the Sun, a layer called the photosphere.
Although we call it the surface, the photosphere is actually the first layer of the solar atmosphere.
It is the deepest layer that we can directly observe.
It is about 400 kilometres thick, which is 250 miles thick, making it relatively thin
considering the overall size of the Sun, which accounts for 99.86% of all the mass in the
solar system.
It reaches scorching temperatures of above 5,500 degrees Celsius, which is 10,000 degrees
Fahrenheit.
Making it hot enough to melt diamond.
This magnificent footage is of the Sun's surface, revealing in unprecedented detail dynamic
cell-like structures moving and evolving in shape and size.
What you are viewing is the last layer of the Sun before light escapes into space.
At this point, photons are already thousands of years old, before being released in all
directions, some of which, make the 8 minute and 20-second journey to Earth.
The footage was captured using the Daniel K.Inouye solar telescope and is currently
the highest resolution images of the photosphere taken so far, revealing details as small as
18 miles or 30 kilometres.
The reason the photosphere seems like it's bubbling is because hot plasma from within
the Sun rises to the surface, cools and sinks back down in a process called convection.
The same process can be seen when water is bubbling in a boiling pot, for example.
Hot, new rising plasma is visible in the bright regions, while the dark edges is where it
cools and sinks back into the Suns interior, and each cell is estimated to be around the
size of Texas, USA.
Sparsely scattered across the photosphere are, also enormous dark features called sunspots.
These planet-sized regions appear dark because they are much cooler than their surroundings,
roughly 2 or 3 thousand degrees cooler in fact.
Sunspots are caused by disturbances in the Sun's powerful magnetic fields, which are
so strong they keep some of the heat from escaping and reaching the surface.
The magnetic fields are very active, often tangling, crossing and reorganising, while
frequently causing sudden, powerful explosions of energy called solar flares.
Sometimes the flares are also accompanied by coronal mass ejections, which are huge
bubbles containing billions of tons of charged particles, blasting out into space at extremely
high speeds.
These massive bursts of energy are spectacular to observe, as this footage reveals.
They are, after all, the solar systems largest, most explosive events.
Although we see the Sun every day shining in the blue skies above, it is only relatively
recently that we have had the technology and know-how to peer past its powerful glare and
study its bizarre bubbling surface.
By better understanding the photosphere and monitoring the magnetic fields, astronomers
can predict when potentially dangerous solar storms will occur, which can disrupt satellites
and power grids on Earth.
Not only that, but they can also test theories about the Sun and attempt to answer some of
its biggest mysteries.