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The sun's sprung a leak! Enormous coronal hole that is 50-EARTHS-wide spotted on star (but don't worry, it's harmless)

Coronal holes are regions of corona where magnetic field reaches out into space rather than looping back down
They were first observed in images taken by astronauts on board NASA's Skylab space station in 1973 and 1974
Can remain visible to scientists for years, although the exact shape changes all the time

Published: 05:36 EST, 16 October 2015 | Updated: 08:14 EST, 16 October 2015

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Astronomers have spotted what looks like an enormous chasm sprawled across the sun's surface.

The phenomenon, known as a coronal hole, is 50-Earths-wide and shows up as a vast patch of black on Nasa's newly released image.

Captured by Nasa's Solar Dynamics Observatory on 15 October, the region occurs where a magnetic field fails to loop back down to the sun's surface instead sending out coronal material in what is called a high-speed solar wind stream.

Awe-inspiring: The image, take on 15 October, was taken in wavelengths of 193 Angstroms, which is invisible to the human eye

Nasa said: 'Coronal holes are magnetically open areas that are one source of high-speed solar wind.

'They appear dark when viewed in many wavelengths of extreme ultraviolet light, such as seen here. At times, the solar wind can generate aurora at higher latitudes on Earth.’

While the image may at first look alarming, it does not indicate that we are in any danger. Coronal holes are a common feature on the sun, though they appear at different places - particularly near the poles - and with more frequency at different times of the sun's activity cycle.

They are generally more common when the sun is at a less active point in its 11-year cycle.

The holes' effects are usually harmless, although in some cases satellite communications and high-altitude radio transmissions can be temporarily disrupted.

A coronal hole was also spotted at the beginning of the year (pictured). In January the phenomenon occurred closer to the south pole

They can also trigger the stunning aurora over Earth's skies - although solar flares and coronal mass ejections can also be responsible for the natural wonder.

The high-speed solar winds originating from this coronal hole triggered a geomagnetic storm near Earth that resulted in several nights of auroras earlier this month.

The hole is currently moving westwards - to the right, from Earth's perspective - so solar winds will remain strong, National Oceanic and Atmospheric Administration (NOAA) officials have said.

Coronal holes were first observed in X-ray images taken by astronauts on board Nasa's Skylab space station in 1973 and 1974.

The material that constantly flows from the sun is called the solar wind, which typically 'blows' at around 250 miles (400 km) per second.

When a coronal hole is present, however, the wind speed can double to nearly 500 miles (800 km) per second.

WATCH A SOLAR TORNADO SWIRL ACROSS THE SUN'S SURFACE

A huge ‘tornado’ has been caught on camera spinning across the surface of the sun.

Its rampage lasted 40 hours between September 1 and 3, according to Nasa’s Solar Dynamics Observatory (SDO), which watched the storm.

The tornado-like formation was described as ‘a small, but complex mass of plasma’ that gyrated and spun.Unlike those on Earth, which leave a trail of destruction, the solar tornado was simply assimilated back into the sun.

‘It was stretched and pulled back and forth by powerful magnetic forces but not ripped apart in this sequence,’ Nasa said.

The plasma is made up of ionised iron particles – those stripped from their electrons.

Nasa said they are as hot as 2.8 million degrees°C (5-million°F).

Professor Iver Cairns, a solar physicist at the University of Sydney, estimated the plume of particles may have been 43,495 miles (70,000km high) and about five times the diameter of the Earth, Fairfax media via The Sydney Morning Herald reported.

However, this is at the larger end of the spectrum for solar tornadoes.

He explained that the spiralling shape appeared near the equator and that the main cause ‘relates to the phenomenon of magnetic reconnection,’ which is when the sun’s magnetic forces are converted into motion and heat.

He said the ‘tornado’ is also partly caused by a coriolis force, which is also responsible for the formation of twisters and cyclones on Earth.

Physicists describe the coriolis effect as the deflection of air, or another moving object as a result of the Earth, or in this case the sun’s rotation.

Professor Cairns said that while plasma plumes are common on the sun’s surface, they rarely take the form of a vortex. However, others disagree.

The first example was only reported in 2010, he said.

A total of 16 solar super-tornadoes have been spotted since, but it's thought there could be 10,000 whirling across the sun's surface at any given time, Space.com reported.