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The amazing moment when a star whips through the gaseous emissions of its companion and carves out a 'tunnel' have been revealed in amazing 3D models.

Eta Carinae is the most luminous and massive stellar system within 10,000 light-years of Earth, but the interaction of its two stars has been poorly understood.

Now astronomers have been able to take a closer look at what is happening in this fascinating system as gas races away at a million mph (1.6 million km/h). 

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Scientists at the American Astronomical Society in Seattle revealed their new findings for the Eta Carinae system (illustration shown). Located 7,500 light-years from Earth it consists of two starts in orbit. One is three times the size of the other and they pass every 5.5 years

The latest work by researchers at Nasa's Goddard Space Flight Center in Maryland was presented at the American Astronomical Soceity's (AAS) 225th meeting in Seattle this week. 

Known for its surprising behaviour, Eta Carinae is a system of two stars that erupted twice in the 19th century - for reasons not understood. 

Eta Carinae is located about 7,500 light-years from Earth in the constellation of Carina. The system is surrounded by the vast Homunculus Nebula, which gives it its odd shape.

Its two massive stars are in eccentric orbits, which brings them unusually close every 5.5 years - to roughly the distance between Mars and the sun.

When this happens, it appears that the smaller star carves out a path in the gas emissions of the larger star. 

The point of closest approach also co-incides with a drop of X-rays in the stars.

X-rays are produced when their winds come into contact head-on in space, being heated to millions of degrees.

But these drop during closest approach, perhaps because the smaller star is within the envelope of the larger one.

And it also appears structural changes are taking place in the system each time they pass one another. 

NASA release an unparalleled look into superstar Eta Carinae

Known for its surprising behaviour, Eta Carinae is a system of two stars (illustration shown). Ever 5.5 years they reach their point of closest approach, 140 million miles (225 million kilometres) from each other, which is roughly the average distance from Mars to the sun in our own solar system

Both produce powerful gaseous outflows called stellar winds, which enshroud the stars and hamper efforts to directly measure their properties.

Astronomers have established that the brighter, cooler primary star has about 90 times the mass of the sun and outshines it by 5 million times.

While the properties of its smaller, hotter companion are more contested, the researchers think the star has about 30 solar masses and emits a million times the sun's light.

At closest approach, known as periastron, the stars are 140 million miles (225 million kilometers) apart. The last time this occurred was in August 2014.

In the months either side of periastron, astronomers have noticed dramatic changes in the system.

These include X-ray flares and 'a play of light and shadow' as the smaller star swings around the larger one.

Over the last 11 years, the scientists have been observing the system in detail with a variety of ground-based telescopes and Nasa satellites.

This gif reveals a 3D model of the stars in orbit. The large red area is the gas emission by the larger star, and the blue area is that of the smaller star. As the smaller star whips around the larger one at closest approach, seen towards the end of the animation, it appears to carve a 'tunnel' through its companion's gas 

The point of closest approach is normally accompanied by a drop in X-rays, which is seen here in data from observations of the stellar system. This may be due to the smaller star becoming enveloped in the gaseous emissions of the larger one - and it is often accompanied by structural changes in the system

'We used past observations to construct a computer simulation, which helped us predict what we would see during the next cycle, and then we feed new observations back into the model to further refine it,' said Thomas Madura, a Nasa Postdoctoral Program Fellow at Goddard and a theorist on the Eta Carinae team.

According to this model, the interaction of the two stellar winds accounts for many of the periodic changes observed in the system.

The winds from each star have markedly different properties: thick and slow for the primary, lean and fast for the hotter companion.

The primary's wind blows at nearly one million mph (1.6 million km/h) and is especially dense, carrying away the equivalent mass of our sun every thousand years.

By contrast, the companion's wind carries off about 100 times less material than the primary's, but it races outward as much as six times faster.

As the stars spiral around each other, the smaller one carves out a spiral cavity in the outflow of the larger one. 

Both of the massive stars of Eta Carinae may one day end their lives in supernova explosions.

For now, the researchers say, there is no evidence to suggest an imminent demise of either star.

They are exploring the rich dataset from the 2014 periastron passage to make new predictions, which will be tested when the stars again race together in February 2020.