Eta Carinae is a binary star system approx. 7,500 light-years away in the constellation Carina. Also known as HD 93308 and Hen 3-481, the system was first cataloged by English astronomer Edmond Halley in 1677 as a fourth-size star. In 1838, Eta Carinae underwent a catastrophic outbreak called the Great Outbreak that quickly grew to become the second brightest star in heaven in 1844 in April of that year. The star has since faded, but the new ultra-violet image from the NASA / ESA Hubble Space Telescope shows that the spectacular screen is still in progress and reveals details that have never been seen before.
Eta Carinae is one of the most massive binary systems astronomers can study in detail. The smaller star is about 30 times the sun's mass and can be as much as one million times brighter. The primary star contains about 90 solar masses and emits 5 million times the sun's energy production.
Violent mass ejections are not uncommon in the history of Eta Carinae. The system has been blighted by chaotic outbreaks, which often burst parts of themselves in space, but the great outbreak was particularly dramatic.
The resulting light radiation was omitted by Sirius, which is nearly a thousand times closer to the earth, and for a time, Eta Carinae made an important navigational star for seafarers in the South Sea. This close call stopped just to destroy Eta Carinae, and the light intensity gradually declined.
Astronomers have long known that the outer material thrown out in the 1840's eruptions has been heated by shock waves generated when it crashed into material previously dumped from the star.
DR. Nathan Smith of the Steward Observatory and colleagues who captured the new image of Eta Carinae expected to find light from magnesium coming from the complex array of filaments seen in the light of glowing nitrogen (shown in red). Instead, a whole new fluorescent magnesium structure was found in the space between the dusty bipolar bubbles and the extremely shock-heated nitrogen-rich filaments.
"We have discovered a large amount of hot gas that was triggered in the outbreak, but have not yet collided with the other material around Eta Carinae," said Dr. Smith.
"Most of the emissions are located where we expected to find an empty cavity. This extra material is fast, and it & # 39; s ante & # 39; relative to the overall energy of an already strong star beam."
The new data is important to understand how the outbreak began because it represents the rapid and energetic exhaust of material that might have been expelled by the star shortly before the expulsion of the rest of the bill.
Another striking feature of the picture is the stripes visible in the blue region outside the lower
. These stripes appear where the star's light rays protrude through the dust lumps scattered along the bubble surface.
Where the ultraviolet light strikes the dense dust, it leaves a long, thin shadow that extends across the globe the surrounding gas.
"The pattern of light and shadow is reminiscent of sunbeams as we see in our atmosphere when sunlight flows past a cloud's edge, although the physical mechanism creates Eta Carinae's onion is different," said Dr. Jon Morse from the BoldlyGo Institute.
"For decades, we had used Hubble to study Eta Carinae in visible and infrared light, and we thought we had a beautiful full account of its outcast waste. But this new ultraviolet slide looks incredibly different and reveals gas, we did not see either visible light or infrared images, "Smith said.
"We are excited about the possibility that this type of ultraviolet magnesium emission can also expose previously hidden gas to other types of objects that expel material, such as protostars or other dying stars; and only Hubble can take these kinds of images." 19659019]