Why can't Brown Dwarf die

Turn on in space - cosmic failure charms stellar companion

Brown dwarfs: News from these enigmatic, actually not at all brown-looking birds of paradise

In 1963, Dr. Shrinivas Kulkarni for the first time about the missing link between star and planet. In 1975, Jill C. Carter gave them a name. And in 1995 the first of them was found around the star Gliese 229. Brown dwarfs are now part of the cosmic inventory. They are star-like celestial bodies that have not made the leap into stellar independence: they do not fuse hydrogen to helium. Still, some of them are arguably "fiery" in a certain way, at least in terms of their temperament, but less so in terms of their temperature. Now a brown dwarf has been caught red-handed while attempting to approach. (See photo of a brown dwarf with new technology) The beloved is a sun-like star in its prime, strutting only 58 light-years from Earth. How the brown dwarf managed to get there is completely a mystery to astronomers.

Evil astronomer tongues claim that Brown Dwarfs, i.e. the well-known, but still not entirely sure, but fabulous-sounding astral mythical creatures from the depths of space, are nothing more than cosmic failures, misfires in space, stellar good-for-nothing and would-be - Stars that have too little "juice" to ignite. Well, the generally accepted and current theory of Brown Dwarfs does not, in fact, speak in favor of a pronounced astral "potency" of these objects. Because these pseudostellar duds do not have enough mass to ignite the nuclear combustion processes inside them. It may be of little consolation for them that, on the other hand, they are significantly more massive than planets. Somehow these cross-border commuters move in no man's land as far as their classification is concerned, so that sometimes the scholars do not automatically agree with every candidate whether he can advance to a brown dwarf or just receive the status of a planet.

No nuclear fusion in brown dwarfs

Be that as it may, brown dwarfs are definitely a case of their own. They are formed like stars by collapsing gas clouds. Nevertheless, they do not succeed in reaching the mass that would be necessary to reach the central maximum temperature inside them, which the nuclear fire ignites. Because the mass of brown dwarfs usually barely exceeds the eight percent mark of our own sun. Normal stars, on the other hand, on which hydrogen is burned to form helium, owe their existence to such a chain reaction. However, no nuclear fusion takes place on brown dwarfs.

A brown dwarf condenses due to its gravitation; the gravitational energy is converted into heat energy, which is why it shines weaker at the beginning of its life. It cools down slowly, fades noticeably and then turns into a black dwarf. Many astronomers, who assume that these celestial bodies represent a link between stars and planets, firmly believe that one can learn a lot about the formation of stars and planets through these structures.

Even though these bizarre, star-like beings did not lose or experience enough mass when they were formed to set the nuclear fusion process in motion that makes our sun "shine", they "shine" in their inimitable way by convert their gravitational energy (while they gradually shrink) into radiation. But what is even more interesting is that they even emit X-rays. Already in the middle of the year before last, the NASA X-ray telescope Chandra suddenly registered a bright flash in the X-ray range: the brown dwarf flickered quite unexpectedly and sent out X-rays. Even regular weather processes in the form of radio storms (see Surprising Discovery in Space) are said to have occurred on it.

The next surprise: The amount of energy released was many times higher than that which the most energetic eruptions of our sun can release. During the following series of observations, the scientists also found that the magnetic field of the target objects was extremely weak, which was astonishing because research had previously assumed that the release of such emissions was generated by the energy of a strong magnetic field. But that's not all: Recently, an international team of astronomers tracked down 30 such pseudostellar duds in one fell swoop under the direction of the Swedish researcher Lennart Nordh from the University of Stockholm in the Rho Ophiuchi gas cloud, which is only 540 light years away.

And now there is again something new to report about these enigmatic cosmic, actually not at all brown-looking birds of paradise, which are slightly reddish in optical light, but decidedly more clearly recognizable in infrared light.

Only 14 astronomical units away from the central star

What not exactly many astronomers had assumed, indeed what only very few of them had expected, seems to have been the norm for millions of years, 58 light-years away from our home planet. As long as the telescopes of the Gemini Nord-www.gemini.edu and the Keck Observatory do not have a kink in their optics, a star in our immediate vicinity will actually be charmed by a brown dwarf.

It is a brown dwarf that has a mass far exceeding that of all the planets in our solar system combined,

clarifies Michael Liu from the Department of Astronomy at the University of Hawaii. It may be that the exosolar toddler has about 55 to 78 times the mass of the gas giant Jupiter and is constantly orbiting the star 15 Sagittae (Sge, also known as HR 7672. What is remarkable, however, is the fact that the brown dwarf has the sun-like 15 Sge, which at 3 billion years is "a few" years younger than our sun, bewitched at a remarkably small distance. There are just 14 astronomical units that separate it from the central star, which, transferred to our planetary system, would correspond to the distance between the sun and Uranus the newly discovered brown dwarf is likely to be one of the densest substellar objects that have ever been observed directly around a normal star.

"The discovery suggests that there seem to be brown dwarfs around sun-like stars that are no further away from their main star than the outer planets in our solar system are from the sun," said Michael Liu. "The companion of 15 Sge is probably too massive to have formed like a planet. So it was not born from a disk of dust that orbited the emerging sun. But that means that there are a multitude of processes that cause this Determine the appearance of other solar systems. "

The first indications of a companion around 15 Sge are already ten years old when the search for planets near the distant sun was carried out. These first signs of a massive companion then led to new detailed observations in the summer of last year at the Gemini Nord telescope and in November and December 2001 at the Keck telescope.

The find poses new challenges for astronomers: "Now that we know that brown dwarfs can exist in this region of a system, we naturally want to find out how often this occurs. This could give us important clues about the development of planetary systems around sun-like stars . "

The fact that brown dwarfs even exist in space was, strictly speaking, highly controversial until five years ago. Only since then Dr. Shrinivas Kulkarni from the California Institute of Technology and his team were able to confirm the existence of these cool and faintly glowing objects, found these structures, which got their fairytale name from the well-known SETI researcher Dr. Jill Tarter owe general acceptance in science.

What remains is the certain knowledge that brown dwarfs also have their hardships and hardships when looking for a partner. Neither real planets nor robust stars can do anything with these hybrid beings. This will continue to be the case in the future, as it has long been known that stars that combine to form a double or polygamous multiple star system are generally quite picky. Somehow brown dwarfs are pitiful astral creatures. (Harald fence)

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