Otkrivena planeta koja kruzi oko tri zvezde!

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Iskreno sam verovao da ovako nesto nije moguce, ali kosmos zna da iznenadi

Planet with three suns challenges astronomers

Astronomers have detected a planet with not one, but three suns, a finding that challenges astronomers' theories of planetary formation.

The planet, a gas giant slightly larger than Jupiter, orbits the main star of a triple-star system known as HD 188753 in the constellation Cygnus ("The Swan").

The stellar trio and its planet are about 149 light-years from Earth and about as close to each other as our sun is to Saturn, US scientists report in the journal Nature.

A light-year is about 10-trillion kilometres, the distance light travels in a year.

If you stood on the planet's surface, you would see three suns in sky, although its orbit centres around the main yellow star among the trio.

The larger of the other two suns would be orange and the smaller would be red, astronomers at California Institute of Technology said in a statement.

The new finding could upset existing theories that planets usually form out of gas and dust circling a single star, and could lead scientists to look in new places for planets.

"The implication is that there are more planets out there than we thought," the commentary said.

Caltech astronomer Dr Maciej Konacki, who wrote the research article, refers to the new type of planets as "Tatooine planets," because of the similarity to Luke Skywalker's view of his home planet by the same name, with its multiple suns, in the original Star Wars film.

The fact that a planet can even exist in a multiple-star system is amazing in itself, he said.

Binary and multiple stars are quite common in the solar neighbourhood, and in fact outnumber single stars by some 20 per cent.

But so far, most extrasolar planets, those discovered outside our planetary system, have been detected by watching for a characteristic wobble in the stars their orbit, reflecting the gravitation pull the planets exert on their suns.

This method is less effective for binary and multiple star systems, and existing theories said planets were unlikely to form in this kind of environment.

Dr Konacki found a new way to identify planets by measuring velocities of all bodies in a binary or multiple star system

An artists' rendering of the planet and three stars, as seen from a hypothetical moon, is available at

Dopuna: 15 Jul 2005 9:50

Jos par linkova:
http://news.yahoo.com/s/space/triplesunsetplanetdi.....MlJVRPUCUl

http://news.yahoo.com/s/nm/space_suns_dc;_ylt=AgXA.....MlJVRPUCUl

http://www.cnn.com/2005/TECH/space/07/14/planet.suns.reut/index.html

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Ne znam sta im je cudno... Ako su tri zvezde u sistemu uspostavile medjusobnu ravnotezu gravitacija, zasto se oko njih ne bi stvarale planete, jer bi onda trebalo i da je polje gravitacije te tri zvezde ravnotezno i izbalansirano... ne vidim zasto se oko njih ne bi okretale planete i kosmicka prasina i nastajanje planeta bilo kao sto je i ranije objasnjeno...

Ineresantna cinjenica anyway...

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Pa, mislim da je to neverovatan splet okolnosti...
Ne znam da li igde ima trajektorija te planete... To bi bilo interesantno

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zamislite izlazak sva tri sunca, mora da je mnogo lepo kad se potrefi da izlaze u isto vreme! ko na K-Pax-u...!

bas bi volela da letujem tamo

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Vidite da su poceli da planetu zovu Tatooine, kao rodna planeta Luke Skywalkera

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leggy, imas onu sliku malo vecu? vidim da pise da je "small"

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Ova slika koja pise ovde je sa sajta, link na nju. To je umetnicko vidjenje

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http://www.nasa.gov/vision/universe/newworlds/threesun-071305a.html

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An extrasolar planet under three suns has been discovered in the constellation Cygnus by a planetary scientist at the California Institute of Technology using the 10-meter Keck I telescope in Hawaii. The planet is slightly larger than Jupiter and, given that it has to contend with the gravitational pull of three bodies, promises to seriously challenge our current understanding of how planets are formed.

This artist's animation shows the view from a hypothetical moon in orbit around the first known planet to reside in a tight-knit triple-star system. The gas giant planet, discovered using the Keck I telescope atop Mauna Kea in Hawaii, zips around a single star that is orbited by a nearby pair of pirouetting stars. (Image credit: NASA/JPL-Caltech)

In the July 14 issue of Nature, Maciej Konacki, a senior postdoctoral scholar in planetary science at Caltech, reports on the discovery of the Jupiter-class planet orbiting the main star of the close-triple-star system known as HD 188753. The three stars are about 149 light-years from Earth and are about as close to one another as the distance between the sun and Saturn.

In other words, a viewer there would see three bright suns in the sky. In fact, the sun that the planet orbits would be a very large object in the sky indeed, given that the planet's "year" is only three and a half days long. And it would be yellow, because the main star of HD 188753 is very similar to our own sun. The larger of the other two suns would be orange, and the smaller red.

Konacki refers to the new type of planet as "Tatooine planets," because of the similarity to Luke Skywalker's view of his home planet's sky in the first Star Wars movie.

"The environment in which this planet exists is quite spectacular," says Konacki. "With three suns, the sky view must be out of this world-literally and figuratively."

However, Konacki adds that the fact that a planet can even exist in a multiple-star system is amazing in itself. Binary and multiple stars are quite common in the solar neigborhood, and in fact outnumber single stars by some 20 percent.

Researchers have found most of the extrasolar planets discovered so far by using a precision velocity technique that is easier to employ on studies of single stars. Experts generally avoided close-binary and close-multiple stars because the existing planet detection techniques fail for such complicated systems, and also because theories of solar-system formation suggested that planets were very unlikely to form in such environments.

Konacki's breakthrough was made possible by his development of a novel method that allows him to precisely measure velocities of all members of close-binary and close-multiple-star systems. He used the technique for a search for extrasolar planets in such systems with the Keck I telescope. The planet in the HD 188753 system is the first one from this survey.

"If we believe that the same basic processes lead to the formation of planets around single stars and components of multiple stellar systems, then such processes should be equally feasible, regardless of the presence of stellar companions," Konacki says. "Planets from complicated stellar systems will put our theories of planet formation to a strict test."

Scientists in 1995 discovered the first "hot Jupiter"-in other words, an extrasolar gas-giant planet with an orbital period of three to nine days. Today, more than 20 such planets are known to orbit other stars. These planets are believed to form in a disk of gas and condensed matter at or beyond three astronomical units (three times the 93-million-mile distance between the sun and Earth).

A sufficient amount of solid material exists at three astronomical units to produce a core capable of capturing enough gas to form a giant planet. After formation, these planets are believed to migrate inward to their present very close orbits.

If the parent star is orbited by a close stellar companion, then its gravitational pull can significantly truncate a protoplanetary disk around the main star. In the case of HD 188753, the two stellar companions would truncate the disk around the main star to a radius of only 1.3 astronomical units, leaving no space for a planet to form.

"How that planet formed in such a complicated setting is very puzzling. I believe there is yet much to be learned about how giant planets are formed," says Konacki.

http://www.sciencedaily.com/releases/2005/07/050715222557.htm

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A strange, distant world with three suns is baffling astronomers and challenging established theories.

The hefty planet is bigger than Jupiter although it stays very close to its main star; 20 times closer, in fact, than the Earth is to our Sun.

Some experts are puzzled because this intimate location should have stopped the body's formation.

"You shouldn't see it, but you do see it," German researcher Artie Hatzes told news@nature.com.

The planet, which is nestled within the triple star system known as HD 188753, lies 149 light-years from Earth in the Cygnus constellation.


You shouldn't see it, but you do see it
Artie Hatzes, Thuringia State Observatory
The star at the centre of the system is very much like our own Sun, and its planet whirls around it once every 3.35 days. Then, in a remote binary orbit, at about the distance from our Sun to Saturn, two more stars hug each other closely.

Strange sunsets

Sunsets on this faraway planet would be like nothing we have ever seen. "With three suns, the sky view must be out of this world," said Maciej Konacki, from the California Institute of Technology, US, who identified the planet.

However, it is not the thought of ethereal sunsets that is upsetting some scientists: it is the planet's location combined with the existence of the other two suns.

Conventional theory holds that giant planets form far away from their star, with material building up around an icy seed. According to many experts, such nuggets could never begin within the inner reaches of a blazing star.

Of course, some giant planets do ride orbits close to stars, but many astronomers speculate that these "hot Jupiters" grew in further flung places before migrating inwards.

The trouble is, this could not have happened in HD 188753, Professor Konacki believes.

The reason is the binary stars, which are whirling around in just the place - the so-called ice-line - where hot Jupiters should begin their existence. According to Professor Konacki, these two suns would smash any embryonic planets into oblivion.

Professor Hatzes thinks the most likely explanation is that the planet formed in its present location, but without the ice core. One possibility is that the core could have formed with less volatile materials, which could be solid in sweltering conditions.

In contrast, Professor Konacki thinks hot Jupiters might be failed stars, which had insufficient matter to start fusing hydrogen into helium.

However, both Hatzes and Konacki agree on one thing: more of these unusual systems will be found. "Most stars in our galaxy are in multiple systems; our own sun is in a minority," Professor Hatzes, from Thuringia State Observatory

http://news.bbc.co.uk/1/hi/sci/tech/4682361.stm