First Planet Found Beyond Our Galaxy

The videos of this planetary visitor from the Helmi Stream are amazing - http://www.frequency.com/video/planet-from/556571?embed=true

http://www.huffingtonpost.com/2010/11/18/new-planet-hip-13044b_n_785690.html

The Huffington Post

New Planet HIP 13044b Is First Spotted Outside Our Galaxy

The Huffington Post | Catharine Smith First Posted: 11-18-10 06:17 PM | Updated: 11-18-10 06:17 PM

A team of researchers has discovered a Jupiter-like planet located on the outskirts of our Milky Way galaxy. It is the first of its kind to be discovered, as it is believed that the planet (called HIP 13044b) and its parent star (HIP 13044) formed outside of our galaxy and were "captured" by the Milky Way some six billion years ago, Space.com reports.

"The discovery is the first proof astronomers have that planet formation can indeed take place in other galaxies," writes National Geographic.

Scientists at the European Southern Observatory's La Silla Observatory in Chile first observed the planet, which is now located 2,000 light-years from Earth in the constellation Fornax.

Johny Setiawan, the team's head researcher told Space.com that the discovery of HIP 13044b was a surprise. "I was not expecting it in the beginning," Setiawan said. According to National Geographic, "Setiawan and his team inferred the planet's existence based on the way the gas giant gravitationally tugs on its parent star, causing the starlight to wobble slightly."

HIP 13044b's composition may be radically different from that of other planets scientists have discovered within the Milky Way. National Geographic explains:

Based on current theories for planet formation [...] astronomers say HIP 13044b shouldn't have been born in the first place: The planet's parent star is extremely metal poor, meaning it contains very few elements heavier than hydrogen and helium.

Astronomers think stars and their planets are made from the same initial building blocks, so if a star has few metals, the disk of material that surrounded the star when it was young--and from which its planets are born--was also metal-poor.

Even though gas giants are made of mostly hydrogen and helium, astronomers think the planets still require an initial core of heavy elements to attract lighter gases and grow.

The planet may be entirely gaseous, suggested Rainer Klement, who co-authored a paper with Setiawan about HIP 13044b.

But, Space.com notes, HIP 13044b is in danger. The aging parent star expanded considerably as it entered its red giant phase and will only continue growing. HIP 13044b's orbit is being pulled tighter and tighter by the mighty star; eventually, it seems the planet will be destroyed.

http://www.msnbc.msn.com/id/40258491/ns/technology_and_science-space

Cosmic 'cannibalism' brings new planet to Milky Way
Alien interloper could hint at our solar system's fate, astronomers say

By Mike Wall Senior writer
Space.com
updated 11/18/2010 3:54:28 PM ET 2010-11-18T20:54:28

Astronomers have confirmed the first discovery of an alien planet in our Milky Way that came from another galaxy.

The Jupiterlike planet orbits a star that was born in another galaxy and later captured by our own Milky Way, sometime between 6 billion and 9 billion years ago, researchers said Thursday. A side effect of the galactic cannibalism brought a faraway planet within astronomers' reach for the first time ever.

"This is very exciting," said study co-author Rainer Klement, an astronomer at Germany's Max-Planck-Institut fur Astronomie, or MPIA. "We have no ability to directly observe stars in foreign galaxies for planets and confirm them."

Stars currently residing in other galaxies are simply too far away, Klement added.

The find may also force astronomers to rethink their ideas about planet formation and survival, researchers said, since it's the first planet ever discovered to be circling a star that is both very old and extremely metal-poor. Metal-poor stars are lacking in typically lack elements heavier than hydrogen and helium.

The newfound planet, called HIP 13044b, survived through its star's red-giant phase, which our own sun will enter in about 5 billion years. So studying it could offer clues about the fate of our solar system as well, researchers said.

HIP 13044b sits extremely close to its parent star, which has now contracted again. The planet completes an orbit every 16.2 days, and it comes within about 5 million miles (8 million kilometers) of its parent star at closest approach — just 5.5 percent of the distance between Earth and the sun.

Searching for telltale tugs
The newly discovered alien planet is at least 25 percent more massive than Jupiter, researchers said. It orbits the star HIP 13044 about 2,000 light-years from Earth in the constellation Fornax.

HIP 13044 is about as massive as the sun, and it is nearing the end of its life. The star has already gone through its red giant phase — when sunlike stars bloat enormously after exhausting the hydrogen fuel in their cores.

The star is also composed almost entirely of hydrogen and helium. It is less than only 1 percent as metal-rich as our sun, making it the most metal-poor star known to host a planet, researchers said.

The research team scrutinized HIP 13044's movement using a telescope at the European Southern Observatory's La Silla Observatory in Chile. After six months of observing, they detected tiny movements that betrayed the gravitational tug of an orbiting planet.

"For me, it was a big surprise," said study lead author Johny Setiawan, also of MPIA. "I was not expecting it in the beginning."

Setiawan, Klement and their colleagues reported their results in a paper published online Thursday by the journal Science.

An extragalactic origin
Last year, another research team announced that it may have detected a planet in the Andromeda Galaxy. However, that faraway find will be nearly impossible to confirm.

The astronomers performing that previous study used a method called gravitational microlensing, which only works when a planet-hosting star happens to line up with another star. Such events happen very rarely.

HIP 13044, on the other hand, belongs to the Helmi stream of stars that were once part of a nearby dwarf galaxy. Astronomers believe our own Milky Way gobbled up the Helmi stream between 6 billion and 9 billion years ago.

While it's technically possible that the planet was born in the Milky Way and then stripped from its parent star by the interloping HIP 13044, the odds of that happening are minuscule, researchers said.

So HIP 13044 almost certainly has an extragalactic origin.

"We can be pretty sure about that," Klement told Space.com. "Stellar encounters in the Milky Way essentially don't occur. The chance that the star captured the planet from another star by an encounter is very, very unlikely."

Rethinking theories of planet formation
Most of the nearly 500 alien planets discovered so far orbit metal-rich stars, researchers said. And a metal-rich star is fundamental to the dominant theory explaining how giant planets form — the core-accretion model.

This model posits that dust and gas particles circling a young star cling together and gradually become larger, forming rocks, boulders and eventually the stony cores of giant, gassy planets like HIP 13044b.

Because its parent star is so metal-poor, HIP 13044b may have formed in a different way, researchers said. The planet may have arisen via the gravitational attraction between gas molecules, through a process termed the disk-instability model. So it may not have a rocky core at all.

"You are able to form pure gas planets by this method," Klement said.

The fact that such a metal-poor star can host planets should inspire astronomers to look at other stars like it, Klement added. Astronomers haven't examined many up to this point, so they don't have a good handle on how frequently planets might pop up around low-metal stars.

The discovery also hints that planets may have studded the cosmos from the universe's early days — back when pretty much all stars were metal-poor.

"You can think of the very first stars in the universe, or the second or third generation of stars," Klement said. "Could they already have been able to form planets? That's a very fascinating question."

Vision of our solar system's fate?
Our own sun is on the same stellar-evolution track as HIP 13044; scientists predict it will bloat into a red giant in 5 billion years or so. So astronomers may be able to learn something about the fate of our solar system by studying HIP 10344b and its parent star, researchers said.

That fate would not be pretty for Earth. HIP 13044b likely once orbited much farther away from its star but spiraled closer and closer during the red giant phase due to friction with the swollen star's envelope, researchers said. Any more interior planets would have been destroyed during this process.

When our own sun enters its red giant phase, Earth will likely get cooked.

"The inner planets, including Earth, maybe will not survive," Setiawan told SPACE.com. "But Jupiter, Saturn and the outer planets might move to closer-in orbits, exactly like we detected."

HIP 13044b is a survivor, but it won't live forever. Its parent star is due to expand again in the next phase of its stellar evolution, researchers said, and this time the planet will almost certainly be engulfed.

http://news.nationalgeographic.com/news/2010/11/101118-science-space-new-planet-...

New Planet Discovered: First Spotted Outside Our Galaxy

Ker Than

for National Geographic News

Published November 18, 2010

A new planet discovered orbiting a bloated red star is the first world we know of that was born in another galaxy.

Since the mid-1990s astronomers have been adding to the list of known exoplanets, planets that exist outside our solar system. The nearly 500 exoplanets found so far all formed in our home galaxy, the Milky Way.

But the newest member of the exoplanet club, dubbed HIP 13044b, was found in a stream of vagrant stars that loop around the Milky Way. Astronomers think this stellar stream is all that remains of a dwarf galaxy that once orbited the Milky Way.

About six billion years ago the Milky Way collided with and mostly absorbed this unnamed galaxy, leaving a trail of stars that now zips around our galaxy at more than 600,000 miles (965,600 kilometers) an hour.

The newfound planet "likely formed when the star was not yet a part of the Milky Way. It's traveled with the star all this time," said study leader Johny Setiawan, an astronomer at the Max-Planck Institute for Astronomy in Germany.

The discovery is the first proof astronomers have that planet formation can indeed take place in other galaxies, added Oskar von der Lühe, an astronomer at the Kiepenheuer-Institut für Sonnen-physik in Germany who was not involved in the study.

"It also demonstrates that planet formation takes place in galaxies of a different class than the Milky Way," von der Lühe wrote in an email. "These galaxies have a quite different pattern of evolution and star-formation history."

Gassy Planet Survived Star's Expansion

The new, extragalactic planet—described in this week's issue of the journal Science—is a gas giant with a mass of at least 1.25 times that of Jupiter, orbiting a star about 2,000 light-years from Earth.

The huge planet is too far away to be observed directly. But using a telescope at the European Southern Observatory's La Silla Observatory in Chile, Setiawan and his team inferred the planet's existence based on the way the gas giant gravitationally tugs on its parent star, causing the starlight to wobble slightly.

The team also studied HIP 13044b's parent star, which used to be like our sun. At about eight billion years old, the star is now in the red giant stage, a late phase of stellar evolution in sunlike stars.

Red giants can puff up to several hundred times their original size, and it's thought planets orbiting near these bloated stars generally get engulfed and vaporized.

Some astronomers predict Earth will experience this fate in about five billion years—but HIP 13044b somehow managed to skirt destruction.

New Planet a Big Anomaly

Based on current theories for planet formation, however, astronomers say HIP 13044b shouldn't have been born in the first place: The planet's parent star is extremely metal poor, meaning it contains very few elements heavier than hydrogen and helium.

Astronomers think stars and their planets are made from the same initial building blocks, so if a star has few metals, the disk of material that surrounded the star when it was young—and from which its planets are born—was also metal-poor.

Even though gas giants are made of mostly hydrogen and helium, astronomers think the planets still require an initial core of heavy elements to attract lighter gases and grow.

Alan Boss, a planet-formation theorist at the Carnegie Institution for Science in Washington, D.C., said HIP 13044b is "big news," because it's such an anomaly in terms of its origins.

"This object ... is unlikely to have formed by the conventional mechanism of first building a massive core of rock and ice and then pulling on enough gas to form a true gas giant planet," said Boss, who was not part of the study team.

Study leader Setiawan agrees: "Now we have this finding, and it suggests maybe there are other mechanisms of planet formation around metal-poor stars that we don't know about."

http://www.ibtimes.com/articles/83760/20101119/milky-way-galaxy-jupiter-earth-su...

Welcome red giant new visitor to our galaxy!

By Balasubramanyam Seshan | November 19, 2010 5:06 AM EST
International Business Times

Visitors tend to visit our home at any time, but this time an immigrant red giant from another galaxy has arrived in our Milky Way. This happens to be a new planet at least the size of Jupiter that came from another galaxy and is orbiting a star called HIP 13044.

An exoplanet from another galaxy and its star. Artist's impression of the yellowish star HIP 13044 and, on the bottom right, its planet HIP 13044 b.

While this star is now in the Milky Way, researchers at the Germany's Max Planck Institute for Astronomy and the European Space Agency said that it originated in a separate galaxy that was later cannibalized by our galaxy. The planet lives 2,000 light years away inside the Helmi stream, a ring of ancient stars that cuts through the plane of the Milky Way.

Astronomers have detected over the last 15 years nearly 500 exoplanets orbiting ordinary stars in our cosmic neighborhood. Now, for the first time, astronomers have detected an exoplanet whose origin appears to lie outside our own Milky Way galaxy.

The host star is called HIP 13044 and the planet is known as HIP 13044b, which has a minimum mass of 1.25 times the mass of Jupiter. It lies around 2,000 light years from Earth in the southern constellation of Fornax (Furnace), the researchers said.

The planet was discovered with the radial velocity method which measures tiny wobbles of a star caused by a planet's gravitational pull. HIP 13044's wobbles were detected with the high-resolution spectrograph FEROS at the 2.2-meter MPG-ESO telescope at the La Silla European Southern Observatory in Chile.

The planet and its host star appear to have originated in a dwarf galaxy that was swallowed by the Milky Way galaxy between 6 billion and 9 billion years ago. Such galactic cannibalism is an ordinary occurrence in galactic evolution.

Typically, remnants of swallowed-up dwarf galaxies can be detected as ribbon-like arrangements of stars known as 'stellar streams'. In this case, HIP 13044 is part of the so-called 'Helmi stream'.

"For the first time, astronomers have detected a planetary system in a stellar stream of extragalactic origin. Because of the great distances involved, there are no confirmed detections of planets in other galaxies. This cosmic merger has brought an extragalactic planet within our reach," said Rainer Klement of the Max Planck Institute for Astronomy.

While the host star HIP 13044 was rather similar to our own Sun earlier on, it has since gone through the 'Red Giant' phase, in which a star cools and expands to hundreds of times the radius of the Sun, the researcher said. It has now settled down into another quiet phase powered by the nuclear fusion of helium, which is expected to last a few million years in total.

The fact that the exoplanet survived the red giant stage provides an intriguing glimpse of one possible fate of our own planetary system -- our Sun is expected to become a Red Giant in around five billion years.

Johny Setiawan and his colleagues expect the current close orbit of HIP 13044b was initially much larger, and that the planet migrated inwards during the star's Red Giant phase. Its present average distance to its host star is a mere 12 per cent of the distance between the Sun and the Earth, with an orbital period of only 16.2 days.

There is some evidence that some closer-in planets did likewise, and did not survive: "HIP 13044 is rotating relatively quickly for a star of this particular type. One explanation is that HIP 13044 swallowed its inner planets during the Red Giant phase, which would make the star spin more quickly," said Setiawan.

The team also studied HIP 13044b's parent star, which they said was similar to our sun. At about eight billion years old, the star is now in the red giant stage, a late phase of stellar evolution in sun-like stars.

The host star is a very ancient, very metal-poor star. The new planet's host star HIP 13044 appears to contain very few elements heavier than hydrogen and helium (extremely metal-poor) - less than any other star with planets.

According to astronomers, stars and their planets are made from the same initial building blocks, so if a star has few metals, the disk of material that surrounded the star when it was young -- and from which its planets are born -- was also metal-poor.

Although gas giants are made of mostly hydrogen and helium, astronomers think the planets still require an initial core of heavy elements to attract lighter gases and grow.

"It is a puzzle for the widely accepted model of planet formation of how such a star, which contains hardly any heavy elements at all, could have formed a planet," said Setiawan.