Posts Tagged ‘black holes’


 

 

Lynette Cook

This artist’s conception shows newly discovered planet Gliese 581g, which has a 37-day orbit right in the middle of the star’s habitable zone. The Gliese 581 system and its host red dwarf star is only 20 light years from Earth.

The recent discovery of Gliese 581g, an alien planet in the habitable zone of another star, has been an exciting development for scientists probing the galaxy for signs of extraterrestrial life. At least one claim of a possible signal from the planet has already surfaced – and been met with harsh skepticism among the science community.

Following the Sept. 29 announcement of the discovery of Gliese 581g, astronomer Ragbir Bhathal, a scientist at the University of Western Sydney, claimed to have detected a suspicious pulse of light nearly two years ago, that came from the same area of the galaxy as the location of Gliese 581g, according to the U.K.’s Daily Mail online. [Alien Planet Gliese581g: FAQ]

Bhathal is a member of the Australian chapter of SETI, a non-profit scientific organization that is dedicated to research, exploration and education in the field of astrobiology.

“Whenever there’s a clear night, I go up to the observatory and do a run on some of the celestial objects,” Bhathal told the Daily Mail. “Looking at one of these objects, we found this signal. We found this very sharp signal, sort of a laser lookalike thing which is the sort of thing we’re looking for – a very sharp spike. And that is what we found.”

“I know the scientist, and when he first announced it, I asked him for the details, and he wouldn’t send them to me,” astronomer and SETI pioneer Frank Drake told SPACE.com. “I’m very suspicious.”

Drake is credited with conducting the first search for signals from extraterrestrial intelligences 50 years ago as part of what was then called Project Ozma. He coined the famed Drake Equation to calculate the number (N) of alien civilizations with whom we might be able to communicate.

Further study would perhaps confirm or deny the supposed observation, but Drake thinks that the claim is likely a dubious one.

Strange signal, or phantom?

Bhathal claimed to have detected the puzzling signal in Dec. 2008, almost two years before researchers announced the Gliese 581g finding, and long before it was announced that habitable planets were found orbiting the star Gliese 581 itself.

“I’m not aware of the location that was claimed for the source of that light, and [Bhathal] refused to tell me where it came from,” Drake said. “I think it’s very unlikely that it came from the direction of Gliese 581.”

Gliese 581g is one of two new worlds that was discovered orbiting the red dwarf star Gliese 581, which is located about 20.5 light-years from Earth. In total, there is a family of six planets that has been found around Gliese 581. [Tour the six Gliese 581 planets.]

Steven Vogt, a professor of astronomy and astrophysics at the University of California, and his colleague Paul Butler of the Carnegie Institution of Washington announced the Gliese 581g finding in a press conference held by the National Science Foundation on Sept. 29.

About Gliese 581g

While there are six planets known to orbit around the parent star, Gliese 581g is the only one in the so-called habitable zone – a region where liquid water can exist. Astronomers have long-thought that the presence of liquid water, which accompanies life on Earth, could be a major ingredient for life on other worlds.

Observations have shown that Gliese 581g is between three and four times the mass of Earth. While it is larger than our planet, it is still classified as a nearly Earth-sized world. Its radius is between 1.3 and two times the size of Earth, scientists have said.

The planet has not been officially named yet (nor have any other worlds in the Gliese 581 system). But Vogt has given it the nickname “Zarmina’s World,” in honor of his wife.

* Alien World Tour: The Exoplanets Around Star Gliese 581

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i found this truly amazing there for im posting the whole thing..

could this be nibiru or planet X  ?

Mysterious radio waves emitted from nearby galaxy

There is something strange in the cosmic neighbourhood. An unknown object in the nearby galaxy M82 has started sending out radio waves, and the emission does not look like anything seen anywhere in the universe before.

“We don’t know what it is,” says co-discoverer Tom Muxlow of Jodrell Bank Centre for Astrophysics near Macclesfield, UK.

The thing appeared in May last year, while Muxlow and his colleagues were monitoring an unrelated stellar explosion in M82 using the MERLIN network of radio telescopes in the UK. A bright spot of radio emission emerged over only a few days, quite rapidly in astronomical terms. Since then it has done very little except baffle astrophysicists.

It certainly does not fit the pattern of radio emissions from supernovae: they usually get brighter over a few weeks and then fade away over months, with the spectrum of the radiation changing all the while. The new source has hardly changed in brightness over the course of a year, and its spectrum is steady.

Warp speed

Yet it does seem to be moving – and fast: its apparent sideways velocity is four times the speed of light. Such apparent “superluminal” motion has been seen before in high-speed jets of material squirted out by some black holes. The stuff in these jets is moving towards us at a slight angle and travelling at a fair fraction of the speed of light, and the effects of relativity produce a kind of optical illusion that makes the motion appear superluminal.

Could the object be a black hole? It is not quite in the middle of M82, where astronomers would expect to find the kind of supermassive central black hole that most other galaxies have. Which leaves the possibility that it could be a smaller-scale “microquasar“.

A microquasar is formed after a very massive star explodes, leaving behind a black hole around 10 to 20 times the mass of the sun, which then starts feeding on gas from a surviving companion star. Microquasars do emit radio waves – but none seen in our galaxy is as bright as the new source in M82. Microquasars also produce plenty of X-rays, whereas no X-rays have been seen from the mystery object. “So that’s not right either”, Muxlow told New Scientist.

His best guess is still that the radio source is some kind of dense object accreting surrounding material, perhaps a large black hole or a black hole in an unusual environment. Perhaps the phenomenon also happens occasionally in our galaxy, but is more common in M82 because it is a “starburst” galaxy – a cosmic cauldron where massive stars are forming and exploding at a much higher rate than in the Milky Way, creating a lot of new black holes.

Muxlow will report the discovery at the Royal Astronomical Society National Astronomy Meeting in Glasgow, UK, today.

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