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Betelgeuse Is Shrinking, Astrophysicists Report
The popular star is puzzling researchers

June 10, 2009

Over the past 15 years, the world-famous star Betelgeuse, after which even cartoons were drawn, has been constantly reducing its size, and astronomers are puzzled at why this is happening. At this point, existing explanations of this phenomenon are unsatisfactory. Overall, experts reported at the 214th meeting of the American Astronomical Society, held in Pasadena, California, the star had registered a significant drop in size, comparable to the distance from where Venus orbits the Sun. Despite this fact, the variations recorded in its brightness levels were not very significant, the scientists said.

“To see this change is very striking. We will be watching it carefully over the next few years to see if it will keep contracting or will go back up in size,” UC Berkeley Professor Emeritus of Physics Charles Hard Townes explains. The expert is known for his work in quantum electronics, and for the fact that he invented the fundamentals of masers (infrared lasers). He also got the Nobel Prize in Physics in 1964, as well as the Templeton Prize back in 2005, LiveScience reports.

Betelgeuse had a radius of about 5.5 astronomical units (AU) in 1993, which means that it was 5.5 times larger than the average distance between the Sun and the Earth, of about 150 million kilometers, or 93 million miles. Since those measurements, the star has contracted significantly, while maintaining roughly the same level of brightness. This type of behavior is very uncommon in a red supergiant such as this one, but some believe that it may be connected to the fact that the star has evolved very rapidly, in only a few million years. They also believe that it will collapse into a supernova soon, in a time frame that will allow for this event to be witnessed by human civilizations.

“But we do not know why the star is shrinking. Considering all that we know about galaxies and the distant universe, there are still lots of things we don't know about stars, including what happens as red giants near the ends of their lives,” UC Berkeley Space Sciences Laboratory Research Physicist Edward Wishnow adds. “Whenever you look at things with more precision, you are going to find some surprises and uncover very fundamental and important new things,” the 94-year-old, who plans to spend the next few years observing the star, explains.

http://news.softpedia.com/news/Betelgeu ... 3760.shtml

Will I read anything funnier today than "world-famous star"?

well, I had a major dream a couple months ago about what looked like a supernova in the night sky. Keep in mind, it may well have already gone up, this could be visible any day now.... or in a few hundred years or more.

http://en.wikipedia.org/wiki/Betelgeuse

So does a supernova happen instantaneously? Or in what passes for instantaneously in Betelguese's time scale?

And also (too lazy to look it up) how many lightyears is she away from us?

rrapt wrote:So does a supernova happen instantaneously? Or in what passes for instantaneously in Betelguese's time scale?

And also (too lazy to look it up) how many lightyears is she away from us?

it's so close the typical redshift techniques don't work. closed possibility is around 540ly out to maybe as far as 650ly. That's quite close as these things go, but since it's poles do not seem to be pointed directly at us, the expectation is that we would make it through the supernova A-OK, except for a major lightshow and perhaps some minor sat disruption. but then, who knows? If it's shrinking as fast as it sounds like it is, the poles could start wandering and may well have a wider high energy cone than expected.

They also believe that it will collapse into a supernova soon, in a time frame that will allow for this event to be witnessed by human civilizations.

What do they mean by this? Are they saying that one day there won't be human civilizations on earth? perish the thought.

Well, technically, yes. Billions of years from now the Earth will be an arid desert due to the Sun increasing in size.

Beetlejuice is shrinking??

rrapt wrote:So does a supernova happen instantaneously?

Wikipedia says... "The core collapses in on itself with velocities reaching 70,000 km/s" and "About 1046 joules of gravitational energy—approximately 10% of the star's rest mass—is converted into a ten-second burst of neutrinos; the main output of the event."

So, yes, the collapse is extremely fast, but the visual end of the explosion itself takes ten seconds or so, depending on the size of the star.

.

My whole life I've been kind of hoping this would happen, or rather that it happened the requisite number of 540 to 650 years ago, so that we see it now. Also, mildly nervous about it, since there's no certainty what the impact will be here. (Except that a great number of the religiously conditioned will try to fit it into their respective absurd schemata, like a squirrel who thinks the lightning is a personal message.)

.

Betelgeuse close-up reveals dying star

July 30

One of the world's biggest telescopes has captured a vast plume of gas and a mammoth boiling bubble on a red supergiant star set to explode in "the blink of an eye," astronomically speaking.

Betelgeuse has been around for a few million years, but the star's extreme size and luminosity mean the end is nigh, probably a few thousand years away.

The second-brightest star in the constellation of Orion, Betelgeuse is almost 1,000 times bigger than the sun. Astronomers say if Betelgeuse were at the centre of our solar system, it would encompass Mercury, Venus, Earth, Mars and the main asteroid belt, almost reaching Jupiter's orbit.

A team of astronomers using the Very Large Telescope — which actually consists of four very large telescopes sitting side-by-side on a mountaintop in Chile — collected more than half a million images of the star in January.

Jan Cami, a professor at the University of Western Ontario in London, was a member of a team led by the Paris Observatory's Pierre Kervella, who travelled to Chile for two days of observations and got a good look at a gas plume almost as big as our solar system. They could also make out fainter traces that may be two additional plumes, Cami says.

As the Earth's atmosphere can cause distortion in the stellar images the telescope sees, the team deformed the telescope's mirror for brief periods of time, a technique called adaptive optics. To freeze the star's apparent motion, they also used a short exposure time and advanced image processing techniques.




Huge star gets its close-up

This is the first time astronomers have used this combination of techniques on the Betelgeuse star, Cami says.

Betelgeuse is so bright it can damage big telescopes, but the team blocked much of the star's light. They wanted to use the Very Large Telescope because it can show faint objects and fine detail with greater sharpness.

Another group led by Keiichi Ohnaka of the Max Planck Institute for Radio Astronomy in Bonn, Germany, used a different viewing technique to map the movement of gas on the star's surface.

Ohnaka's group combined the light from the Very Large Telescope with that of a smaller telescope 48 metres away to produce a sharper image than would normally be possible.

"They obtained an image as sharp as what they would get with a 48-metre telescope," Cami said.

That team discovered a bubble of rising gas that corresponds to the location of the plume.

"It's absolutely spectacular," Cami says of the combined observations.
Betelgeuse expected to go supernova

Cami specializes in the chemical composition of material surrounding stars. He used the data from the telescope to identify elements in the plume.

"We know one of the chemical components is cyanide, which was surprising because we wouldn't have expected it."

The most important finding, though, is that the shape of the plume showed that Betelgeuse and supergiant stars like it are losing mass asymmetrically.

"It might help us understand how long it will take before the star explodes," Cami says.

Betelgeuse is a "textbook example" of a star that will soon become a supernova, and the new observations help astronomers as they try to understand what leads to the celestial explosions.

Cami said Betelgeuse will likely explode within thousands of years, an extremely short span of time by astronomical standards.

http://www.cbc.ca/technology/story/2009 ... -star.html

Col. Quisp wrote:

They also believe that it will collapse into a supernova soon, in a time frame that will allow for this event to be witnessed by human civilizations.

What do they mean by this? Are they saying that one day there won't be human civilizations on earth? perish the thought.

its a pretty safe bet actually.

man is something to be overcome.

[one way or the other]

JackRiddler wrote:.

(Except that a great number of the religiously conditioned will try to fit it into their respective absurd schemata, like a squirrel who thinks the lightning is a personal message.)

.

spoken like someone who has never had a conversation with a storm before.

From Wikipedia:

It is possible that Betelgeuse will become a supernova, which will be the brightest ever recorded, outshining the Moon in the night sky.

I wish I could see that.

Be careful what you wish for.

A rumor is floating around the Internet, that Betelgeuse is 'weeks' away from blowing, meaning that it has blown already and we may be about to see it. The source is the Life After the Oil Crash Forum where 'rbrgs' says:

I was talking to my son last week (he works on Mauna Kea), and he mentioned some new observations (that will no doubt get published eventually) of "Beetlejuice"; it's no longer round. This is a huge star, and when it goes, it will be at least as bright as that 1054 supernova...except that this one is 520 light years away, not 6,300...

When it collapses, it will be at least as bright as the full moon, and maybe as bright as the sun. For six weeks. So the really lucky folks (for whom Betelgeuse is only visible at night) will get 24 hour days, everybody else will get at least some time with two suns in the sky. The extra hour of light from daylight savings time won't burn the crops, but this might. Probably, all we'll get is visible light (not gamma rays or X-rays), so it shouldn't be an ELE. It's sure gonna freak everyone out, though.....

Then it will form a black hole, but we're too far away for that to matter.

The buzz is that this is weeks/months away, not the "any time in the next thousand years" that's in all the books.