“It’s showtime....”
Posted on 06/09/2009 9:46:50 PM PDT by NormsRevenge
WASHINGTON (AFP) – A massive bright reddish star in the Orion constellation has mysteriously shrunk by over 15 percent in the last 15 years and astronomers have not yet determined why, according to a study released Tuesday.
Betelgeuse, considered a supergiant star, is so large that it would reach to Jupiter's orbit in our solar system. But at a radius of about five astronomical units, the star has shrunk in size since 1993 by a distance equivalent to Venus's orbit.
"To see this change is very striking," University of California, Berkley professor Charles Townes, who whon the 1964 Nobel Prize in physics for inventing the laser, said in a statement.
"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."
According to Townes, the star's size diminished "smoothly, but faster as the years progressed."
The findings were presented Tuesday at a meeting of the American Astronomical Society in Pasadena, California, and were based on readings collected at UC Berkeley's Infrared Spatial Interferometer (ISI) atop Mount Wilson in Southern California.
Edward Wishnow, a UC Berkeley research physicist who worked with Townes on the study, said the researchers did not know why the star was 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," Wishnow said.
Red supergiant stars are suspected to explode into type-II supernovas, cosmic explosions due to a massive star's internal collapse.
(Excerpt) Read more at news.yahoo.com ...
Sorry (LOL) I guess I must of contracted ADHD from one of my students this year.
AT post #618
here
http://www.freerepublic.com/focus/chat/2182204/posts?page=622#622
is a short doc about France likely to disclose by Friday that there ARE ET’s running around loose on earth . . .
Ping me if that happens, ever. Meanwhile, I think Betelgeuse may go supernova before that ever happens. Call me a Type II error addict. hehe
Although Betelgeuse is 600 light years away, that is still WAY too close for me to be comfortable with the idea of it turning supernova. That would be very bad for us.
There will be some heavy particles drift in eventually.
The ones to worry about are the close ones like Aldebaran, and any White Dwarf with an active binary feeding it within 100LY or closer.
I’ll ping the list.
I don’t think I have a list of naysayers to ping.
If you are on the UFO list, you should get pinged.
I knew what ADHD was a minute ago but then I got distracted and forgot.
No, I’m not on any of the UFO lists.
Today is Friday, so if such news comes out today, ping me. I honestly *would* be interested. But I’m not interested in being on the UFO list. Thanks though.
“It’s showtime....”
No sweat.
Will be at pottery many hours today.
Blessings,
Heh heh....;]
Gamma rays ARE light - light of even shorter wavelength (and higher energy) than X-Rays, therefore they travel at light speed.
Ping.
That is very interesting. Thanks for the ping.
Not at all. The “gas” shock wave will be impeded by many light years of impeding “material” (such as it is) and suffer from an inverse-squared decrease in energy as it comes toward us. The only real danger from a supernova this distant arises from the gamma rays IF AND ONLY IF they are focused in our general direction, which appears very unlikely in this case.
“That’s why I won’t do two shows a night anymore. I won’t. I won’t do it.”
He/she had me at concoted.
Supernova, rather than a nova.
http://en.wikipedia.org/wiki/Betelgeuse
Betelgeuse... (a Ori, a Orionis, Alpha Orionis) is a semiregular variable star located approximately 600 light-years away from Earth. It is the second brightest star in the constellation Orion and the ninth brightest star in the night sky. Although Betelgeuse has the Bayer designation alpha, Rigel (Beta Orionis) is usually brighter (Betelgeuse is a variable star and is on occasion brighter than Rigel). The star is a vertex of the Winter Triangle asterism.
Betelgeuse is a red supergiant, relatively luminous, and one of the largest stars known. For comparison, if the star were at the center of our solar system its surface might extend out to between the orbits of Mars and Jupiter, wholly engulfing Mercury, Venus, Earth and Mars. The angular diameter of Betelgeuse was first measured in 1920-1921 by Michelson and Pease using an astronomical interferometer on the Mount Wilson 100 inch telescope.
Astronomers believe Betelgeuse is only a few million years old, but has evolved rapidly because of its high mass. Some astronomers believe it may become a supernova within a timeframe where it could be observable by human civilization.
[okay, sometimes wiki-wacky is a confused mess]
http://en.wikipedia.org/wiki/Red_supergiant
Stars with more than about 10 solar masses after burning their hydrogen become red supergiants during their helium-burning phase. These stars have very cool surface temperatures (3500-4500 K), and enormous radii. The five largest known red supergiants in the Galaxy are VY Canis Majoris, VV Cephei A, V354 Cephei, RW Cephei and KW Sagittarii, which all have radii about 1500 times that of the sun (about 7 astronomical units, or 7 times as far as the Earth is from the sun). The radius of most red giants is between 200 and 800 times that of the sun, which is still enough to reach from the sun to Mars and beyond... The mass of many red supergiants allow them to eventually fuse elements up to iron. Near the end of their lifetimes, they will develop layers of heavier and heavier elements with the heaviest at the core... The red supergiant phase is relatively short, lasting only a few hundred thousand to a million or so years. The most massive of the red supergiants are thought to evolve to Wolf-Rayet stars, while lower mass red supergiants will likely end their lives as a type II supernova.
http://en.wikipedia.org/wiki/Wolf-Rayet_star
Wolf-Rayet stars (often referred to as WR stars) are evolved, massive stars (over 20 solar masses), which are losing mass rapidly by means of a very strong stellar wind, with speeds up to 2000 km/s. While our own Sun loses approximately 10-14 solar masses every year, Wolf-Rayet stars typically lose 10-5 solar masses a year.
Wolf-Rayet stars are very hot, with surface temperatures in the range of 25,000 K to 50,000 K. It is believed that the star in the galaxy NGC 2770 that exploded into a supernova on January 9, 2008 — SN 2008D, the first supernova ever observed in the act of exploding — was a Wolf-Rayet star.
http://en.wikipedia.org/wiki/Supernova#Type_II
When the core’s supply of hydrogen is exhausted, this outward pressure is no longer created. The core begins to collapse, causing a rise in temperature and pressure which becomes great enough to ignite the helium and start a helium-to-carbon fusion cycle, creating sufficient outward pressure to halt the collapse. The core expands and cools slightly, with a hydrogen-fusion outer layer, and a hotter, higher pressure, helium-fusion center. (Other elements such as magnesium, sulfur and calcium are also created and in some cases burned in these further reactions.)
This process repeats several times, and each time the core collapses and the collapse is halted by the ignition of a further process involving more massive nuclei and higher temperatures and pressures. Each layer is prevented from collapse by the heat and outward pressure of the fusion process in the next layer inward; each layer also burns hotter and quicker than the previous one — the final burn of silicon to nickel consumes its fuel in around one day, or a few days. The star becomes layered like an onion, with the burning of more easily fused elements occurring in larger shells. In the later stages, increasingly heavier elements undergo nuclear fusion, and the binding energy of the relevant nuclei increases.
http://apod.nasa.gov/apod/ap980419.html
Here is the first direct picture of the surface of a star other than our Sun. Taken by the Hubble Space Telescope in 1995, the atmosphere of Betelgeuse reveals some unexpected features, including a large bright hotspot visible below the center. Betelgeuse (sounds like “beetle juice”) is a red supergiant star about 600 light years distant, easily recognizable from its brightness and reddish color in the constellation of Orion. While Betelgeuse is cooler than the Sun, it is more massive and over 1000 times larger. If placed at the center of our Solar System, it would extend past the orbit of Jupiter. Betelgeuse is nearing the end of its life and will become a supernova in a perhaps a few tens of millions of years.
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