Thursday, July 15, 2010

Betelgeuse-We hardly knew ye!

Note-the spacing is a bit off to say the least for this article! I tried to work with HTML code as much as I can which isn't much and got it a tad better-but still not right-apologies to reader!

Betelgeuse is a semiregular variable star whose apparent magnitude ranges between 0.2 and 1.2, the most for any first magnitude star. It is the ninth brightest star in the night sky located between 520 and 640 light-years from Earth.

Classified as a red supergiant, Betelgeuse is one of the largest and most luminous stars known. For comparison, if the star were at the center of our solar system its surface would extend past the orbit of Jupiter, completely engulfing Mercury, Venus, the Earth and Mars.

Betelgeuse is probably only between six and eight million years old. Its mass is so high- between 15 and 18 times that of our Sun-that it has evolved very rapidly as all massive stars do. For instance, our Sun may live about 10 billion years, and lower-mass stars than the sun can live from 15 billion to around 1 trillion years for the very lowest mass stars (around o.08% the mass of our sun).

Betelgeuse is the second brightest star in the constellation Orion (only behind Rigel AKA Beta Orionis). Betelgeuse marks the upper-right vertex of the Winter Triangle and center of the Winter Hexagon.

Recent ground-based infrared measurements of the disk of Betelgeuse gave a mid-infrared angular diameter of 54.7 (plus or minus 0.3 milliarseconds) in November 1999, slightly smaller than the typical visible-light angular diameter. These measurements ignored any possible contribution from hotspots, which are less noticeable in the mid-infrared, but factored in some limb darkening, whereby the intensity of the star's image diminishes near the edge, as the photospheric gas gets thinner.

It is difficult to define the precise diameter of Betelgeuse as the photosphere has no 'edge.' Instead the gas making up the photosphere gets gradually thinner with distance from the star.

On 9 June 2009, Nobel Laureate Charles Townes anncounced that the star has shrunk 15% since 1993 with an increasing rate. He presented evidence that UC Berkeley's Infrared Spatial Interferometer (ISI) atop Mt. Wilson Observatory had observed 15 consecutive years of stellar contraction. The average speed at which the radius of the star has been shrinking during the period is around 210-219 meters per second (m/s).

Despite Betelgeuse's diminished size, Townes and his colleagues, Edward Wishnow, pointed out that the star's visible brightness, or magnitude, which is monitored regularly by members of the American Association of Variable Star Observers (AAVSO), had shown no significant dimming over the same time frame.

The distance to Betelgeuse is not known precisely. The measurement of the optical parallax from space yield a distance estimate of 495 light-years, while parallax measurement using radio emission gives a longer estimate of 640 light-years. Assuming a compromise distance of 570 light-years, the star's diameter would be about 950 to 1,000 times that of the Sun! If the Sun were the size of a beach ball, Betelgeuse would be the size of a professional sports stadium!

Betelgeuse has most likely exhausted its supply of hydrogen and is currently generating energy by the thermonuclear fusion of helium into carbon and oxygen. On the Hertzsprung-Russell diagram, the star has moved off the main sequence and has swelled and cooled to become a red supergiant.

The future fate of Betelgeuse depends on its mass, as it probably contains more than 15 solar masses, it will continue to burn and fuse elements until its core turns to iron, at which point Betelgeuse will explode as a type II supernovae. During this event the core will collapse leaving behind a neutron star remnant some 20 km (the size of a city!) in diameter-in other words very very dense! However, if Betelgeuse is at the lighter end of estimated mass, it may instead contract to become a white dwarf.

Considering its size and age of 8.5 million years, old for its size class, Betelgeuse may explode within the next 1,000 years. Perhaps it has already exploded, and because we are around 570 light-years away, we just haven't gotten the news yet!

The stars unusual name spawned the 1988 film Beetlejuice, and script writer Michael McDowell was impressed at how many people made the connection. He added they had received a suggestion the sequel be named Sanduleak-69-202 after the former star of Supernovae 1987A. In August Derleth's take on H.P. Lovecraft's Cthulu Mythos, Betelgeuse is the home of the 'benign' Elder Gods. There has been much debate over the identity of the red star Borgil mentioned in the Lord of the Rings, with Aldebaran, Betelgeuse and even the planet Mars touted as candidates. Professor Kristine Larsen concluded the evidence points to it being Aldebaran, as it precedes Menelvagor (Orion). Astronomy writer Robert Burnham, Jr. proposed the term padparadaschah, which denotes a rare orange sapphire in India, for the star.

Jeff Wells notes in his most recent post at Rigorous Intuition, "Hey hey, We're the monkeys": "It [Betelgeuse] appeared above, completing the constellation of Orion, as the first homogines appeared below, creating the evolutionary branch that differentiates us from chimpanzees. Australopithecus was obolesced by increasingly sophisticated models of symbologic acuity, able to connect the dots of the night sky into pictograms of their world. And in due, deep time, Orion became our superlative, celestial representation."

The first gentleman pictured is Craig Horner-thanks to Michael for bringing this guy to my attention-much appreciated! The last gentleman pictured is the super-hot and gorgeous Anton Antipov-unfortunately I don't know who the others are. I am going to continue with the Kabbalah series, and just need some time to gather information. I will try to post about other subjects in between as much as I can. Peace and be well to anyone stopping by!
PS- can anyone tell me how to get a different template than the ones blogger provides? I am so tired of seeing the background for this blog. If it isn't too difficult to change, I would like to see something like I see at different blogs that I link to. If it is difficult -maybe I shouldn't even try with my 'puter skills-LOL!


X. Dell said...

One of the things I find amusing about cosmic thought is the fact that we're litterally looking at objects in the sky, some of which we see exactly as they were a hundred years ago--maybe even centuries ago.

BTW, seems to me you can fit a thousand beach balls inside a stadium:-)

Best, my friend.

Devin said...

Hi Xdell!!
From when I was very young that is one of the major things that absolutely fascinated me about astronomy- it is kind of like looking at an archaeology site in the sky as everything we can see -we are seeing at different times-we even see our own Sun as it was eight minutes or so ago!!
all the best to you my friend!!

X. Dell said...

I have often gone to alternate sources for blog template designs before FATTY so graciously made a custom one for me. They're cheap and plentiful on the Internet. I would advise that you set up a test blog to see how it works with your content before converting MFM.

Devin said...

Hey Xdell thanks so much for your comments -and the link and advice!!
the main thing that worried me is if I effed up and more or less deleted my whole blog while just trying to change the damn template - with my tech skillz I could see myself making some stupid mistake that did that -if it is indeed doable as I have heard it is -
I will check out the link - thanks so much for stopping by my friend!!