--------- #1323 - Other Gamma Ray Sources and Mysteries?
- Attachment: Gamma Ray image
- What we “see” in our Universe is very limited, extremely limited. Our eyes can detect that part of the electromagnetic spectrum from about 400 to 700 nanometers wavelength. That is the wavelengths from blue light to red light and all the colors in between. We can use our radio receivers to detect the really long wavelengths. TV receivers, Microwave receivers detect other parts of the electromagnetic spectrum. Using only our eyes we are limited to the light form the Sun and the stars and the reflected light of the Moon and all that is around us in natural emitted and reflected light.
- Of course, technology has brought us many other man-made source of light. It all comes from electrons changing energy levels in atoms and emitting or absorbing electromagnetic radiation in return. The very shortest wavelengths are X-rays and Gamma Rays that are mostly emitted and absorbed by the nuclei of atoms rather than the electron shells of atoms. Technology has also brought us detectors that can “see” this part of the electromagnetic spectrum.
- Today we have a satellite in orbit that can detect Gamma Rays. It is the Fermi Gamma Ray Space Telescope. If we could “see” using these new detector’s eyes we would see flares spewing out from the surface of the Sun. We would see the accretion disks of high energy matter circling Blackholes. See Review #1321 to learn about the Gamma Ray Bubbles that came from the center of our galaxy.
- The telescope has identified 1,873 Gamma Ray emitting objects to date. Half of these are from active galaxies that have massive Blackholes at their centers. As these Blackholes swallow matter they emit massive amounts of high energy radiation. Many of these sources can not be seen with other parts of the electromagnetic spectrum. This is a mystery. Usually other parts of the spectrum are part of the emission, not just Gamma Rays. Other objects include Pulsars, Supernova remnants, Globular Star Clusters, and the center of our own Milky Way Galaxy. Still 1/3 of the catalog remains a mystery.
- Here are the top 5 sources that are found inside our Milky Way Galaxy.
-------------------- (1) The Crab Nebula in the Constellation Taurus the Bull. It is the remains of a supernova that exploded in 1054. It is 6,500 lightyears away. The original core of the star is now a super-dense neutron star called a Pulsar that spins and pulses 30 times per second. In the last 3 years the Gamma Ray emissions from the nebula has faded by 7%. Short lived Gamma Ray flares have been observed that are hundreds of times higher energies that the X-ray varieties. To account for this super-energy level the electrons near the Neutron Star must be accelerated to energies 10^15 times greater than visible light. That is 1,000 trillion times greater!
---------------------- (2) W44 is another supernova remnant thought to be 20,000 years old. It is located 9,800 lightyears away in the Constellation Aquila the Eagle. The Gamma Rays being detected are coming from the supernova shockwave that is colliding with surrounding gas clouds. Theory has it that high energy Cosmic Rays, which are accelerated protons, may be generated within the magnetic fields and then colliding with the shockwave. Because the protons are positive charges their paths get scrambled by these magnetic fields masking their origins. Astronomer are studying W44 to see it they can confirm this theory and the origins of the Cosmic Rays.
------------------ (3) V407 Cygni is a binary system with a White Dwarf star and a Red Giant star. The Red Giant is 500 times the size of our Sun. The binary is 9,000 lightyears away in the Constellation Cygnus the Swan. Gamma Ray flares are detected from the surface of the White Dwarf when gas from the Red Gant gets ripped away and explodes as it hit’s the super hot surface of the Neutron Star. The most recent explosion detected on March, 2010. This was totally unexpected as a Gamma Ray source by astronomers.
----------------- (4) Pulsar PSRJ0101-6422 in the Constellation Tucana the Toucan. This Pulsar is blinking in Gamma Rays at 400 times per second. Pulsars are Neutron Stars that are so dense that have the mass of the Sun in the size of Washington D.C. Lighthouse-like beams of radiation powered by the pulsar’s rapid rotation and strong magnetic field sweep across the sky with every spin. Astronomers have to be in the beam’s direction if it is to be detected. The pulses from this Pulsar are rotating at 400 times per second. This is as if Washington D.C. were spinning the fastest speed of a kitchen blender. Somehow it makes sense to visualize that.
------------------------ (5) 2FGL J0359.5+5410 is another Pulsar in the Constellation of Camelopardalis the Giraffe. These pulses have not been detected yet, probably because we are not in the beam path. Pulses at other wavelengths have not been detected either. However, the Gamma Ray spectrum resembles that of a Pulsar. We need more evidence so this source remains a mystery.
- Summarizing the Fermi Catalog to date, after 2 years of collecting Gamma Rays:
------------------------ 57% are Blazars
------------------------ 6% are Pulsars
------------------------ 4% are Supernova Remnants
----------------------- 1% are Non-Blazar Active Galaxies
----------------------- 1% are Globular Clusters, high mass binaries, and Normal Galaxies
------------------------ 31% are mysteries.
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RSVP, please reply with a number to rate this review: #1- learned something new. #2 - Didn’t read it. #3- very interesting. #4- Send another review #___ from the index. #5- Keep em coming. #6- I forwarded copies to some friends. #7- Don‘t send me these anymore! #8- I am forwarding you some questions? Index is available with email and with requested reviews at http://jdetrick.blogspot.com Please send feedback, corrections, or recommended improvements to: jamesdetrick@comcast.net.
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707-536-3272, Monday, November 7, 2011
--------- #1324 - How Politicians Use Math
- Attachment: none
- When it comes to math politicians and economists and financial managers do not have a good understanding of reality. They tend to use math to get the numbers they want. Physicists use math and revel at getting numbers they do not want. This was not expected? Why?
- The financial math models currently used on Wall Street grossly oversimplify things. So much so they loose touch with reality. A lot has to do with their use of math as a ‘normal distribution”. This model assumes the events are “ random” in nature. When events are outside a normal distribution they are ignored as outliers, not relevant to what they expect to see. They prefer to view systems in total equilibrium, while the train is going off the cliff. Here are some examples:
- The 2008 financial crisis, Lehman Brothers, and AIG financial firms go bankrupt ( although one was bailed out with our taxes). These firms were using financial models that assessed risk using the Gaussian Curve for a random distribution of the data. This is the same “ Bell Shaped Curve” your teachers used in grade school to grade papers. This always assumed you had a “normal” distribution of students.
- When these models are presented to the mathematically illiterate it results in a false sense of security. Not only will future results not match reality the unexpected result is “ inevitable” . Managers prefer numbers that “ feel good”, so there was no attempts to ask “ why?”
- The Gaussian distribution of truly random events clusters around an average ant tapers off in a predictable way. Above and below the average are “standard deviations” that can be calculated:
------------------- 1 sigma standard deviations around the average include 68% of the distribution of events. An event inside this distribution has a 68% chance of happening.
------------------ 2 sigma standard deviations around the average include 95% of the distribution.
---------------- 3 sigma standard deviations include 99.7% of the distribution. There is only 0.3% risk of the events not occurring inside this distribution around the average. OK, if it is outside 3 sigma it has almost no chance of happening. This is the model that was making elite managers feel good.
- The Gaussian model says that if an event is 100 standard deviations out it has a probability of 1 chance in 10^350 of occurring. That is a 1 followed by 350 zeros. That event is impossible right? If the math had included all the “outliers” in the data we find that the distribution more accurately follows the “Power Law” distribution , not the Gaussian distribution. The Power Law distribution has much longer tails. Looking at this same data we would say the event had a 1 in 100,000,000 chance of happening, not one in 10^350. If enough of these events occur the chances of seeing this event becomes much more likely. That is the way reality works. Rare events will happen, be prepared.
- When this Power Law distribution was used to predict downturns in the market on the Shanghai Stock Exchange the math predicted the market collapse in 2008 and 2009 within a few days of it actually happening.
- Power Law math is much messier so it tends to be ignored. Reality is even more complex than this model so it becomes even more difficult. The challenge becomes to figure out the “most important” ingredients to put in the model and deal with those alone. Simple is better but it has to be right. What causes a Power Law to apply to the model? Here is an illustration of how financial leverage creates greater uncertainties.
- Say you spot an under priced stock. You buy it. Normally a buy would push the price up a bit. Say, you were leveraging on borrowed money to amplify your returns. You borrowed more money to make more purchases. This tends to push the price even higher. Say the bank cuts you off as too high a risk This might force you to sell some of the stock. You might have to sell some other assets prematurely. As prices slide down others might begin selling as well. The amplification cause the tails of the distribution curve to broaden and extend outward with higher and higher risk. The result is a high probability of a crash.
- This same Power Law analysis can be done with CEO pay, with the number of bird sightings to estimate the population of a certain species, with very large firms affecting the market place, with out-of-control growth, with herding behavior of investors, all of these calculate incorrect results with based on the Gaussian models. Power Law models are an improvement but even that complexity is not enough. Thoughtful analysis of what is behind the numbers is needed. Are the important ingredients part of the model? Are outliers part of reality that need to be included? Math is a tool. You need to know how to use it. All models are an approximation of reality. Expect the unexpected to happen.
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(1)
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707-536-3272, Monday, November 7, 2011www.er.ethz.ch/fco
--------- #1321 - Milky Way’s Gamma Ray Bubbles
- Attachment: Gamma Ray image
- If your eyes could see in X-rays and Gamma Rays, not just the light waves, and, if you could step outside out Milky Way Galaxy and look at the galaxy disk that is 120,000 lightyears across, you would see the galaxy disk filled with stars, billions of stars and above and below the disk are giant bubbles that are an even greater mystery.
- These Gamma Ray bubbles stretch above and below the galaxy center at distances half the diameter of the galaxy, 50,000 lightyears. Each bubble is a perfect sphere forming a figure “ 8” touching at the galaxy center. Each bubble is 25,000 lightyears in diameter.
- These bubbles are not static, they are expanding at 2,200,000 miles per hour. Our Earth is 26,000 lightyears from the galaxy center along the plane of the disk. If we could see these Gamma Ray bubbles from where we stand they would extend 45 degrees above and below the galaxy plane. The connection at the center lies in the Constellation Sagittarius the Archer in the southern sky.
- The Constellation Sagittarius is in the shape of a “teapot”. The center of the galaxy and the location of the galaxy’s 4,000,000 Solar Mass Blackhole is right at the top of the spout of the teapot.
- If we measure the energy of these Gamma Rays they would be equivalent to 100,000 supernovae all exploding at a single moment. The temperature inside these bubbles is 7,000,000 degrees Fahrenheit.
- One theory from astronomers, that really have no idea what caused this, is that our galaxy’s Blackhole at one time spouted powerful jets. The jets shot out of the poles of the spinning Blackhole. The jets dispersed energetic material above and below perpendicular to the galactic plane. Somehow, bubbles of Gamma Rays formed out of these enormous energies. How this all happened is a mystery beyond belief and a tremendous new discovery for astronomers to ponder.
- Today our galaxy’s Blackhole is quiet and relatively small as galactic blackholes go. Our theory is mere speculation of our galaxy’s evolution in the distant past. See Review #1323 Other Gamma Ray Sources to learn more. An announcement will be made shortly stay tuned.
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707-536-3272, Sunday, November 6, 2011
--------- #1322 - Near-Miss Asteroid, November 8, 2011
- Attachment: Not so near miss
- Next Tuesday, Election Day, November 8,2011, an asteroid 400 meters in diameter will fly by Earth between us and the Moon traveling at nearly 42,000 miles per hour.
- The asteroid will miss the Earth by a mere 202,000 miles and just miss the Moon by 149,000 miles.
- Careful tracking of this asteroid tells us that we should not be in danger from this on for at least another 100 years. Yhewww! It will be back in 2041 but should miss us again next time as well.
- The next “known” big asteroid is not expected to have a close encounter until 2028. This one is expected to pass within 154,000 miles of Earth. These asteroids are tracked with some uncertainties. When they pass by other planets or other asteroids their paths can become altered. Stay tuned!
- This one we see on November 8 will be very dark and barely visible with a 6 inch backyard telescope. However, radar using the “chirp” mode should get good pictures down to 4 meter resolution. This should allow good definition of the asteroid’s shape. Other observations using infrared telescopes should learn about the surface roughness and the mineral composition.
- If this asteroid was really going to hit us we would not need to bother turning our clocks back for Daylight Savings Time. An announcement will be made shortly, stay tuned.
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707-536-3272, Friday, November 4, 2011
--------- #1319 - The Supernova of 185 A.D.
- Attachment: RCW-86 Supernova ( See footnote (1))
- See attached image of RCW-86 Supernova. This is one of about 8 supernovae explosions witnessed by the naked eye in recorded history. The Chinese recorded this one in the year 185 A.D. They called it the “Guest Star” and it remained in the night sky for 8 months.
- The image is a composite with the X-ray part of the spectrum translated down to blue and green colors so we can see them. The X-rays are being created in nebula debris by a tremendous shockwave that is expanding and smashing into the interstellar gas heating the atoms up to millions of degrees.
- The infrared part of the spectrum is translated up to yellow and red colors so we can see it too. The infrared radiation comes from dust in the interstellar medium that is also heated but only to 200 degrees below zero. Believe it or not that is warm compared to the background medium that is 270 degrees below zero, and only 3 degrees above Absolute Zero. The Cosmic Microwave Background is at 2.725 degrees Kelvin.
- The Guest Star Supernova explosion occurred 1,826 years ago. Astronomers studying the image today are trying to understand how the explosion occurred. It started with a White Dwarf star that was in a binary system with a companion star. the intense gravity of the densely packed White Dwarf star itself was probably the remnant of an earlier supernova. Its intense gravity is pulling gas and dust off the companion star steadily gaining mass.
- When the White Dwarf star reaches a mass of 1.4 Solar Mass ( 40% greater than the mass of our Sun), it explodes in a thermonuclear explosion. At the intense gravity of 1.4 Solar Mass the electrons in the shells of atoms collapse into the nuclei. The star implodes into the core and rebounds into a giant explosion. Before the explosion occurred the star had emitted smaller burps of material creating a smaller shockwave of wind that cleared out a cavity of very low-density surrounding the binary system.
- When the explosion finally occurred it expanded rapidly into this rarified cavity much faster than it would have in normal Type 1a Supernova explosions. This new finding has important implications for astronomers who use Type 1a Supernovae as “ standard candles” to measure the distances of galaxies throughout the Cosmos.
- RCW-86 is 8,000 lightyears away in the southern Constellation Circinis the Compasses. The explosion nebula today is 85 lightyears in diameter and occupies a spot in the sky that is slightly larger than a full moon. This is 2 to 3 times larger than astronomers would have expected for a supernova of this type having 2,000 years to expand.
- RCW-86 was the first supernova ever recorded. It is still telling us new things. More announcements will be made shortly, stay tuned.
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(1) http://go.nasa.gov/pnv6Oy
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707-536-3272, Thursday, November 3, 2011
--------- #1318 - Kepler’s Supernova
- Attachment: Composite image of supernova
- Johannes Kepler saw his supernova over 400 years ago. It occurred in the Constellation Ophiucus, the Serpent Bearer, just 20,000 lightyears away. Kepler had only his unaided eye to watch the new star that was brighter in the night sky than the planet Jupiter. It lasted for 18 months and is the last observed supernova in the Milky Way Galaxy.
- When the Supernova , SN1604, first exploded, first observed October 9, 1604, Kepler started his observations October 17. It was named after him because he wrote a book about his observations in 1606. The explosion sent a shockwave expanding into the interstellar gas medium around the star. The gas atoms heated to temperatures of millions of degrees. High energy particles created in this heat began emitting X-ray radiation. This X-ray spectrum is what was detected to create the composite image in the picture attached, see last paragraph.
- Astronomers studying the supernova remnants and debris have noted the presence of large amounts of the element iron. They also cannot detect any remnant star located at the core. Large massive-star supernova leave behind a Neutron Star or a Blackhole. Kepler’s Supernova seems to have evaporated everything. Normally this scenario would indicate a Type 1a Supernova. Type 1a supernova are created by a binary system where one star is a White Dwarf under 1.4 Solar Mass. The White Dwarf having greater mass than its companion star accretes gas and material from the other orbiting star. This accretion over time builds up the mass of the White Dwarf until it exceeds 1.4 Solar Mass. When this happens gravity collapses the star to its core creating a thermonuclear explosion we call a supernova.
- In Kepler Supernova’s case a strange phenomena is occurring. The explosion is expanding into a dense material rich in nitrogen. This would suggest a Type II Supernova which occurs in much more massive stars where layers of elements are expelled before the explosion.
- A Type II supernova occurs from a super massive star that sheds its outer layers of the layered elements before the explosion occurs. This counter diction was reversed again when astronomers carefully measured the ratio of oxygen to iron elements. This ratio suggested a Type 1a Supernova. To resolve this astronomers now believe this particular Type 1a supernova somehow came from a more massive star than unusual. Not, necessarily a star that had just reached exactly 1.4 Solar Mass.
- Type 1a supernova are used as “standard candles” of brightness to judge the distances of supernova and the galaxies they live in, or die in. A careful study is needed on this 400 year old explosion to better understand the mechanisms that create this expected luminosity. Astronomers are using these distance measurements to explain the Dark Energy that is expanding the Universe. Astronomers also view Type 1a supernova as the primary source of the amount of iron found in the Cosmos. A better understanding may change some previous “discoveries”.
- The Kepler remnant image uses red to represent the low-energy X-rays. The material around the star is dominated by the element oxygen that has been superheated from the explosion’s shockwave. Yellow is the color representing higher-energy X-rays coming from the element iron. Green is the medium-energy X-rays coming from other elements. Blue represents the highest-energy X-rays at the bow of the shockwave.
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(1) Johannes Kepler (1571-1630) was the son of a professional soldier. His grandfather was the mayor of his hometown. He got a religious education because having smallpox at 3 crippled his hands and weakened his eyes making him unfit for strenuous work. He received a Masters degree in 1591. He was brilliant at math and wound up a teacher of science at U. of Graz, Austria. In those days astronomers were supposed to be astrologers and he found himself giving horoscopes to the emperor and other rich elites. In 1598 he went to work in Prague with Tycho Brahe. When Tycho died in 1601 Kepler inherited all of his astronomical observation data. He really began studying the data more carefully when he witnessed “Kepler’s Supernova” on September 30, 1604. Kepler tried to fit Tycho’s data using Greek musical spheres and Plato’s five Platonic solids. After years of effort he finally discovered the ellipse that could exactly fit Tycho’s data. When the ellipse was used on Mar’s orbital data he found the Sun to be one focus of the ellipse. In 1609 he published his first book announcing, “ a line connecting the planet and the Sun will sweep over equal areas in equal times as the planet moves about its orbit“.
- Kepler’s ellipses put an end to Greek astronomy using celestial spheres. It remained for Isaac Newton to explain gravity and why the Sun controlled the orbits of the planets. In 1619 Kepler’s second book announced, “ the square of the period of revolution of a planet is proportional to the cube of its distance from the Sun.” Kepler wrote to Galileo about these theories and Galelio sent Kepler one of his first telescopes. Kepler continued his studies making improvements in the optics of telescopes. He used Napier’s logarithms in his calculations. He predicted the transit of Mercury across the face of the Sun that occurred in 1631. Kepler had 13 children and still found time to write a story, “Somnium” about a man who traveled to the moon. His manuscripts are preserved in the Pulkovo Observatory in Russia.
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707-536-3272, Tuesday, November 1, 2011
--------- #1316 - Comets, The Five We Have Visited?
- Attachment: Comets forming in accretion disk
- If you want to know what a comet is made of you have to go visit one, better yet visit 5. We have sent 4 separate spacecraft to visit comets. (See #1315 about visiting asteroids). These comets have been orbiting the Sun since the beginning of the Solar System and have pretty much remained unchanged. Studying them is like studying the raw material that our early Solar System evolved from. ( See #1303 How did the Earth get its water?)
- The Solar System evolved from a rotating disk of dust and gas. A cloud that gravity gradually pulled together. 99% of it ended up in the Sun But, some pieces broke off to form the planets and even smaller pieces formed the asteroids and the comets. The massive object at the center got so dense it ignited into nuclear fusion. The radiation of the nuclear fusion stopped the further collapse of gravity. The inner circle of the disk contained the heavier material that was most influenced by the pull of the Sun. This material became the 4 rocky planets and the rocky Asteroid Belt. The outer circle contained the more rarified gaseous clouds and formed the 4 gaseous planets and the Kuiper Belt of comets and a few Dwarf Planets including Pluto.
- The edge of the Asteroid Belt beyond Mars is called the “snowline” where liquid water began to freeze due to its distance from the Sun. Hydrogen gas freezes only at extremely low temperatures, so it remains a gas. Oxygen the same. But, when hydrogen and oxygen atoms combine into the molecule of water they form H2O. The snowline outward is where these water molecules began to freeze solid. These icy objects extend all the way out to the Oort Cloud that extends 5,000 to 100,000 AU distances from the Sun. 100,000 AU is 100,000 times farther than the Earth-Sun distance of 93,000,000 miles.
- The spacecraft mission to the Comet 81P/Wild found silicate grains that originally formed close to the Sun. The conclusion from this find was that the comet nuclei are formed from multiple locations in the proto-planetary disk, not just from debris in their current orbit. Some comets had unusual elliptical orbits bringing them closer and farther from the Sun.
- The relative abundance of different elements and molecules changes with the distance from the Sun. This can tell astronomers where the comets first formed. One of the chemical signatures used is the ratio of Carbon-2 and Carbon-3 to the amount of water, H20. The carbon likely came from the molecule acetylene (C2H2) Knowing this ratio tells us the comets first orbit.
- The spacecraft that visited Comet 9P/Tempel sent along a bullet to fire into the Comet surface and measure the debris that flew out of the crater. The crater was 165 to 500 feet in diameter. It was a big bullet. Some 5,000 to 10,000 tons of ice emerged from the impact along with an equal amount of rocks and dust. The debris was found to have an abundance of ethane (C2H6). As the debris fell back to the surface careful measurements allowed the calculation of the force of gravity and therefore the mass of the comet. Once the mass was known the calculation for density discovered the comet to be quite porous. Calculations showed 75% porous material extended 66 feet deep below the surface. Another conclusion made was that the comet was loosing 8 to 20 feet of surface material with each orbit around the Sun.
- Another spacecraft visited the Comet 103PHartley in November, 2010. Strangely it found softball-size chucks of ice surrounding the nucleus. These particles were 19 miles above the surface orbiting at 4 miles per hour. Another surprise was the high ratio of carbon dioxide to water ice. When findings do not match expectations it is the surprises that prove most interesting.
------------------------------------MISSION ----------- COMET ------------ DIAMETER
--------------- 1985 ----------- Giotto -------------- 1P/Halley ------------- 9.3 miles
--------------- 1998 ----------- DeepSpace 1 ------- 19PBorrelly ---------- 5.4 miles
--------------- 1999 ------------ Stardust ------------- 81P/Wild ------------ 3.4 miles
--------------- 2005 ------------- Deep Impact ------- 9PTempel ------------ 4.7 miles
--------------- 2007 ------------- Stardust-NExt------ 9PTempel ----------- 4.7 miles
--------------- 2010 ------------- EPOX1 ------------- 103PHartley --------- ?
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RSVP, please reply with a number to rate this review: #1- learned something new. #2 - Didn’t read it. #3- very interesting. #4- Send another review #___ from the index. #5- Keep em coming. #6- I forwarded copies to some friends. #7- Don‘t send me these anymore! #8- I am forwarding you some questions? Index is available with email and with requested reviews at http://jdetrick.blogspot.com Please send feedback, corrections, or recommended improvements to: jamesdetrick@comcast.net.
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707-536-3272, Tuesday, November 1, 2011
