Cassini picture gallery of the planet Saturn

----------------------- # 1570 - Cassini visit’s the planet Saturn

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- Saturn is as famous as any movie star. There have been over 300,000 close up pictures taken in recent years. The photographer was the Cassini Spacecraft that was launched in 1997, orbited Saturn in 2004 and has sent us over 450 gigabytes of data.
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---------------- To see this pictures do a search on these addresses:
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www.DiscoverMagazine.com/Cassini-
http://discovermagazine.com/galleries/2013/march/porco-saturn-inside-look-cassini -

www.ciclops.org-
http://www.ciclops.org/index.php -
- Many interesting events were recorded during the Cassini mission One was a powerful storm that stretched 180,000 miles long across Saturn’s atmosphere. The storm crackled with blue lighting in the pale yellow light of the atmosphere. Saturn is a gaseous planet that is composed of 96% hydrogen and 4% helium.
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- Jupiter has hits Big Red Spot and Saturn has its Great White Spot another storm that is stationary and 6,000 miles in diameter. Saturn is 33% the mass of Jupiter. Its diameter is 10 times that of Earth and it is 10 times further from the Sun than Earth.
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- The cloud formation over the sought pole of Saturn is in the shape of a perfect Hexagon, that is 15,000 miles diameter. What could possible cause this geometric shape? The Hexagon rotates with the planet every 10 hours and 39 minutes. The winds on Saturn get to 300 miles per hour.
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- Saturn has 30 moons. The largest is Titan that is larger than the planet Mercury . Titan’s diameter is 3,200 miles compared to our Moon’s 2,160 mile diameter. Titan’s methane atmosphere has winds blowing 250 miles per hour. There are liquid lakes of frozen methane and ethane gas. The surface is -290F and the atmospheric pressure is 147% that of Earth’s.
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- Cassini traveled 3,850,000,000 miles to get to Saturn in 2004. The spacecraft dropped a probe, Huygens, into the atmosphere of Titan in 2005. Pictures of the surface were taken before the probe landed near a methane lake. ( See the gallery of pictures mentioned above. )
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- Cassini flew through the plumes of water jets spouting out of the moon Enceladus. The salty liquid water was analyzed and fount to contain organic compounds. There pictures of this and many other moons:
-
------------------------------ Prometheus
------------------------------ Epimetheus
------------------------------ Janus
------------------------------ Telesto
------------------------------ Helene
------------------------------ Hyperion - that has such low density it must be a sponge.
------------------------------ Phoebe - that has a backward orbit compared to the other moons.
------------------------------ Mimas - 250 miles in diameter
------------------------------ Iapetus - 900 miles in diameter but shaped like a walnut with a raised ridge at its equator the extends 6 miles high.
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- The rings of Saturn extend out 46,000 miles and are composed of mostly water ice crystals and rock-ice chunks. Some as big as an automobile. The ring is only 5 meters thick. For comparison if Earth had rings extending to the Moon it would be only 1 inch thick.
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- See the gallery of pictures for a “real trip.” Also, for more reviews request : #1332, #1271, #1252, # 661
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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 upon request. Some reviews are at http://jdetrick.blogspot.com Please send feedback, corrections, or recommended improvements to: jamesdetrick@comcast.net. ---- “Jim Detrick” -- www.facebook.com, -- www.twitter.com, -- 707-536-3272 Thursday, February 28, 2013

Voyagers incredible journey thru the solar system

----------------------- # 1569 - Voyager Spacecraft tour the Solar System
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- Voyager spacecraft were launched in 1977, 5 years after we moved to Santa Rosa and my youngest daughter turned 1 year old. Today the spacecraft are still operating after 35 years and are about to exit the Sun’s gravity and visit outer space. Voyager is traveling 37,000 miles per hour on this incredible journey.
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- The voyager mission was an idea hatched by two young mathematicians. They were doing the math to determine if a spacecraft could save fuel by using the gravity push of the outer planets. In 1965 the calculations demonstrated that a single launch of two spacecraft could pass by the four giant gas planets, Jupiter to Saturn to Uranus to Neptune.
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- In order to take advantage of this planet alignment the launch had to occur in 1976 to 1979. If we missed this window the next opportunity would wait until 2153.
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- March 1979 Voyager passed by Jupiter. Its most amazing discovery was the moon Io. Io was not the cold rock moon expected but a dynamic, volcanic moon covered in resurfaced orange lava. The heat is generated by the tidal forces of Jupiter’s immense gravity.
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- Later discoveries by other missions have found Jupiter’s moon Europa covered in a thick sheet of ice hiding a massive ocean that may even harbor life.
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- November 12, 1980, Voyager passed by Saturn and detailed pictures of not 4 rings but 10,000 very narrow rings circling the planet. The rings consisted of chunks of ice and ice-covered rocks. The rings closer to Saturn were traveling faster than the rings further from the planet. Saturn’s moon Titan was found to have a dense atmosphere. The Cassini mission that followed obtained the first images of Titan’s surface below this dense atmosphere.
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- August 1981 the rotating platforms holding cameras on the spacecraft seized up due to depleted lubrications. After that the spacecraft had to be pointed where images were to be taken.
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- January 24, 1986 Voyager discovered 10 new moons orbiting Uranus. The most interesting moon was Miranda that had a surface of strange new geology.
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- August 1989 Voyager flew by Neptune’s north pole at only 3,045 miles altitude. The clouds covering the pole were composed of frozen methane gas. When Voyager passed by the moon Triton nitrogen geysers were discovered shooting out of the surface.
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- When voyager was 3,500,000,000 miles away it turned and took a picture of Earth, a pale blue dot.
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- 2004 Voyager exited the Sun’s solar wind where the wind slowed to below the speed of sound. In April 2010 the spacecraft left the solar wind altogether and is crossing the outer boundary of the Solar System venturing into interstellar space.
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- The intensity of cosmic radiation is increasing as the spacecraft enters outer space and leaves the protective shield of the Sun’s magnetic field. Voyager is now 11,500,000,000 miles from Earth. We say goodbye after 36 years of an exciting voyage. An announcement will be made shortly, stay tuned.
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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 upon request. Some reviews are at http://jdetrick.blogspot.com Please send feedback, corrections, or recommended improvements to: jamesdetrick@comcast.net. ---- “Jim Detrick” -- www.facebook.com, -- www.twitter.com, -- 707-536-3272 Wednesday, February 27, 2013

Cosmic Rays and Gamma Rays , an Update?

----------------------- # 1568 - Cosmic Rays and Gamma Rays, an Update.

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- Gamma Rays are rays of high energy light, electromagnetic radiation. They contain energies of greater than 3,000,000 electron volts. Their frequency of oscillation is very high, greater than 30,000,000,000,000,000,000,000 cycles per second ( 10^22), and their wavelengths are very short, less than 0.00001 nanometers. ( 10^-14 meters). This temperature translates to 290,000,000,000 degrees Kelvin, ( T = 0.0029 / wavelength). Energy = Planck’s Constant of Action * frequency = 6.63*10^-34 * frequency in Joules. ( E = h*f)
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- Cosmic Rays are not rays at all, they are particles. High speed particles that carry Kinetic Energy = ½ * mass * velocity^2. These particles are the charged particles of atoms, nuclei and electrons. They were discovered in 1912 as tiny bits of matter traveling in the atmosphere at nearly the speed of light. Their tracks were seen in cloud chambers. They were discovered to be electrically charged because they were deflected with a magnetic field, much like a cathode ray tube operates a television.
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- Most Cosmic Rays pass through the Earth without touching anything. But, some can encounter atoms, some of these enter the human body causing mutations in tissue. Some can hit a computer chip and cause errors in computer memories. Some enter a telescope and cause an unwanted streak across a CCD image.
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- When Cosmic Rays hit air molecules they create a shower of billions of electrons, muons, and other fundamental particles, positrons, and pions. This is much the same as what happens in a particle accelerator.
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- High energy Cosmic Rays can carry 10^20 electron volts of energy. That is 10,000,000 times greater that can be created in a particle accelerator, the Large Hadron Collider at CERN, Switzerland. This energy level from a small particle is equivalent to a tennis ball traveling 53 miles per hour.
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- High energy Cosmic Rays are not common, striking a square mile area every 39 years. Of course the Earth has a lot of square miles but where to put an observatory to catch these rare events?
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- The high deserts of the Andes Mountains in Argentina, bordering Chile. The telescope is a grid of water tanks spread over 1,200 square miles. 1,600 water tanks each holding 3,170 gallons of water. When a high speed cosmic ray enters the water it is traveling faster than the speed of light in water. This creates an electromagnetic shock wave and a flash of blue light.
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- All of the water tanks contain light detectors that can record the Cosmic Ray’s arrival within nanoseconds.
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- In addition to the water thanks there are 4 buildings designed to detect fluorescence nitrogen. High energy nitrogen atoms emit an ultraviolet glow.
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- These “telescope” detect several thousand Cosmic Rays and one high energy ray every 60 days. By comparing the timing and the trajectory angles astronomers can triangulate the source within 3.1 square degrees. ( The Full Moon is 0.5 square degrees.) Low energy Cosmic Rays get deflected by the Earth’s magnetic field but the high energy Cosmic Rays tend to travel closer to a straight line.
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- Theory is that these high energy Cosmic Rays originate in super massive Blackholes at the center of most galaxies. In falling material spirals around the Blackhole creating an accretion disk. The rotating plasma of charged particles create a friction generating heat to millions of degrees. Jets of this material shoot out the poles.
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- Galaxy M87 is being studied to confirm this theory, but, we need more data. Most Cosmic Rays are protons but some may even be iron nuclei. Heavier nuclei could contain much higher kinetic energy, but, the math still does not explain these exceedingly high energies. The mystery remains.
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- The average energy Cosmic Rays that are mostly protons are now confirmed as originating in supernovae explosions. The evidence comes from 4 years of data accumulated by the Fermi Gamma Ray telescope.
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- Supernovae shockwaves accelerate protons, the nuclei of hydrogen atoms, to near light speed. When these nuclei collide with other atoms they emit a unique fingerprint of Gamma Rays. 90% of the Cosmic Rays entering Earth’s atmosphere are these protons.
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- This has been a difficult study because protons are positively charged particles and when they enter Earth’s magnetic field their trajectories are deflected with a right angle force. This makes it almost impossible to determine which direction they originated from. The proton collisions near the supernova source have provided the indirect evidence that this was the source. Gamma Rays travel in a straight line as high energy light that is unaffected by magnetic fields.
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- Looking in the plane of our Milky Way astronomers have detected over 500 sources of Gamma Rays exceeding 10 billion electron volts. When a Blackhole accretion disk pole and jets are aimed directly at us we see the bright beam of Gamma Ray light.
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- These Gamma rays travel across billions of lightyears to reach us. They pass through and collide with the extragalactic background light creating pairs of matter - anti-matter, electrons and positrons. The Gamma Ray signal disappears when the pair production of matter-anti-matter happens.
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- The farthest galaxies are missing their high energy Gamma Rays ( >25 GeV) due to this attenuation process. By measuring this attenuation astronomers are able to calculate the average density of stars in the cosmos. There are an average of 1.4 stars fro every 100 billion cubic lightyears. They have concluded the star formation reached its peak when the Universe was 3 billion years old. Star formation has been on the decline the last 10 billion years.
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- There are still many mysteries to solve with Gamma Rays and Cosmic Rays. Astronauts report seing flashhesof light caused by Cosmic Rays entering the brain. We need to learn more about the health affects on space travelers.
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- The Crab Nebula has flashes of Gamma Rays that grow to 30 times normal and last for several days. The flashes exceed 100 million electron volts. This may have something to do with a massive magnetic field suddenly switching polarity. Mysteries remain. Announcement will be made shortly , stay tuned.
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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 upon request. Some reviews are at http://jdetrick.blogspot.com Please send feedback, corrections, or recommended improvements to: jamesdetrick@comcast.net. ---- “Jim Detrick” -- www.facebook.com, -- www.twitter.com, -- 707-536-3272 Sunday, February 24, 2013

Russia Meteor on Valentine's Day?

----------------------- # 1567 - The Russian Meteor

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- Valentine’s Day was a real surprise for many people in Russia. February 14, 2013, a 10,000 ton meteor blasted through the atmosphere. The fireball was traveling 40,000 miles per hour. The shockwave created when the meteor hit the atmosphere blew out glass windows in over 3,000 buildings, over a 1,000 square kilometers. Over 1,000 people were injured. Mostly glass cuts, one with a broken back. People instinctively went to the windows to see what caused the giant flash of light. They were standing in front of the windows when the shockwave reached them.
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- How often does an event like this happen?
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- After tracking data for decades astronomers can predict that asteroids of 4 meters diameter or larger enter the Earth’s atmosphere twice each year, on average. This particular meteor was 17 meters in diameter.
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- The surface of the Earth is 72% oceans and 28% land. On the land, only 3% is inhabited. The total surface of the Earth is 500,000,000 square kilometers.
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- If only 3% or the 28% is inhabited and only 2 events occur each year then 0.84% of the Earth’s surface has human eyes there to see it. 0.8% is 1 / 125 ,so, you would have to wait 125 years to see 2 events, or 62 years to see one event. For an average human lifetime you would likely see one of these meteors. Of course, we are not counting webcams, smart phones, surveillance cameras, etc., just naked eye sightings.
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- The Kinetic Energy of the meteor this size and this fast is astounding.
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------------------------ KE = ½ mass * velocity^2
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------------------------ One ton is 1,000 kilograms. And, one ton of dynamite, TNT, explodes with 4.2*10^9 Joules of energy.
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----------------------- The mass of the meteor was 10,000 tons = 10 million kilograms
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----------------------- The velocity was 40,000 miles per hour = 18 kilometers per second.
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--------------------- Kinetic Energy = ½ * (10^7 kilograms) * ( 1.8*10^4 m/sec)^2
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-------------------- KE = 1.62*10^15 Joules.
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------------------- This is equivalent to 386,000 tons of TNT which is 10 times the energy of an atomic bomb. If it hit directly and released all that energy it would be equivalent to 10 atomic bombs going off all at once.
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- Happy Valentine’s Day, Jim
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(1) Some footnotes about Joules of Energy. The meteor crater in Arizona, 4,000 feet in diameter, 600 feet deep, was created by a meteor with 1,300 *10^15 Joules of energy. That is 800 times more energy than the Russian meteor.
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- The Hiroshima Bomb released 0.084 * 10^15 Joules.
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- The largest H-Bomb tested in 1961 released 240*10^15 Joules.
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- The Earth’s rotational energy is 10^30 Joules.
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(2) The Big Bang released 10^68 Joules. How do they know that? The assumption comes from the total number of protons and neutrons in the Observable Universe to be 10^78. Each particle containing 10^9 electron volts of energy. This ignores gravitational energy and the 90% Unobservable Universe and anti-matter when all added together the total energy is zero Joules. Zero is an amazingly Big number.
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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 upon request. Some reviews are at http://jdetrick.blogspot.com Please send feedback, corrections, or recommended improvements to: jamesdetrick@comcast.net. ---- “Jim Detrick” -- www.facebook.com, -- www.twitter.com, -- 707-536-3272 Wednesday, February 20, 2013

Supernovae made us what we are?

----------------------- # 1566 - Supernovae are what we are made of!

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- Supernovae, stars that explode when they can no longer continue fusion radiation, are rare events. They are likely to happen only once per year in our Milky Way Galaxy. But, in the Observable Universe the event happens every second.
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- There are 100 billion galaxies, with 100 billion stars each. That is 10^22 stars that represent all the lifetimes of stars. That is more stars that all the grains of sand on the beaches of the planet Earth.
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- These are the same stars that have created the calcium in your bones, the iron in your blood, the potassium in your nerves. The iron in your blood could contain atoms that are 8 billion years old. When the cores of stars create fusion up to iron and nickel they stop radiating pressure against gravity. These two are the heaviest elements that are created with an excess of energy after fusion. Heavier elements are still created by immense gravity pressure by their fusion absorbs energy rather than releasing it. Therefore, the star continues to collapse into its core creating the 87 heavy elements.
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- When massive stars collapse to their core the collapse rebounds into a massive explosion. A supernova. The heavy elements that were created get spread out across the cosmos. These elements become the interstellar medium that in turn creates the next generation stars. What is left behind at the core is a neutron star or a Blackhole.
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- Supernovae explosions are so bright they have been seen by astronomers that are 12 billion lightyears away. The only brighter explosion is called a Gamma Ray Burst that pointing directly at us is 13 billion lightyears away. That is from a Blackhole that is exists only 700 million years after the Big Bang.
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- On March 19, 2008, 11:13 Pacific Time, looking at the Constellation Bootes you could have seen a Gamma Ray Burst with the naked eye. It was a Burst of X-rays and Gamma Rays but also visible light rays of magnitude 5.3. The bright light lasted for 50 seconds before diminishing. GRB080319B was 7.5 billion lightyears away. It was the farthest thing a human eye has ever seen. The polar jet of the Burst was aimed directly at us. The Blackhole the created the Burst was born over 2 billion years before our Sun was born.
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- 15 times supernovae have been observed before the exploded thanks to archived records of the sky. Novae are less bright than supernovae and occur when a smaller star transfers matter into a White Dwarf star that are in a binary system. RS Ophiuchi is a binary system that goes Nova every 20 years.
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- Using spectrographs to detect the elements in a supernova explosion have defined two types of supernovae:
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--------------- Type I Supernovae have little evidence of hydrogen
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--------------- Type II Supernovae have an abundance of hydrogen in their explosion.
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- There are 3 sources of energy in the rapidly expanding gas of a supernovae:
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------------------ (1) Radioactive decay of freshly synthesized elements, such as
Nickel-56.
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------------------- (2) The expanding shockwave heating the stars hydrogen atmosphere.
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------------------ (3) The interaction between the ejecta and the hydrogen gas.
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- There are sub categories of Types I and II supernovae: Type Ia is the brightest due to its abundance of radioactive elements. The explosion involves the total destruction of the White Dwarf Star.
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- Our Sun is not massive enough to become a supernova. When it exhausts its hydrogen fuel in 10 billion years it will fuse helium into carbon and oxygen and then stop. There is no more mass left to provide the gravity to continue the fusion process.
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- More massive stars do not end their fusion process, carbon and oxygen fuse into neon , silicon, iron-nickel. Once a star sues iron further fusion absorbs energy rather than releasing energy. The star collapses to the core and rebounds into a supernova explosion.
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- Gamma Ray Bursts occur about once a day in the Observable Universe. These are flashes of energy peaking in the Gamma-Ray part of the electromagnetic spectrum. Short Bursts lasting a few seconds are created when Neutron Stars merge. Long Bursts lasting minutes are the mergers into Blackholes. The Gamma -Ray Burst that was detected September 16, 2008, was 12.2 lightyears away. Gamma Rays are particles not rays, though the misnomer has stuck, were traveling 99.9999 percent the speed of light.
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- Here is how the different supernovae are identified by their light spectrum:
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---------------------------------- Hydrogen -------- Helium --------- Silicon -----------
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-------------- Type I ------------- No ------------- No --------------- No -----------
-------------- Type Ia ------------ No ------------- No --------------- Yes -----------
-------------- Type Ib ------------ No ------------- Yes -------------- No -----------
-------------- Type Ic ------------ No ------------- No --------------- No -----------
-------------- Type II ------------ Yes ------------- No --------------- No -----------
-------------- Type IIb ----------- Yes ------------ Yes -------------- No -----------
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- The supernovae debris from these explosions ends up in an interstellar dark cloud that condenses further into nebulae like the Orion Nebula that are star factories of the next generation stars. The density of the Orion Nebula is only equivalent to 150,000,000 hydrogen atoms per cubic meter. We are living in one of the densest parts of the Universe when measure the density of gases and the interstellar medium. The Earth atmosphere contains the equivalent of 7.5*10^26 hydrogen atoms per cubic meter.
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------------------------- Density = Mass / Volume
------------------------ Mass of Earth’s atmosphere = 5.1*10^18 kilograms
------------------------ Volume of Earth’s atmosphere = 4.2*10^18 meters^3
----------------------- Density = 1.21 kg / m^3
---------------------- Hydrogen atom = 1.6*10^-27 kilograms
---------------------- Density of Earth’s atmosphere = 0.76*10^27 H/m^3
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- Comparing densities across the gaseous cosmos:
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---------------------- Density of Earth’s atmosphere ==== 0.76*10^27 H/m^3
---------------------- Red Supergiant Betelgeuse ========= 1.1*10^25
---------------------- Surface of the Sun =============== 1.3*10^23
---------------------- Atmosphere of the Moon =========== 3.3*10^15
---------------------- Solar Corona =================== 6.2*10^13
---------------------- Interstellar Dark Cloud ============ 1.2*10^11
---------------------- Orion Nebula =================== 1.5*10^8
---------------------- Solar Wind inside Earth orbit ======= 20,000,000
---------------------- Milky Way Galaxy =============== 81,000
---------------------- Van Allen Radiation Belts =========== 53
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- We are living in and made of star dust and gas. When you look at the night sky and see those stars say “ that is where I came from”. We have watched the wobble of these stars in our Galaxy and found 1,115 other planets to date. There are many more. Is there anyone anywhere else saying the same thing, “ that is where I came from”. An announcement will be made shortly, stay tuned.

How fast must the satellite travel to stay in orbit?

----------------------- # 1565 - Math - How fast is that satellite?

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- Gravity Probe B is a satellite in orbit 400 miles up. ( See Review # to learn the Gravity Probe B mission). How fast must the satellite be going in order to stay in this orbit. A satellite in orbit is weightless because it is continuously falling around the Earth. Its orbit is falling around the curvature of the Earth. The rate of falling is determined by the acceleration of gravity, not the mass of the satellite. It is a constant. The rate of falling is the same for every mass that is in free fall and is at the same distance from the center of gravity. The acceleration of gravity near the Earth is 32.2 feet per second per second. (that s 9.8 m/sec^2)
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- The satellite , like the Moon, and the Planets obey Kepler’s laws of motion. The cube of the radius of orbit is proportional to the square of the period of orbit. Let’s start with the Moon, that is also in free fall around the Earth:
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------------------ The period of the Moon’s orbit is 27.32 days.
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------------------ The radius of the Moon’s orbit is 239,509 miles.
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- The cube of the period is proportional to the square of the period:
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- ------------------ (239,509 )^3 = K* ( 27.32 days)^2
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-------------------- 13/57 *10^15 = K * (7.464*10^2)
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- “K” is the constant of proportionality and we do not have to know that to solve the period for the satellite. We know that regardless of mass the ratios are the same.
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-------------------- Period for the satellite = Ts
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-------------------- Radius of orbit for the satellite is 400 miles plus the radius of the Earth 3957 miles equals 4,357 miles.
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- Now equate the two ratios and solve for Ts:
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-------------------- (4.357*10^3)^3 / 92.39509 *10^5)^3 = Ts^2 / (27.32)^2
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-------------------- 6.02*10^-6 = Ts^2 / 7.46*10^2
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------------------- Ts^2 = 44.93*10-4
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-------------------- Ts = 6.7 *10*-2 days
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-------------------- Ts = 1.61 hours ( 96.6 minutes )
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- The time for one complete orbit of the satellite is 1.61 hours. Now if we know the distance traveled in one complete orbit we can calculate the speed.
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- The distance of the orbit is the circumference of a circle which is 2 * pi * r. The velocity of orbit is distance / time.
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------------------ v = d / t = 2*pi *r / t = 2*pi*(4,357 miles) / 1.61 hours.
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------------------- v = 17,004 miles per hour.
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- However, this assumes we have a perfect circle for an orbit. What would be the effect if the satellite had a slightly elliptical orbit? An elliptical orbit requires that it travel a greater amount of distance in the same amount of time, so it must be going faster. Can we do this calculation without assuming the perfect circle orbit?
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- With the elliptical orbit the radius of orbit, r, changes with the function of time, t. If we construct a coordinate plane with the radius connected from the center of the Earth to the point on the orbit , we can make the radius to to be hypotenuse of a right triangle.
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----------------- hypotenuse = r
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----------------- opposite side = r * sin a, where “ a “ is the angle
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----------------- adjacent side = r cos a
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--------------- Using the Pythagorean Theorem: r^2 = (r*sin a)^2 + (r*cos a)^2
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- The radius is rotating as the points move around the elliptical orbit. The radius is a function of time, r(t), depending on the angularly velocity of rotation. The angular velocity = dc / dt. The rate of change of the angle with time. Restating the distance equation in terms of changes with time:
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--------------------- r(t)^2 = (r * sin da /dt * t )^2 + ( r*cos da/dt * t)^2
-
- The speed of the satellite is constant, but, the velocity of the satellite is constantly changing. Velocity is the rate of change of distance. v(t) = dr /dt. If we take the derivative of both sides of the above equation:
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---------------- v(t)^2 = ( dr/dt)^2 = r^2 cos a^2 (dc/dt)^2 + r^2 *(- sin a)^2 ( dc/dt)^2
-
- Where: the derivative of sin a = cos a dt
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- Where: the derivative of cos a = - sin a dt
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- Speed is the absolute magnitude of velocity. So, the square of velocity gets us an absolute magnitude and is equivalent to speed.
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------------------------ (cos a)^2 + (sin a)^2 = 1
-
- Again this is the Pythagorean theorem: opposite^2 / r^2 + adjacent^2 / r^2 = 1
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------------------- v(t)^2 = r^2 ( da/dt)^2
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------------------ v = r * da/dt
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------------------- velocity = radius * angular velocity
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------------------ (da/dt)^2 = v^2 / r^2
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- Acceleration is the rate of change of velocity. acceleration = dv / dt = r * (da/dt)^2
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------------------------------ acceleration = r * v^2 / r^2
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------------------------------ acceleration = v^2 / r
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----------------------------- In the case of a satellite in continuous orbit the acceleration of orbit must balance with the acceleration of gravity, g.
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-------------------------------acceleration = g = 32.2 feet/sec^2
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------------------------------ v^2 = g*r
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- The constant acceleration of gravity near the Earth is 32.2 feet per second per second, or 79,036 miles per hour ^2
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--------------------------- v^2 = 32.2 feet /sec^2 * 4.357*10^3 miles * mile / 5,280 feet * (3600 sec)^2 / hour ^2
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-------------------------- v^2 = 344.4 *10^6 miles^2 / hours^2
-
------------------------- v = 18,557 miles per hour.
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- The assumption here is that the acceleration of gravity is 32.2 feet /sec^2 at 400 miles altitude. Assuming that is near to the Earth. The other assumption was that the orbit was a perfect circle. Both need some tweaking to get a more accurate answer to how fast the satellite is traveling. All velocity is relative depending on your assumptions. But, the satellite must be traveling about 18,000 miles per hour. It will be traveling slightly faster if its orbit gets closer to Earth and slightly slower when farther away from Earth.
-
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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 upon request. Some reviews are at http://jdetrick.blogspot.com Please send feedback, corrections, or recommended improvements to: jamesdetrick@comcast.net. ---- “Jim Detrick” -- www.facebook.com, -- www.twitter.com, -- 707-536-3272 Thursday, February 14, 2013

How we know the age of the Universe?

----------------------- # 1563 - How Old is the Universe
-

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- How old am I?
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- Well the living part is 72 years old.
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- How old is the non-living part, the lineage of homo-sapiens?
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- That part goes back 2,000,000 years of evolution.
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- How old is my DNA that was controlling all this evolution?
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- That part goes back 3,500,000,000 years. Shortly after Earth’s formation life started out as single living cells. These microbes outnumber your living cells on your body as we speak.-
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- How old are the elements that make up the proteins and blood and tissue in my body?
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- Now we are getting to near the age of the Universe. 13,700,000,000 years. All the heavier elements above hydrogen, helium, and lithium were formed in the first supernovae explosions. Our Sun will live for 10,000,000,000 years. It is a 3^rd generation star and contains many of these heavier elements. The first generation stars were very massive and only lived a few million years. Their first supernovae explosions spread heavier elements in gas and particles that were used to make the later generation stars. -
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- The iron in your blood, the calcium in your bones, the carbon in your tissue could be 13,700,000,000 years old and still kicking.
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- How do we know how old the Universe is?
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- There are 4 ways: radioactive dating, color of the stars, how fast the galaxies are moving away from us, and, the sound waves in the Cosmic Microwave Background.
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- Radioactive dating: The heaviest elements have too many protons and too many neutrons to remain stable. The heaviest elements decay into lighter elements. Since there are a lot of protons and neutrons in these samples of elements, the law of large numbers, and statistics can predict with great accuracy the decay rates.
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---------- Carbon-14 -------------- Nitrogen-14 ------------ 5,730 year half-life -------
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---------- Aluminum-26 ---------- Magnesium-26 ------ 720,000 year half-life -------
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---------- Potassium-40 ----------- Argon-40 -------- 1,250,000,000 year half-life -----
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---------- Ribidium-87 ------------ Strontium-87 ----- 48,800,000,000 year half-life -----
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---------- Thorium-232 ------------ Uranium-232 ---- 14,050,000,000 year half-life ---
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---------- Uranium-238 ------------ Lead-206 ------- 4,468,000,000 year half-life -----
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- These are radioactive elements because when a neutron decays into a proton it emit’s a high energy Gamma Ray, or , a high energy particle, helium nuclei.
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- A “ half life” is a set amount of time that half the nuclei of each radioisotope decays into a lighter product. By measuring the ratio of the lighter product to the amount of the original isotope we can calculate the age of the material.
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- You have discovered some bones of you ancestors. If half the carbon-14 has decayed into nitrogen-14 then the bones are 5,730 years old. If one-quarter of the carbon-14 remains the bones are 11,460 years old.
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- The oldest rocks found on Earth are 3,800,000,000 years old. Meteorites found on the surface of the Earth have been dated at 4,567,000,000 years old. This tells us the age of our Solar System, the age of our Sun. We can use the same calculation to find the ages of other stars.
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- The ratio of Potassium-40 to Argon-40 + Potassium-40 is 0.85 / 0.85 + 9.15. The half-live of Potassiu-40 is 1.25 billion years.
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---------------------- 0.85 / 10 = (½ )^ Time / half-life
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-------------------- 0.085 = (½ )^ Time / 1.25
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-------------------Time = 1.25 * log 0.085 / log ½
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------------------ Time = 1.25 * (-1.07) / 20.301
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-------------------- Time = 4.45 billion years.
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- The meteorite is 4,450,000,000 years old.
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- Astronomers use spectroscopy to identify the elements in the star. They find that a particular star has 14.3% of its Uranium-238 left. The rest as already decayed to Uranium-235. The half-life of U238 is 4,468,000,000 years. The decay rate is exponential because as decays occur there are fewer U238 atoms to decay. When we reach the half-life, 50% of time, the percentage of U238 atoms remaining is 69.3%
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-------------------- U238 / U238 + U235 = e^-0.69 * (Time / half-life)
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------------------- 0.143 = e^-0.69 * (Time / 4.47)
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------------------ log 0.143 = -0.69 * (Time / 4.47)
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------------------ - 1.95 = - 0.154 * Time
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---------------- Time = 12.66 billion years.
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- The star is 12,660,000,000 years old. The Universe was only 8% of its current age.
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- The color of stars: When a gas heats up it emit’s a color characteristic of the element. Absorption lines in the spectrum of this color are unique to each of the 92 natural elements. The absorption lines represent the energy gaps between shells of electrons. Each element has unique energy gaps and therefore unique absorption lines.
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- When the Universe was born in the Big Bang only 3 elements were created, hydrogen, helium, and lithium. All of the 1^st generation stars made from these elements have exploded as supernovae. They were large, massive stars that lived only a few million years. Their explosions created the heavier elements. The 2^nd generation stars were made of this mix of heavier elements. Then 3^rd generation stars had even a greater mix of heavier elements. Our Sun is a 3^rd generation star.
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- In 2007 a star was dated to be 13,200,000,000 years old. Therefore, our Universe must be older than that. Astronomers used Thorium-232 dating ( 90 protons, 142 neutrons and a half-life of 12,500,000,000 years.)
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- Globular Clusters of stars are all born at the same time. They are all different sizes and have all different lifetimes. The smaller stars live the longest. The oldest star in a Milky Way globular cluster is no more massive than 70% that of our Sun. That means the cluster must by 11 to 14 billion years old.
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- The Universe Expansion: Edwin Hubble discovered that distant galaxies were traveling away from us faster the further their distance. He calculated the expansion to be 500 kilometers/second per Mega parsec. 1 Mega parsec is 3.26 lightyears distance. His answer was too high.
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- Today the measurement is 74.3 km/sec/Mega parsec . This equates to 47,000 miles per hour per million lightyears distance. 13 miles per second. Running this expansion rate backwards by taking the reciprocal of the Hubble rate of expansion.
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--------------- 1 / Ho = 1 / 74.3 km/sec / 3.262 *10^6 LY
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-------------- 1 / 22.8 km/sec
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---------------- speed of light 3*10^5 km/sec / 22.8 *10^10^-6
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----------------- 13.2 billion years. Takes us back to the Big Bang.
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- Cosmic Microwave Background: The most accurate measurement of the age of the Universe comes from the sound waves in the CMB. 375,000 years after the Big Bang the sound waves, or density waves, were frozen in the fluctuations we see today. Since then temperatures have cooled from 3,000 Kelvin to 2.725 Kelvin. From Infrared radiation to Microwave radiation. The 2.725 Kelvin temperature is the temperature of space in all directions. Uniform radiation, except at 1/1000 degree you can find these fluctuations.
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- Astronomers measure the sizes of these density waves across the sky. Their wavelength is represented by the arc seconds degrees separating the wave peaks and valleys. The is the sound wave oscillation period from the least dense to the most dense pressures. This fundamental wavelength represents 480 million lightyears distance. It is the wavelength of the farthest distance a pressure wave could reach in the finite time of 375,000 years before it became frozen in the CMB.
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- The fundamental and harmonic wavelengths in the CMB allow astronomers to calculate the age of the Universe to be 13,770,000,000 years old. It allowed the composition of matter’s gravity attraction and Dark Energy vacuum expansion to be calculated: 25% matter and 75% Dark Energy. It allowed the geometry of the Universe to be defined as “flat” as opposed to be a sphere, or being a saddle shape. It calculated the critical mass to be 10^-29 grams per cubic centimeter. That is the mass needed to cause the balance between the gravity forces of attraction to the expansion forces of Dark Energy.
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- The Planck satellite launched in May, 2009 will repeat these measurement of the CMB with 4 times greater resolution. Who would have thought that the age of the Universe would be found in the harmonics of sound waves. An announcement will be made shortly, stay tuned.
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(1) Radioactive dating see reviews #1278 and # 1515
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(2) CMB reviews #757, #823, #1305
　
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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 upon request. Some reviews are at http://jdetrick.blogspot.com Please send feedback, corrections, or recommended improvements to: jamesdetrick@comcast.net. ---- “Jim Detrick” -- www.facebook.com, -- www.twitter.com, -- 707-536-3272 Sunday, February 3, 2013