JimsAstronomy: May 2020

Sunday, May 31, 2020

LAGRANGE POINTS - in space travel?

- 2750 - LAGRANGE POINTS - in space travel? - What are Lagrange Points and how are the used in space travel? The Lagrange Points are where two sources of gravity meet and cancel each other out to create a zero gravity environment in space. This Review uses the Earth and the Moon as the two sources of gravity.
-

-
------------ 2750 - LAGRANGE POINTS - in space travel?
-
- Let’s say you want to put a 4,000 pound spacecraft on the Moon. How much would it cost? The going rate is $250,000 per pound. That brings the cost to $1,000,000,000. It takes only 3 days to travel to the Moon, but, $1 billion is pretty expensive for the trip. It is 250,000 miles to get there traveling at 7,200 miles per hour it takes 35 hours. That is only 1 ½ days. Right, but the trip does not go in a straight line.
-
- The trip starts with a launch into Earth orbit. Then, to escape this orbit and escape the Earth’s gravity rockets are fired to reach the speed of 7,200 miles per hour ( 2 miles per second).
-
- When the spacecraft gets to the Moon the process has to be reversed. The ship turns itself around and fires its rockets to slow down and get captured by the Moon’s gravity. This slow-down maneuver alone costs $130,000,000 in fuel.
-
- The whole mission is simple to calculate for astronomers. It can be done on a pocket calculator. And, it has worked successfully several times. The disadvantage, it is expensive. How can we make the trip and not cost so much?
-
- Using more supplicated mathematics it should be possible to define a trajectory that continually surfs the gravitational flows between the Earth and the Moon. If we get the right trajectory we should be able to coast into orbit around the Moon. Theoretically there should be no need to even use reverse thrusters to get into Moon orbit.
-
- After the launch into Earth orbit the spaceship slowly spirals out using a low continuous thrust. The spiral orbit continues out until it reaches a gravitational tug from the Moon. Once there the Moon will pull the ship into orbit.
-
- The real trick in the calculation is when the gravity of Earth and the gravity of the Moon cancel out. Mathematically this calculation becomes one of “chaos theory” for a “3-body problem“. ( Earth, Moon, and spacecraft). The slightest nudge in any direction can amplify the trajectory tremendously.
-
- In addition to the math getting difficult the time it takes extends to a 2 year trip. Compared to a 3 day trip this cheap trip may be too cheap. NASA said we like the math, thanks, but no thanks.
-
- Then a Japan launch of an unmanned spacecraft ran awry. One vehicle was a relay station for the trip to the Moon. The other craft was supposed to fly to the Moon, but, it lost radio contact and left the mission. The relay station had very little fuel. NASA needed a way to salvage the mission.
-
- The mathematics brought in another character, the Sun. Working backwards from the Moon orbit they bound a trajectory using the Sun’s gravity that was only 1 million miles away from the relay station.
-
- Now, the math had a “4-body problem” to solve with 3 boundaries of chaos theory. The idea still worked. The Spacecraft slowly worked its way out to the Earth-Sun boundary. Then, with a little bit of fuel nudged the rocket toward the Earth-Moon Boundary. Another little nudge and off to the Moon. The Japanese spacecraft “Hiten” safely arrived at Moon October 2, 1991 after a 5 month trajectory. It was all done with the math and minimum use of fuel.
-
- Now with this astonishing success, astronomers are looking at navigating the entire Solar System by surfing on the gravitational boundaries between the planets. It takes a lot of math but the trade off can be worth the effort in making the mission possible.
-
- The gravity boundaries are called “ Lagrangian points”, Joseph-Louis Lagrange (1736 - 1813). Like trash collecting in the currents meeting in the Pacific Ocean, there are asteroids and space junk collecting in the gravity boundaries.
-
- They are called “Trojan asteroids” and they follow the planets around in their orbits. The Sun-Earth boundary is 930,000 miles from Earth. The Earth-Moon boundary is 38,200 miles from the Moon.
-
- That is how the math can make new space missions possible minimizing the fuel needed to be carried.
-
- May 31, 2020 1143 2750
----------------------------------------------------------------------------------------
----- Comments appreciated and Pass it on to whomever is interested. ----
--- Some reviews are at: -------------- http://jdetrick.blogspot.com -----
-- email feedback, corrections, request for copies or Index of all reviews
--- to: ------ jamesdetrick@comcast.net ------ “Jim Detrick” -----------
- https://plus.google.com/u/0/ -- www.facebook.com -- www.twitter.com
--------------------- Sunday, May 31, 2020 -------------------------
-----------------------------------------------------------------------------------------

Friday, May 29, 2020

GRAVITY - does it travel at the speed of light?

- 2749 - GRAVITY - does it travel at the speed of light? The theory of special relativity showed that particles of light, photons, travel through a vacuum at a constant pace of 670,616,629 miles per hour. All across space, from black holes to our near-Earth environment, “particles” are, in fact, being accelerated to incredible speeds, some even reaching 99.9% the speed of light. Is gravity traveling at light speeds too?
-

-
------------ 2749 - GRAVITY - does it travel at the speed of light?
-
- One hundred years ago today, on May 29, 1919, measurements of a solar eclipse offered verification for Einstein's theory of general relativity. Even before that, Einstein had developed the theory of special relativity, which revolutionized the way we understand light. Light is a particle / wave that we call a “photon.
-
- Studying cosmic rays which are hydrogen atom nuclei and superfast, or relativistic, “particles” can help protect missions exploring the solar system, traveling to the Moon, and they can teach us more about our galactic neighborhood. A well-aimed near-light-speed particle can trip onboard electronics and too many at once could have negative radiation effects on space-faring astronauts as they travel to the Moon, or beyond.
-
- There are three ways that this particle acceleration happens. One is with “electromagnetic fields’. Most of the processes that accelerate particles to relativistic speeds work with electromagnetic fields. The two components, electric and magnetic fields, like two sides of the same coin, work together to accelerate particles at relativistic speeds throughout the universe.
-
- Electric and magnetic fields can add and remove energy from particles, changing their speeds. Electromagnetic fields accelerate charged particles because the particles feel a force in an electromagnetic field that pushes them along, similar to how gravity pulls at objects with mass. In the right conditions, electromagnetic fields can accelerate particles at near-light-speed.
-
- On Earth, electric fields are often specifically harnessed on smaller scales to speed up particles in laboratories. Particle accelerators, like the Large Hadron Collider and Fermilab, use pulsed electromagnetic fields to accelerate charged particles up to 99.99999896% the speed of light.
-
- At light speeds, the particles can be smashed together to produce collisions with immense amounts of energy. This allows scientists to look for elementary particles and understand what the universe was like in the very first fractions of a second after the Big Bang.

- Another way particles are accelerated is with “magnetic explosions”. Magnetic fields are everywhere in space, encircling Earth and spanning the solar system. They even guide charged particles moving through space, which spiral around the fields.
-
- When these magnetic fields run into each other, they can become tangled. When the tension between the tangled crossed lines becomes too great, the lines explosively snap and realign in a process known as magnetic reconnection.
-
- The rapid change in a region's magnetic field creates electric fields, which causes all the attendant charged particles to be flung away at high speeds. Scientists suspect magnetic reconnection is one way that particles, for example, the solar wind, which is the constant stream of charged particles from the sun, is accelerated to relativistic speeds.
-
- Those speedy particles also create a variety of side-effects near planets. Magnetic reconnection occurs close to us at points where the sun's magnetic field pushes against Earth's magnetosphere, the Earth’s protective magnetic environment.
-
- When magnetic reconnection occurs on the side of Earth facing away from the sun, the particles can be hurled into Earth's upper atmosphere where they spark the auroras.
-
- Magnetic reconnection is also thought to be responsible around other planets like Jupiter and Saturn, though in slightly different ways.
-
- NASA's spacecraft have been designed and built to focus on understanding all aspects of magnetic reconnection. Using four identical spacecraft, the mission flies around Earth to catch magnetic reconnection in action. The results of the analyzed data can help scientists understand particle acceleration at relativistic speeds around Earth and across the universe.
-
- A third way particles are accelerated is with Wave-Particle Interactions. When electromagnetic waves collide, their fields can become compressed. Charged particles bouncing back and forth between the waves can gain energy similar to a ball bouncing between two merging walls.
-
- These types of interactions are constantly occurring in near-Earth space and are responsible for accelerating particles to speeds that can damage electronics on spacecraft and satellites in space. NASA missions, like the Van Allen Probes, help scientists understand wave-particle interactions.
-
- Wave-particle interactions are also thought to be responsible for accelerating some cosmic rays that originate outside our solar system. After a supernova explosion, a hot, dense shell of compressed gas called a blast wave is ejected away from the stellar core.
-
- Filled with magnetic fields and charged particles, wave-particle interactions in these bubbles can launch high-energy cosmic rays at 99.6% the speed of light. Wave-particle interactions may also be partially responsible for accelerating the solar wind and cosmic rays from the sun.
-
- Gravity itself travels at the speed of light? Astronomers have measured this when
two neutron stars collided and the resulting gravitational wave spread at the speed of light. The neutron stars which are dead cores of two stars collided 130 million years ago in a galaxy somewhat far away.
-
- The collision was so extreme that it caused a wrinkle in space-time, called a gravitational wave. That gravitational wave and the light from the stellar explosion traveled together across the cosmos. They arrived at Earth simultaneously at 6:41 a.m. Eastern on August 17, 2019.
-
- The event prompted worldwide headlines. Astronomers had waited a generation for this moment. But it was also the first-ever direct confirmation that gravity travels at the speed of light.
-
- We all know light obeys this speed limit, roughly 186,000 miles per second. Nothing travels faster. But why should gravity travel at the same speed? That question requires an understanding of Albert Einstein’s general relativity, the theory of gravity, which is the same theory that predicted gravitational waves a century ago.
-
- Einstein overthrew Isaac Newton’s idea of “absolute time.” Newton thought time marched onward everywhere at an identical pace, regardless of how we mortals perceived it. It was unflinching. By that line of thinking, one second on Earth is one second near a black hole, which he didn’t know existed.
-
- Newton also thought gravity acted instantaneously. Distance didn’t matter. But then Einstein showed that time is “relative“. It changes with speed and in the presence of gravity. One of the ramifications of that is that you can’t have simultaneous actions at a distance. So information of any kind has a finite speed, whether it’s a photon, the light-carrying particle, or a graviton, which carries the force of gravity.
-
- “In relativity, there is a ‘speed of information’, the maximum speed that you can send information from one point to another”.
-
- In electromagnetism, when you shake an electron, it creates a change in the electric field that spreads out at the speed of light. Gravity works the same way. Shake a mass and the change in the gravitational field, the gravitational wave, propagates at that same speed.
-
- So the fact that the speed of gravitational waves is equal to the speed of electromagnetic waves is simply because they both travel at the speed of information.
-
- There’s an easy way to picture this, too. Imagine the sun vanished right now. Earth wouldn’t just drift into space instantly. After eight minutes, Earth would go dark and simultaneously push off in a straight line.
-
- Let’s hope this doesn’t happen.
-
---------------------------------------- More reviews on the subject:
-
- 2656 - GRAVITY - in supernovae explosions. Is the force of gravity instantaneous across the Universe? Or does gravity have a speed limit to how fast the force can travel.? This is not as simple a question as it seems on the surface.
-
- 2628 - GRAVITY WAVES - from supernovae explosions? Is the speed of gravity instantaneous, or is there a speed limit on how fast the force of gravity can travel. This is not as simple a question. After all, we know how fast light travels, and if the Sun were to suddenly wink out of existence, we’d still receive light from it for just over 8 minutes after it disappeared!
-
- 2438 - GRAVITY - traveling at the speed of light? If the Sun went dark instantaneously we would not know it until 8 minutes later., when the last bit of light reached us. The same delay would occur with gravity. If the Sun disappeared altogether the Earth would continue to orbit for another 8 minutes before it would shoot off into space in a straight line.
-
- 2356 - If a gravity wave comes through the detector it would sound like a “chirp”. This chirp could be a very old gravity wave. Today the Universe is 13.7 billion years old. Light, or photon, did not appear until 100,000 years after the Big Bang. But gravity started at the first instant, 10^-43 seconds after the beginning. Studying gravity waves will allow us to peer far back in to the beginning of time and space.
-
- 2176 - The Gravity of the Details. Maybe it is time for someone to discover some new physics for gravity. Those gnawing details need to be reconciled. Facts are messing with our theories. Dark Matter and Pioneer anomalies could disappear with new equations.
-
- 2175 - Why is gravity so small?. You would not have come up with this question
naturally because we thing of gravity is being big. A big powerful force. Just try to lift 100 pounds. But, you have to realize the other part of gravity is the mass of the Earth and it is very, very big, 13,200,000,000,000,000,000,000,000 pounds. Yet, a small magnet will pick up a paper clip that the entire Earth can not hold on to.
-
- 2174 - Gravity - What is it Really? - Gravity is the force that causes masses to attract each other. Or, maybe, gravity is not a force. Maybe gravity is the least energy way for mass to travel through spacetime. Mass tells spacetime how to bend. Spacetime tells mass how to move. These two different explanations appear to be totally unrelated in explaining the same thing, gravity.
-
- 2170 - Gravitational waves are the next way to measure the expansion rate of the universe. The two other methods being used to measure expansion are Supernovae Type1a and Acoustic waves in the cosmic microwave background. Their answers differ by 9%. This is not even close enough for government work, let alone astronomy.
-
- 2127 - Einstein's Ring. How can empty space bend light? How can time slow down or speed up? Is it not the same everywhere in the universe? If general relativity holds true on the scale of entire galaxies then 95% of the universe is made up of invisible substances called dark matter and dark energy.
-
- 2089 - In 1687 when Sir Isaac Newton was 45 years old he detailed the laws of gravity in a simple equation. F = G * M1*M2 /r^2. In 1850 Jean Joseph LeVenier noticed that when using Newton’s equations for gravity to calculate the orbit of Mercury results were a little off. 230 years after Newton’s equations, Albert Einstein, in 1916, came up with a more detailed equation for gravity that included the bending of space and time in the presence of mass. Science is just not satisfied for this accuracy in their equations. Either the equations are off making the math off, or, the astronomers' measurements are in error.
-
- May 29, 2020 2749
----------------------------------------------------------------------------------------
----- Comments appreciated and Pass it on to whomever is interested. ----
--- Some reviews are at: -------------- http://jdetrick.blogspot.com -----
-- email feedback, corrections, request for copies or Index of all reviews
--- to: ------ jamesdetrick@comcast.net ------ “Jim Detrick” -----------
- https://plus.google.com/u/0/ -- www.facebook.com -- www.twitter.com
--------------------- Friday, May 29, 2020 -------------------------
-----------------------------------------------------------------------------------------

MATTER - missing matter in the Universe?

- 2748 - MATTER - missing matter in the Universe? Remember matter and energy are two forms of the same thing. Energy = matter * (speed of light)^2. ‘Ordinary matter’ is everything that is known in “our world“. It is all that we see, feel, and know in our Universe. Well, that was until this decade when science started proposing that there is a lot more that we can not see and to this day remains unknown.

-
------------ 2748 - MATTER - missing matter in the Universe?
-
- In the late 1990s, scientists made a prediction about how much “ordinary matter” there should be in the universe. About 5%, they estimated, should be regular stuff with the rest a mixture of dark matter and dark energy. But when cosmologists counted up everything they could see or measure at the time, they came up short. By a lot.
-
- The sum of all the ordinary matter that cosmologists measured only added up to about half of the 5% what was supposed to be in the universe. This is known as the “missing baryon problem” and for over 20 years, scientists have looked hard for this matter without success. Baryons is just another name for Ordinary Matter.
-
- Baryon is a classification for types of particles that encompasses protons and neutrons, the building blocks of all the ordinary matter in the universe. Everything on the periodic table and pretty much anything that you think of is made of baryons.
-
- Since the late 1970s, cosmologists have suspected that dark matter to be an unknown type of matter that must exist to explain the gravitational patterns in space. It makes up most of the matter of the universe with the rest being baryonic matter, but they didn’t know the exact ratios. Gravity is the force that depends on mass, or matter, and decays as the square of distance of separation.
-
- In 1997, scientists used the ratio of heavy hydrogen nuclei, that is hydrogen with an extra neutron, to normal hydrogen to estimate that baryons should make up about 5% of the mass-energy budget of the universe.
-
- Other cosmologists reported that a direct measure of baryons in our present universe by determining through a census of stars, galaxies, and the gas within and around them added up to only half of the predicted 5%, or 2.5% being ‘Ordinary Matter”.
-
- This sparked the “missing baryon problem“. Provided the law of nature held that matter can be neither created nor destroyed, there were two possible explanations: Either the matter didn’t exist and the math was wrong, or, the matter was out there hiding somewhere.
-
- In 2001, astronomers confirmed the initial prediction of baryons making up 5% of the universe by looking at tiny temperature fluctuations in the universe’s cosmic microwave background which is essentially the leftover radiation from the Big Bang. With two separate confirmations of this number, the math had to be right.
-
- In 2007, astronomers made the discovery of a cosmological phenomenon known as a fast radio burst (FRB). FRBs are extremely brief, highly energetic pulses of radio emissions. Cosmologists and astronomers still don’t know what creates them, but they seem to come from galaxies far away.
-
- As these bursts of radiation traverse the universe and pass through gasses and undergo something called ‘dispersion“.
-
- The initial mysterious cause of these FRBs lasts for less a thousandth of a second and all the wavelengths start out in a tight clump. To be near the spot where an FRB was produced, all the wavelengths would hit simultaneously.
-
- But when radio waves pass through matter, they are briefly slowed down. The longer the wavelength, the more a radio wave interacts with the matter. Think of it like wind resistance.
-
- This “wind resistance” effect on radio waves is incredibly small, but space is big. By the time an FRB has traveled millions or billions of light-years to reach Earth, dispersion has slowed the longer wavelengths so much that they arrive nearly a second later than the shorter wavelengths, or higher frequencies.
-
- Therein lay the potential of FRBs to weigh the universe’s baryons. By measuring the spread of different wavelengths within one FRB, we could calculate exactly how much matter, how many baryons, the radio waves passed through on their way to Earth.
-
- To precisely measure the baryon “density“, astronomers need to know where in the sky an FRB came from. If we knew the source galaxy, we would know how far the radio waves traveled. With that and the amount of dispersion they experienced, they could calculate how much matter they passed through on the way to Earth?
-
- The first FRB astronomers detected came from a galaxy that is about 4 billion light-years away from Earth. Astronomers were able to measure the dispersion from an FRB and knew where it came from.
-
- By July 2019, astronomers had detected five more events which was enough to perform the first search for the missing matter. Using the dispersion measures of these six FRBs, they were able to make a rough calculation of how much matter the radio waves passed through before reaching earth.
-
- The data predicted the same 5% estimate. The excellent correspondence confirms the detection of all the missing matter. Astronomers were able to estimate the amount of baryons, but with only six data points, you can’t yet build a comprehensive map of the missing baryons.
-
- The missing matter is believed to be part of a vast filamentary network of gas that connects galaxies termed “the cosmic web,” but if astronomers had about 100 fast radio bursts they could start building an accurate map of this web.
-
- Understanding fast radio bursts will help us learn more about parallel universes, why time seems to move in one direction only, and why we don’t understand chaos. No matter how astronomers crunch the numbers, the universe simply doesn't add up.
-
- One example is what is dark matter? Evidently, about 84 percent of the matter in the universe does not absorb or emit light. "Dark matter," as it is called, cannot be seen directly, and it hasn't yet been detected by indirect means.
-
- Dark matter's existence and properties are inferred from its gravitational effects on visible matter, radiation and the structure of the universe. This shadowy substance is thought to pervade the outskirts of galaxies, and may be composed of "weakly interacting massive particles," or WIMPs.
-
- Worldwide, there are several detectors on the lookout for WIMPs, but so far, not one has been found. One recent study suggests dark mater might form long, fine-grained streams throughout the universe, and that such streams might radiate out from Earth like hairs.
-
- Matter and energy are two forms of the same thing. Another example of unknowns is what is Dark Energy? What is mysterious energy that even though gravity is pulling inward on space-time this energy keeps expanding outward faster and faster. To account for this, astronomers have proposed an invisible agent that counteracts gravity by pushing space-time apart.
-
- In the most widely accepted model of dark energy, it is a "cosmological constant": an inherent property of space itself, which has "negative pressure" driving space apart. As space expands, more new space is created, and with it, more dark energy.
-
- Based on the observed rate of expansion, scientists know that the sum of all the dark energy must make up more than 70 percent of the total contents of the universe. But no one knows how to look for it. The best researchers have been able to do in recent years is narrow in a bit on where dark energy might be hiding.
-
- Then astronomers are left with another mystery. Why is there more matter than antimatter? The question of why there is so much more matter than its oppositely-charged and oppositely-spinning twin, antimatter, is actually a question of why anything exists at all.
-
- One assumes the universe would treat matter and antimatter symmetrically, and thus that, at the moment of the Big Bang, equal amounts of matter and antimatter should have been produced. But if that had happened, there would have been a total annihilation of both. Protons would have canceled with antiprotons, electrons with anti-electrons (positrons), neutrons with antineutrons, and so on, leaving behind a sea of photons in a matterless expanse.
-
- For some reason, there was excess matter that didn't get annihilated, and here we are. I can’t explain this either. For this, there is no accepted explanation. The most detailed test to date of the differences between matter and antimatter confirm they are mirror images of each other, providing exactly zero new paths toward understanding the mystery of why matter is far more common.
-
- The universe experiences four fundamental forces: electromagnetism, the strong nuclear force, the weak interaction (also known as the weak nuclear force) and gravity. To date, physicists know that if you turn up the energy enough, inside a particle accelerator, three of those forces "unify" and become a single force.
-
- Physicists have run particle accelerators and unified the electromagnetic force and weak interactions, and at these higher energies, the same thing should happen with the strong nuclear force and, eventually, with gravity too.
-
- But even though theories say that should happen, nature doesn't always oblige. So far, no particle accelerator has reached energies high enough to unify the strong force with electromagnetism and the weak interaction. Including gravity would mean yet more energy.
-
- It isn't clear whether scientists could even build one that powerful; the Large Hadron Collider, can send particles crashing into each other with energies in the trillions of electron volts ( 14 tera-electron volts, or TeV). To reach grand unification energies, particles would need at least a trillion times as much, so physicists are left to hunt for indirect evidence of such theories.
-
- Besides the issue of energies, Grand Unified Theories (GUTs) still have some problems because they predict other observations that so far haven't panned out. There are several GUTs that say protons, over immense spans of time (on the order of 10^36 years), should turn into other particles. This has never been observed, so either protons last much longer than anyone thought or they really are stable forever.
-
- Another prediction of some types of this theory is the existence of magnetic monopoles which are isolated "north" and "south" poles of a magnet. Nobody has seen one of those, either. It's possible we just don't have a powerful enough particle accelerator. Or, physicists could be wrong about how the universe works.
-
- This all leaves young science students with plenty to work on. So much we do not yet understand.
-
------------------------------------ other Reviews available:
-
- 2342 - The Waves of Matter. If all matter is waves then this could explain how matter interacts with all other matter in the Universe. Maybe some day we will understand how gravity is produced by matter. If all matter in the Universe is interconnected how big should the Universe be?
-
- 2135 - MATTER - Atoms at Absolute Zero. There are at least six forms of matter. Everyone is familiar with three of them: gas, liquid, solid. If we keep cooling and adjusting temperatures and pressures on matter we can come across three more forms of matter: plasma, boson condensation, fermionic condensation. Learn about the strange properties matter acquires as temperatures approach -273 C, or 0 degrees Kelvin.
-
- 2136 - Mayan Calendar. The ancient Maya were capable astronomers and their predictions must not be taken lightly. They had precise understanding of the Sun’s path throughout the year. They knew that December 21 was the shortest day of the year, winter season begins. They knew the phases of the Moon. They knew the movements of the 4 visible planets. The ancient Maya calendar predicts the end of the world on December 21.
-
- May 28, 2020 2748
----------------------------------------------------------------------------------------
----- Comments appreciated and Pass it on to whomever is interested. ----
--- Some reviews are at: -------------- http://jdetrick.blogspot.com -----
-- email feedback, corrections, request for copies or Index of all reviews
--- to: ------ jamesdetrick@comcast.net ------ “Jim Detrick” -----------
- https://plus.google.com/u/0/ -- www.facebook.com -- www.twitter.com
--------------------- Friday, May 29, 2020 -------------------------
-----------------------------------------------------------------------------------------

Tuesday, May 26, 2020

FORCE = mass * acceleration?

- 2747 - FORCE = mass * acceleration? - This relation was discovered by Isaac Newton in 1687 in his studies to understand the force of gravity. Newton concluded that the force of gravity was the same everywhere in the Universe. It was “universal“.

-
------------ 2747 - FORCE = mass * acceleration?
-
----------------------- F = m*a.
-
- Newton derived an equation for this universal force of gravity between two masses as being proportional to the product of the two masses and inversely proportional to the square of the distance between them.
-
------------------------ F = G* m*M / r^2
-
-------------------------- G = the Universal Constant of Gravity * m*M = the product of the two masses / r ^2 = the radius, or, the distance between the centers of the two masses.
-
- That the Force is inversely proportional to the square of the distance makes sense because the force spreads out like an expanding sphere. The area of the sphere grows as 4*pi*r^2. Therefore the intensity of the force is spread out, or decreases, in proportion to r^2.
-
- G is determined experimentally. It is derived from the above Newton formula when the two masses are known, the distance between their centers are known, and the force of gravity is measured.
-
------------------- G is then calculated. G = F*r^2/m*M
-
-------------------- G = 6.67259 * 10^-11 meters^3 / kilogram * seconds^2
-
--------------------------------------- FORCE:
-
- But, we started out with Force = m*a. So, the Force of gravity = m*a , and , = G*m*M / r^2. Where m is your mass, for example, and M is the mass of the Earth. On the Earth surface r = the radius of the Earth. The mass, m, your mass, cancels out.
-
- So, the force of gravity is the same for all bodies on the surface of the Earth. We are left with the acceleration of gravity = G*M / r^2. Substituting into this formula we calculate the acceleration of gravity to be 9.8 meters/second^2.
-
-
------------------------- g = G*M / r^2 = 6.67259*10^-11 m^3/kg*sec^2 * 5.9742*10^24 kg / (6.378*10^6m)^2. g = 9.8 m/sec^2.
-
- g = approximately 10 meters per second per second, or 32 feet per second per second. So the acceleration of gravity is the same for all objects in free fall. With no air resistance a feather and a hammer would fall to Earth at exactly the same rate.
-
- If you free fall from an airplane after one second you have dropped 5 meters and reach a velocity of 10 meters per second (22 miles per hour). In two seconds you will have dropped 15 meters and have a velocity of 20 meters per second (45 mph). After 3 seconds you have fallen 25 meters and have a velocity of 30 meters per second(67 mph). After 4 seconds, 35 meters and 40 meters per second (89 mph). After 5 seconds, 45 meters and 50 meters per second 112 mph). After 6 seconds you are going 134 mph.
-
- Actually air resistance will normally slow a falling body down to 120 mph maximum. Of course, you can stream line yourself and put your body in a bullet shape facing straight down and reach 200 mph, but a safer process might be to open your parachute and get more air resistance, not less.
-
- Weight is often confused with mass. Actually, Weight is the force of gravity. Weight is mass * 10 meters / second^2. If you go to a different elevation, increasing your distance from the center of the Earth, your weight will change, decrease , but your mass will remain the same.
-
- A Mass traveling at a constant velocity requires no Force. Constant velocity, including zero velocity (rest mass), is the natural state of all things. Any object will move at a constant velocity in a straight line forever with no force ever applied.
-
- To change a velocity requires a force. And a change in velocity is called acceleration, a = dv / dt. Velocity is a change in distance over a change in time, v = dx / dt.
-
- It is all relative because to record a change you must compare a beginning distance relative to an ending distance, or a start time relative to a stop time in order to record a time interval, or, change in time. Distance and length are measures of space. So, velocity is really a ratio of space and time, dx / dt.

- F = m*a gets us to the basics of physics. What is space, what is time, what is mass, what is force? These fundamental concepts have had centuries of study but we really do not fully understand them today. Sorry.
-
- It takes a force to change the velocity of a mass. Therefore, we define force as a change in velocity, an acceleration of a mass, F = m*a. A bigger mass requires a bigger force to accelerate it. A bigger force is required to accelerate a mass faster.
-
- Force is a vector quantity. It has both magnitude and direction. The direction is the direction of acceleration, which is also a vector quantity. Force is the product of mass and the rate of change of the rate of change of space with respect to time.
-
- Rate of Change is the same as the slope of the distance curve versus time, or the first derivative, velocity = dx / dt. The rate of change of the rate of change is the slope of the velocity curve plotted versus time, or the second derivative, acceleration = d^2 x / dt^2.
-
------------------- Mass times velocity is momentum, m*v = momentum.
-
- Momentum is the same as inertia. Force is the rate of change of momentum,
F = d(mv) / dt. If a force moves 1 kilogram mass increasing its velocity by 1 meter/second in one second then it is defined as a force of 1 Newton. It just becomes easier to say a force of Newtons, rather that a force of kilograms*meters/second^2. But, remember these names are just for convenience the fundamentals are still mass*space / time.
-
------------------------- Energy is a force acting over a distance. E = F*dx.
-
- Energy = kilograms*meters^2/seconds^2, or Joules. Kinetic Energy = ½ m*v^2 One Joule of energy is a force of 1 kilogram increasing velocity 1 meter/second in 1 second over a distance of 1 meter.
-
------------------------ Work is the amount of change in Energy. It is a change in force * distance and has the same units as Energy, kilograms*meters^2/seconds^2.
-
- The amount of Work done is the amount of change in Energy levels over time. Work, Torque, Heat Flow are all changes in Energy measured in Joules, which is kilograms* meters^2/seconds^2.
-
----------------------- Temperature for Heat Flow is converted into Energy using Boltzmann’s constant, 1.38*10^-23 Joules/Kelvin.
-
- Power is the rate of doing work, or the rate of change of Energy, force * distance / time, kilograms*meters^2/seconds^3. Power is expressed in Watts, which is work done in 1 second. 1 Watt = 1 Joule /second.
-
- Remember, any time we say “the rate of change“, that is the same mathematically as taking “the derivative“. It is the slope of the curve of the parameter that is changing, in this case changing versus time.
-
----------------------------- MASS:
-
- Ok, we are getting carried away trying to define what a FORCE is. We can say it is a push or pull that accelerates a mass, but, what is a mass?
-
- Mass implies a measure of the “quantity of matter“. It comes from the Latin word meaning lump of dough, or bread. In the Catholic Church it is the Eucharistic mass that is the body of Christ. Somehow it also became the word for inertia; it takes a force to get something moving; if it is moving and has some momentum it takes an opposite force to slow it down or to stop it.
-
- Mass gets defined from three different perspectives: gravity, inertia, and energy. Mass first appeared in science as “inertia mass” in the CONSERVATION OF MOMENTUM,
p = m*v and Force = the product of mass and acceleration, F = m*a.
-
- The gravity aspects of mass were discussed in the above paragraphs regarding the force of gravity, or weight, being the product of mass and the acceleration of gravity, g.
Force (weight) = m * g.
-
- In 1905 Einstein’s theory of relativity changed everyone’s concept of mass. E = m*c^2 meant that mass can change into energy and energy can change into mass. It also meant that mass of a body increase with its velocity, v.
-
----------------------- MASS = mass at rest /(1-v^2/c^2)^.5
-
- For example: If a rocket ship weighs 100 kilograms*m/sec^2 on the launch pad. Then its mass is roughly 10 kilograms with 10 meters/second^2 of acceleration of gravity. But, it the rocket is traveling at 86% the speed of light its mass is 10 kg / (1-(.86(^2).5
Mass = 20 kilograms, the mass has doubled at that velocity. Energy changes into mass.
-
- It works the other way too, mass changes into energy. If a body gives off energy as radiation its mass diminishes by Energy/c^2, Energy / 90,000,000,000,000,000 meters^2/seconds^2.
-
- Then Max Planck came along and said that Energy and Mass comes to us in packets, or quanta, as in Quantum Mechanics. Energy = Planck’s Constant * frequency = Planck’s Constant * c/wavelength. Planck’s Constant = h = 6.625 *10^-34 kilogram*meter^2/second.
-
- Note that Planck’s Constant is a unit of Energy times time, or a unit of Action . Action = m*v*dx = m * dx * dx/dt.
-
- Force = Newtons = kilograms * meters / seconds^2 = m*dx/dt^2 = dmv/dt.
Momentum = m*v = m*dx*dt.
-
- Action = Force * distance * time = Newton * meters * seconds = kilograms * meters^2/second = m*dx^2/dt
-
- Energy = Joules = Force * distance = kilogram*meters^2/seconds^2 = md^2x/dt^2.
Kinetic Energy = ½ m*dx/dt*dx/dt.
-
- Work is the change in Energy, delta E, dw = F*dx.
-
- Torque and Heat Flow are forms of Energy and have the same units.
-
- Power = watts = rate of change of Energy with time = dE/dt = kilograms * meters^2/seconds^3.
-
- Entropy = Energy / temperature = kilogram*meters^2/seconds^2*Kelvin
-
- Now, mass is thought of as being both a particle and a wave. The momentum of a particle, m*v = Planck’s constant / wavelength, h/w.
-
- Gravitational force is a function of an observer’s position as well as his velocity and acceleration, and, therefore, is a property of space-time. Distance, length, velocity, acceleration are all descriptions of space - time, and, are connected by Motion. Motion can be inferred only with reference to a second object. Motion is relative and always requires a reference.
-
---------------------- SPACE: Space is a positional quality of all objects.
-
- A space with 2 dimensions expands as the circumference of a circle proportional to the radius ( 2*pi*r). A space with 3 dimensions expands as the surface of a sphere which proportional to the radius squared (4*pi*r^2) If space were 4 dimensions the gravitational force would decrease proportional to the radius cubed ( 8*pi*r^3). Since Newton showed that gravity decreases as the radius squared then space must be 3 dimensions.
-
- From Einstein’s perspective space is viewed as sets of spatial and time relationships among objects (mass and energy). The space -time structure is based upon the propagation of light and the motion of free-falling bodies.
-
- But, free falling is not in Euclidian space it is in Riemannian space which is curved space-time and straight lines become geodesic lines, or, Great Circles on a spherical surface. Airlines travel a geodesic line between cities, the shortest distance is a great circle on the surface of the Earth.
-
- Emmy Noether a mathematician who in 1932 deduced the theorem that for every continuous Symmetry in the laws of physics there exists a LAW OF CONSERVATION. Noether’s theorem is one of the most profound theories ever deduced. It is right up there with Einstein’s Theory of Relativity.
-
- Space has Symmetry. It is Isotropic, it looks the same in all directions. As a consequence of the rotational symmetry of space the law of the CONSERVATION OF ANGULAR MONENTUM is derived.
-
- The LAW OF CONSERVATION OF LINEAR MOMENTUM is a consequence of the translational symmetry, or, homogeneity of space. Einstein used this Theorem of Symmetry for inertia which is equivalent for all states of motion to derive the Theory of Relativity.
-
- Wolfgang Pauli used Symmetry to predict the existence of the neutrino as a particle of no charge and very small mass using the CONSERVATION OF MOMENTUM. The neutrino was discovered 26 years later in 1956.
-
-------------- MASS: From Gauge Symmetry physicists have deduced that space is not empty, it contains virtual particles called Higgs Bosons that attract all matter giving it inertia and mass. This is a theory of symmetry that could explain what is mass. The Higgs particle was just recently discovered in the particle accelerator at CERN, Switzerland.
-
-------------- ENERGY: The fact that the laws of physics are invariant under all translations in time it follows the Law of CONSERVATION OF ENERGY. All forms of energy can be changed but they can never be destroyed in order to maintain this Symmetry.
-
- Doug is driving his 1000 kilogram Cobra down a level stretch of highway going 60 miles per hour (30 meters/second). He takes his foot off the acceleration and lets the Cobra coast and times how long it takes for the Cobra to slow down to 50 miles per hour (25 meters/second). It takes 10 seconds.
-
- The Kinetic Energy of the Cobra at 60 mph = ½*m*v^2 = ½*1000Kg*(30m/s)^2 = 450,000 kg*m^2/sec^2. When the Cobra slows down to 50 mph the Kinetic Energy was ½*1000kg*(25 m/s)^2 = 312,500 kg*m^2/sec^2.
-
- So, in 10 seconds the Cobra lost 137,000 joules of Energy. This amounts to 13,750 joules/second, which is the same as 13,750 watts. This is equivalent to 137 100 watt light bulbs needed to keep the car going down the highway at 60 mph. (You can try this with your car and learn how much horsepower you are consuming down the highway.)
-
- The energy is consumed but not lost. Energy is converted mostly into heat due to friction in the engine, friction in the tires, friction in the air resistance, but also in sound energy, heating the water in the radiator, etc.
-
- There are .001341 horsepower in 1 watt. So, 18 horsepower is needed to maintain the Cobra at 60 mph. The other 432 horses are used for passing.
-
- The average person consumes 2000 Calories per day. There are 4,200 Joules per Calorie so the person consumes 8,400,000 Joules of food energy every day. There are 86,400 seconds in a day.
-
- So, Joules/seconds, or watts, is 97 watts. Each person burns energy at about the same rate as a 100 watt light bulb. So, the Cobra’s energy at 60 mph, is equivalent to 18 horses or 137 people.
-
- If the horses were pulling he could probably get up to 15 mph, if the people were pushing barely 5 mph. Burning gas gets him to 60 mph, no problem, with energy to burn. At full power the Cobra is 336 kilowatts, equivalent to 3,356 100 watt light bulbs. You have to wear sunglasses in order to drive it.
-
- So, what have we learned? FORCE = MASS* SPACE/ TIME / TIME. FORCE is the space rate of change of Energy. What is Energy? Because the laws of physics are symmetrical, they do not vary with time or space.
-
- The LAWS OF CONSERVATION exist for MOMENTUM (MASS*SPACE*TIME), FOR MASS/ENERGY, FOR ELECTRIC CHARGE, OF PARITY, FOR GAUGES, FOR HIGGS FIELD, and more.
-
- ENTROPY always increases, meaning everything in motion is towards randomness. What is Time? Maybe, my next review.
-
- May 26, 2020 646 2747
----------------------------------------------------------------------------------------
----- Comments appreciated and Pass it on to whomever is interested. ----
--- Some reviews are at: -------------- http://jdetrick.blogspot.com -----
-- email feedback, corrections, request for copies or Index of all reviews
--- to: ------ jamesdetrick@comcast.net ------ “Jim Detrick” -----------
- https://plus.google.com/u/0/ -- www.facebook.com -- www.twitter.com
--------------------- Tuesday, May 26, 2020 -------------------------
-----------------------------------------------------------------------------------------

Monday, May 25, 2020

ASTRONOMICAL LADDER - How far does it reach?

- 2746 - ASTRONOMICAL LADDER - How far does it reach? The astronomical ladder is the method the astronomers learned to estimate the distance to the stars. The foundation of the ladder started 300 years before the birth of Christ. It was Eratosthenes the Greek who first figured out the Earth was a round sphere and had a circumference of 25,000 miles.
-

-
------------ 2746 - ASTRONOMICAL LADDER - How far does it reach?
-
- Eratosthenes was in the town of Syene, now called Aswan. He noted that on the 1st day of summer, June 21st, every year, the Sun shined to the bottom of a deep well. He discovered that at the same time of year in the town of Alexander a 10 foot pole cast a 16 inch shadow on the ground. Using this ratio 16 / 120 he determined the angle of the Sun’s rays to be 7 1/2 degrees. The distance between Aswan and Alexander was 50 days travel by camel. A camel’s speed is about 10 1/2 miles per day.
-
--------------- 10 1/2 * 50 = 525 miles
-
--------------- 525 miles would correspond to the 7 1/2 degrees as the circumference of the Earth would correspond to 360 degrees.
-
----------------- 360 /7.5 = Circumference / 525 miles.
-
----------------- Circumference = 25,200 miles.
-
- The camels must have been carrying lighter loads because today’s most scientific measurement is 24,900 miles. 99% accuracy 300 B.C. Amazing.
-
- Once we knew the Earth was round, and the diameter is 24,900 / pi = 7,926 miles, we could us parallax to measure the distance to the planet Mars. This is the next rung in the ladder. We line up Mars with a straight line to distance stars. We wait 12 hours and do it again.
-
- The parallax angle is the small angle the target moves compared with the distant stars. It moves 0.0092 degrees. The tangent of the right triangle for this small angle is 0.00016057. The tangent = Distance / diameter of Earth.
-
------------ Distance = 0.00016057 * 7,926 miles = 49,360,000 miles.
-
------------ Today’s science has the Earth at 227.9 million kilometers, Mars at 149.6 million kilometers from the Sun, making the Earth - Mars distance of 78.3 million kilometers, or 48,634,000 miles. Again, 99% accuracy using trigonometry.
-
- To get the next rung in the ladder astronomers used the discovery that the planet’s period of orbit squared is proportional to the radius of orbit cubed. They used this formula to estimate the distance to Jupiter. Jupiter’s period of orbit was measured to be 11.83 years. The Earth’s orbit is one year had a radius of 93 million miles.
-
------------ (11.83 years )^2 / 1 year^2 = (Jupiter’s orbit)^3 / (93 million miles)^3.
-
------------- 141 = (Jupiter’s orbit)^3 / 8.04*10^23
-
------------- Jupiter’s orbit = 483,300,000 miles.
-
- Today’s science puts Jupiter’s orbit at 483,416,000 miles.
-
- Now that astronomer’s had the Earth’s orbit at 93,000,000 miles they could wait 6 months between sightings and get a far bigger parallax angle. To calculate the distance to the stars they picked the brightest star Sirius, figuring that must be the closest. They got a parallax angle of 0.002075 degrees.
-
------------- Tangent 0.0020975 = 93,000,000 miles / Distance to Sirius.
-
------------ Distance to Sirius = 50,570,000,000,000 miles.
-
------------ A lightyear is 5,880,000,000,000 miles
-
------------- Distance to Sirius = 8.6 lightyears.
-
- By 1900 astronomers had calculated the distances for 100 stars. Parallax measurements had reached their limits, so, another method was needed for the next rung on the ladder.
-
- The brightness of stars varies inversely proportional to the square of the distance. By knowing the intrinsic brightness of Sirius and the distance to Sirius astronomers could calculate the distance to similar stars that were further away. Their brightness falls off as the square of the distance. If a similar star is 1% as bright it must be 10 times further away, 10 * 8.6 = 86 lightyears.
-
- To calculate distances out to 1,000 lightyears astronomers used a special kind of pulsating star called a Cepheid. These stars pulsate their brightness inversely proportional to the rate of the pulsations. The bigger the Cepheid star the more slowly it pulsates. And, the bigger the Cepheid star the brighter it shines.
-
- Polaris, the North Star, is the nearest Cepheid and its distance was determined to be 466 lightyears away. Cepheid stars have been used to take the astronomical ladder out to 60 million lightyears.
-
- To get the astronomical ladder out to 300 million lightyears astronomers used the light spectrum of hydrogen gas. Hydrogen gas emits a wavelength of 21 centimeters. Observing the 21 centimeter wavelength emitted from a rotating galaxy the discovered the Doppler effect.
-
- The wavelength was blue shifted on the side of the galaxy rotating towards us, and, the wavelength was redshifted on the side of the galaxy rotating away from us. The rotation speed of galaxies could be calculated. And, the rotation speed was proportional to the galaxy’s brightness. Knowing the brightness we could calculate the distance.
-
- Gravitational Lensing was used for the next rung on the astronomical ladder. Immense gravity can bend light. If there is a galaxy cluster of immense gravity between our line of sight and a distance Quasar we can use the lensing to calculate the distance to the Quasar.
-
- The Quasar is a super massive Blackhole in the center of a distant galaxy that emits pulsating jets. The light from these jets travels different paths through the gravitational lens. The same event on the Pulsar can be viewed months apart because of the different paths each light beam travels through the Gravitational Lens.
-
- The gravity caused space to curve and each light beam follows the shortest path through curved space. Measuring how much longer a second path has taken allows the distance the light traveled to be calculated.
-
- A star survives against gravity as long as its hydrogen fuel is burning. When the fuel runs out the star collapses under the force of gravity. The burn rate for a star is the cube of its size. A star 10 times bigger than the Sun will burn 1000 times faster. The Sun will burn for 10 billion years. The star 10 times larger will burn out living only 10 million years before it explodes as a supernova.
-
- If the core of the collapsing star is less than 1.4 Solar Mass it will collapse into a White Dwarf star, a Neutron Star, about 100 miles in diameter. If the mass at the core is greater than 1.4 Solar Mass it collapses into a Blackhole. Nothing can escape the gravity of a Blackhole.
-
- To escape the Earth’s gravity from the surface you need a rocket that can achieve a velocity of 24,000 miles per hour. The surface of the Earth is 3,963 miles above its center. If the Earth was 1/2 that size, 4 G’s, the escape velocity would be 1.4 times , or 33,600 miles per hour. If we collapsed the Earth down to a radius of 0.35 inches the escape velocity would be 186,000 miles per second. The Earth at that density would be a Blackhole.
-
- As an objects velocity approaches the speed of light, 186,000 miles per second, the mass increases, the length shortens, and the time slows down. At near light speeds mass is infinite, length is zero, and time stops.
-
- Obviously, only massless light can travel that fast. So, a super massive Blackhole presents us with physics we do not understand. But, we humans have only been working on these problems for a short time.
-
- If the age of the World were a calendar year, vertebrates did not appear until November 21st, primates did not show up until Christmas day and us Homo Sapiens got here just 3.5 minutes before New Year’s Eve. That is not much time to figure all this stuff out.
-
- But, we keep working at it and once the mind is stretched it never returns to its original shape. The astronomical ladder has stretched us out to 12.8 billion lightyears, where we see galaxies 12.8 billion lightyears distant.
-
- We need to discover another rung on the ladder.
-
- May 25, 2020 1108 2746
----------------------------------------------------------------------------------------
----- Comments appreciated and Pass it on to whomever is interested. ----
--- Some reviews are at: -------------- http://jdetrick.blogspot.com -----
-- email feedback, corrections, request for copies or Index of all reviews
--- to: ------ jamesdetrick@comcast.net ------ “Jim Detrick” -----------
- https://plus.google.com/u/0/ -- www.facebook.com -- www.twitter.com
--------------------- Monday, May 25, 2020 -------------------------
-----------------------------------------------------------------------------------------

May 25, recent index of Reviews

- Recent Reviews available, also by request.
-
- 2728 - UNIVERSE - is it the same everywhere? Is the Universe the same everywhere? Are the “natural constants” always the same regardless of where they are in the Universe? Recent studies and questions are proposing that not only does a “universal constant” seem annoyingly inconstant at the outer fringes of the cosmos, it may occur in only one direction.
-
- 2729 - COSMIC RAYS - to explain an expanding Universe? Could the Universe have expanded faster than the speed of light? The Universe appears to be “homogeneous” and “isotropic“ , the same in all directions. If light really was faster in the beginning then that could explain it. One way to test this theory is to study cosmic rays.
-
- 2730 - ASTRONOMY - has some amazing stories? These are stories of nature’s laws that we are trying to understand. What we learn is that the true universe is far stranger and more incredible than we can even imagine.
-
- 2731 - MOTION - in the heavens? Everything is in motion. Velocity s everywhere. Velocity is the change in space per the change in time. Space is expanding. Time moves forward. Neither are standing still. Everything we can witness in our Solar System appears to be in motion. But, how did we learn the motions in the sky starting with the Earth being stationary?
-
- 2732 - ASTRONOMY - more mysteries uncovered? Not only does a universal constant rate of expansion seem annoyingly inconstant at the outer fringes of the cosmos, it occurs in only one direction, which is weird. Astrophysicists continue to find hints that one of the cosmological constant is not so constant after all.
-
- 2733 - HIGGS BOSON - are there heavier bosons ? The Higgs particle is a piece of a field that permeates all of space-time. It interacts with many particles, like electrons and quarks, providing those atomic particles with mass. The Higgs boson is a subatomic particle first spotted in the Large Hadron Collider in Switzerland in 2012.
-
- 2734 - DECOHERENCE -the affects of the very small? - Quantum Mechanics is the science of the very small. It studies the behavior of fundamental particles the size of the atom or smaller. The physics of the very small produces some very strange results. Particles and waves interchange.
-
- 2735 - VENUS - explain its strange rotation ? Venus is unique in our Solar System because it is what’s known as a “super-rotator“. That means that Venus’ atmosphere rotates faster than the planet itself. Only Saturn’s moon Titan has the same characteristic.
-
- 2736 - HUBBLE - 30 years of astronomy? - The Hubble Space Telescope launched on the 24th of April, 30 years ago. One of the primary reasons for the Hubble telescope’s longevity is that it can be serviced and improved with new observational instruments through Space Shuttle visits.
-
- 2737 - QUASAR - the most distant light? When astronomers take a photo of the most distant light coming from a Quasar that is 13,000,000,000 lightyears away they are recording astronomical history. That same Quasar that was likely the center of an infant galaxy is now 46,000,000,000 lightyears away. That Quasar that is photographed at the center of a distant galaxy may not even exist today.
-
- 2738 - PHYSICS - Spacetime, Energy, and Calculus? clocks run slower as you go faster and faster, yes, that includes biological clocks. NASCAR drivers are younger than their twin brothers the accountants . Using Einstein’s equations you can actually calculate how much younger. But, I said this review would be Newtonian, actually it is whole course in Physics.
-
- 2739 - COSMIC RAYS - new discoveries? - A lot of what we know about the Standard Model of Nature’s fundamental particles came from studying Cosmic Rays. All ordinary matter that we know is made of Leptons and Quarks. Cosmic Rays are mostly protons that are made up of 3 Quarks.
-
- 2740 - BIG BANG - can‘t explain the universe we see? The Big Bang theory for the beginning of he Universe was pretty much understood. All the math worked out as expected at the time. Well, until astronomers tried to explain the behavior of other galaxies that were later discovered. Making sense of this will require still more new discoveries.
-
- 2741 - - PI - number Pi, who discovered it? We all learned about Pi in grade school. The area of a circle is Pi * (radius)^2. The circumference of a circle is 2* Pi*r. But where did this Pi come from?
-
- 2742 - PIEZOELECTRICITY - electricity from sound waves? Our energy problems could be solved. We could be generating electricity by talking, by simply moving, by walking, by running, by driving, and not changing anything we are already doing. By talking into your cell phone your sound waves could be charging up the phone. By driving on the freeway your tire noise could be running the street lighting.
-
- 2743 - ASTRONOMY - discoveries in astronomy? The last 50 years have brought many new discoveries to astronomy. This review starts in 1973 and brings us to 2020.
-
- 2744 - LIFE - will we find it on other planets? One of the driving forces in human curiosity is finding life on other planets. Will it be more advanced or will it be more primitive. The basic question is, “ Are we alone?” Whatever is out there, speak up!
-
- 2745 - PLANCK - satellite measures an expanding universe? Astronomers using X-ray data from these orbiting observatories studied hundreds of galaxy clusters, the largest structures in the universe held together by gravity, and how their apparent properties differ across the sky. This new discovery flies in the face of one of the pillars of cosmology, the study of the history and fate of the entire universe. Cosmology up to now maintained that the universe is ‘isotropic,’ meaning the same in all directions.
-
--------------------------------------------------------------------------------------
---- Comments appreciated and Pass it on to whomever is interested. ----
--- Some reviews are at: -------------- http://jdetrick.blogspot.com -----
-- email feedback, corrections, request for copies or Index of all reviews
--- to: ------ jamesdetrick@comcast.net ------ “Jim Detrick” -----------
- https://plus.google.com/u/0/ -- www.facebook.com -- www.twitter.com
------------------------- Monday, May 25, 2020 --------------------------------
-----------------------------------------------------------------------------------------

PLANCK - satellite measures an expanding universe?

- 2745 - PLANCK - satellite measures an expanding universe? Astronomers using X-ray data from these orbiting observatories studied hundreds of galaxy clusters, the largest structures in the universe held together by gravity, and how their apparent properties differ across the sky. This new discovery flies in the face of one of the pillars of cosmology, the study of the history and fate of the entire universe. Cosmology up to now maintained that the universe is ‘isotropic,’ meaning the same in all directions.

---------------- 2745 - PLANCK - satellite measures an expanding universe?

- Most of us that are the least bit interested in science have learned that we live in an expanding Universe . It started as a Big Bang some 13,700,000,000 years ago. Our Planet as been on this ride some 4,500,000,000 years.

- The Milky Way Galaxy that we are riding in is just one among billions and billions of galaxies out there in the cosmos. Once beyond the reach of gravity they are racing away from each other at an ever increasing acceleration.

- The Universe is expanding, but, it may not be expanding at the same rate in all directions? One of the fundamental ideas of cosmology is that everything looks the same in all directions if you look over large enough distances. A new study using data from NASA’s Chandra X-ray Observatory and ESA’s XMM-Newton is challenging that basic notion.

- Astronomers using X-ray data from these orbiting observatories studied hundreds of galaxy clusters, the largest structures in the universe held together by gravity, and how their apparent properties differ across the sky.

- This new discovery flies in the face of one of the pillars of cosmology, the study of the history and fate of the entire universe. Cosmology up to now maintained that the universe is ‘isotropic,’ meaning the same in all directions.

- Astronomers generally agree that after the Big Bang, the cosmos has continuously expanded. A commonly analogy is that this expansion is like a baking loaf of raisin bread. As the bread bakes, the raisins (which represent cosmic objects like galaxies and galaxy clusters) all move away from one another as the entire loaf (representing space) expands. With an even mix the expansion should be uniform in all directions, as it should be with an isotropic universe.

- Scientists have previously conducted many tests of whether the universe is the same in all directions. These included using optical observations of exploded stars and infrared studies of galaxies. Some of these previous efforts have produced possible evidence that the universe is not isotropic, and some have not. The data to date was inclusive.

- This latest data comes from test using a powerful, novel and independent technique. It capitalizes on the relationship between the temperature of the hot gas pervading a galaxy cluster and the amount of X-rays it produces, known as the cluster's X-ray luminosity.

- The higher the temperature of the gas in a cluster, the higher the X-ray luminosity is. Once the temperature of the cluster gas is measured, the X-ray luminosity can be estimated. This method is independent of cosmological quantities, including the expansion speed of the universe.

- Once they estimated the X-ray luminosities of their clusters using this technique, scientists then calculated luminosities using a different method that does depend on cosmological quantities, including the universe’s expansion speed. The results gave the researchers apparent expansion speeds across the whole sky. This result is revealing that the universe appears to be moving away from us faster in some directions than others.

- This new study came up with two possible explanations for their results that involve cosmology. One of these explanations is that large groups of galaxy clusters might be moving together, but not because of cosmic expansion.

- For example, it is possible some nearby clusters are being pulled in the same direction by the gravity of groups of other galaxy clusters. If the motion is rapid enough it could lead to errors in estimating the luminosities of the clusters.

- These sorts of correlated motions would give the appearance of different expansion rates in different directions. Astronomers have seen similar effects with relatively nearby galaxies, at distances typically less than 850 million light years, where mutual gravitational attraction is known to control the motion of objects.

- However, scientists expected the expansion of the universe to dominate the motion of clusters across larger distances, up to the 5 billion light years probed in this new study.

- A second possible explanation is that the universe is not actually the same in all directions. One intriguing reason could be that dark energy, the mysterious force that seems to be driving acceleration of the expansion of the universe, is itself not uniform. In other words, the X-rays may reveal that dark energy is stronger in some parts of the universe than others, causing different expansion rates.

- This conclusion would be like if the yeast in the bread isn’t evenly mixed, causing it to expand faster in some places than in others. It would be remarkable if dark energy were found to have different strengths in different parts of the universe.

- Either of these two cosmological explanations would have significant consequences. Many studies in cosmology, including X-ray studies of galaxy clusters, assume that the universe is isotropic and that correlated motions are negligible compared to the cosmic expansion at the distances probed here.

- This team used a sample of 313 galaxy clusters for their analysis, containing 237 clusters observed by Chandra with a total of 191 days of exposure, and 76 observed by XMM-Newton, with a total of 35 days of exposure.

- They also combined their sample of galaxy clusters with two other large X-ray samples, using data from XMM-Newton and the Japan-US Advanced Satellite for Cosmology and Astrophysics (ASCA), giving a total of 842 different galaxy clusters. They found a similar result using the same technique.

- So mysteries remain: Is the expansion rate really the same everywhere? What are we expanding into? Is there something beyond “space” out there? We have to leave something for new students to work on. The more we learn it seems to uncover still more to be learned.

------------------------------------ Other Reviews available:

- 2167 - PLANCK - measures the Cosmic Microwave Background. We have a Universe with 5% normal matter, 27% dark matter, and 68% dark energy. At last, we can state, with extraordinary confidence, what the Universe is made of. The curvature of the Universe is no greater than 1-part-in-1000, indicating that the Universe is indistinguishable from perfectly flat. Where have I heard that before? Christopher Columbus did not believe it either.

- 1653 - Discoveries of Planck Telescope on Universe Evolution. The data collected tells astronomers how old the Universe is and its composition today. 95% of this composition is “ dark” , unknown to science. With these parameters they can still simulate the expansion of the Universe to what we see today.

- 1586 - Measuring the Cosmic Microwave Background . The density waves in the radiation tell us much about the structure and composition of the Universe. If your eyes were sensitive to microwave frequencies and you were above the atmosphere the sky would have a similar background color over the entire sphere. If we translate this microwave frequency to a visible light frequency we could make it a cold light blue color that would be homogeneous in all directions. The color of this background would be 2.735 degrees Kelvin.

- 1305 - “Cosmic Harmonics” The temperature of the background is 2.735 Kelvin which is nearly Absolute Zero and nearly homogeneous, but, not quite perfectly smooth at the very high resolution. At the highest resolution the temperature variations existed at 0.0005 Kelvin. Those “ hot spots” that started out due to quantum fluctuations have evolved into the stars and galaxies we see today.

- 1108 - How Far Does the Astronomical Ladder Reach? The astronomical ladder is the method the astronomers learned to estimate the distance to the stars. The foundation of the ladder started 300 years before the birth of Christ.

- 823 - Sound Waves and the Cosmic Microwave Background. The Big Bang blast created sound waves that can be heard even today. The sound waves of alternately compressed and rarefied regions of plasma were transmitted through the plasma must like sound waves travel through air. Plasma is a soup of ionized particles and photons that first emerged after the Big Bang. Ionized particles are atomic nuclei that have lost their electrons and therefore become electrically charged. Charged particles scattered the photons and made the plasma opaque.

- 757 - Cosmic Background Radiation. Astronomers believe it is compelling evidence for the Big Bang. The radiation has been studied for 3 decades. The radiation left the Big Bang as Gamma Rays and has stretched with the expansion of the Universe to where the wavelengths are in the millimeter to centimeter wavelength, which is the microwave frequency range.

- May 25, 2020 2745

----------------------------------------------------------------------------------------

----- Comments appreciated and Pass it on to whomever is interested. ----

--- Some reviews are at: -------------- http://jdetrick.blogspot.com -----

-- email feedback, corrections, request for copies or Index of all reviews

--- to: ------ jamesdetrick@comcast.net ------ “Jim Detrick” -----------

- https://plus.google.com/u/0/ -- www.facebook.com -- www.twitter.com

--------------------- Monday, May 25, 2020 -------------------------

-----------------------------------------------------------------------------------------

JimsAstronomy