Asteroids, Meteors, Meteorites, and Micro-Meteorites

By: Arianna Good

Asteroids, meteors, and meteorites
If you look up into the night sky, you are not just seeing stars. You are also seeing planes as en route to their next destination and rotating satellites as they orbit our earth. On a rare occasion, however, one may just be lucky enough to see a meteorite which is most commonly referred to as a shooting star. However, do not get a meteorite confused with an asteroid. There are many misunderstandings about asteroids, meteors, and meteorites. While all of these rocks originate from space, they have different names depending their location, such as whether they are hurtling through space or hurtling through the atmosphere and impacting Earth’s surface.

In simple terms, an asteroid is a large rocky body in space, in orbit around the Sun while meteoroids are much smaller rocks or particles in orbit around the Sun. If a meteoroid enters the Earth’s atmosphere and vaporizes, it becomes a meteor, which is often called a shooting star. On the other hand, if a small asteroid or large meteoroid survives its fiery passage through the Earth’s atmosphere and lands on Earth’s surface, it is then called a meteorite. Another related term is bolide, which is a very bright meteor that often explodes in the atmosphere. This can also be called a fireball.

Image: A diagram which helps illustrate the difference between meteoroids, meteors, and meteorites

Micro-Meteorites
According to researchers from Swedish Lund University and US Universities of Chicago and Wisconsin-Madison, it was found that micro-meteorites have revealed a surprising instability of our universe. The team studied 43 meteorites which were found on the sea floor of the Lynna River in Russa and supposed to have fallen to Earth 470 million years ago. By comparing this finding of meteorites to research from 2016 of a different meteorite, it was found that the flow of meteorites 500 million years ago was completely different to today's and our current understanding of our solar-system's stable history mus now be revised.

Image: Micro-meteorites found by James K. Bowden in 2012 at the Franconia Meteorite Strewn

Gravitational Waves

Gravitational Waves

The Discovery:

• The discovery of gravitational waves has been declared the breakthrough of the year
• Physicists announced they heard the subtle rumbling of a ripple in spacetime which is the result of two black holes colliding
• These observations confirmed the existence of gravitational waves
• These waves were predicted by Albert Einstein more than 100 years ago
• The waves were picked up by two huge science experiments called the Laser Interferometer Gravitational-Wave Observatory
• This discovery launched a whole new branch of science
• Right now, our telescopes can only see objects that emit electromagnetic radiation  (visible light, X-rays, gamma rays)
• Some objects like colliding black holes, don't emit any electromagnetic radiation but they do emit gravity. So with gravitational wave astronomy, invisible objects in the universe may soon become visible
  
  

Why the waves matter:

• Just as sound waves disturb the air to make noise, gravitational waves disturb the fabric of spacetime to push and pull matter as if it existed in a funhouse mirror
• If a gravitational wave passed through you, you’d see one of your arms grow longer than the other. If you were wearing a watch on each wrist, you'd see them tick out of sync
• Gravitational waves are generated by any movement of mass
• The only way to detect gravitational waves that faint is from a really loud source like the collision of two black holes
• Two black holes colliding unleash a loud thunderclap of gravity. But by the time they reach Earth 1.4 billion years later, they are not as loud
• This compares to how pond ripples become less frenzied farther away from a dropped stones
• Gravitational waves are comparable to the frequencies of the sound waves we hear
• One of the waves heard was around 0.7 attometers tall, much smaller than an atom
  
  

How the Experiment is conducted:

• There are two massive experiments, both are giant L-shaped tubes. Each arm of the tube is 2.5 miles long
• During the experiments, a laser beam is equally split between the two arms. At the end of each arm is a mirror, which reflects the laser back to the starting point
• Scientists are looking for evidence that gravitational waves are distorting spacetime enough that one of the arms becomes temporarily longer than the other
  
  

Facts About Gravitational Wave Astronomy:

• Scientist can’t just point at a region in the sky to search for gravitational waves, they can just hear the gravitational waves that are passing through Earth at any particular moment
• The area where the waves are coming from is hard to determine
• Gravitational wave astronomy could accomplish
• Seeing further back in time
• If you look with visible light as far as we can look in the universe, the universe is no longer transparent, instead it is opaque
• Improving on Einstein’s theory of general relativity
• Physicists have speculated that the theory isn’t complete
• Gravitational waves could help physicists put general relativity to harder and harder tests to see where it fails
• Discovering new neutron stars
• Neutron stars are the extremely dense cores of collapsed stars that can emit large amounts of gravity
• Black holes orbiting to one another
• Gravitational wave astronomy will help us understand how many of these pairs exist in the universe
• Finding the source of dark matter
• Dark matter is theorized to make up 27 percent of all the matter in the universe.
• Matter creates gravity
• Perhaps gravitational waves can help us trace the origins of dark matter

Citation:

• Resnick, Brian. "Why Gravitational Waves Truly Are the “scientific Breakthrough of the Year”." Vox. Vox, 22 Dec. 2016. Web. 11 Jan. 2017.
  
  
  Jared Blatt
  Mr. Gray
  Period G
  11 January 2017

'Caterpillar' Robot Wriggles to Get Around

'Caterpillar' Robot Wriggles to Get Around 

Robotic innovations are helping scientists understand and combat environmental threats such as pollution and global warming. Robots are the future, as robots are used for gathering data, to conserving resources, and eliminating hazardous materials, robots will one day save the planet. The new robot inspired by a caterpillar, might one day climb trees to monitor the environment. 

Traditional Robots: 
Robots have in the past been made from rigid parts, which make robots susceptible to harm from bumps, scrapes, twists, and falls. Robots are restricted due to their rid and heavy parts, these restrictions keep robots from being able to wiggle their way past obstacles. 

                                             

New Material that will Change Robotics 

As Scientist thought of the future of robots they came up with robots who are made up of soft body parts, that will improve the abilities of a robot. These "soft" robots will be more resistant to damage and can squirm past many of the obstacles the once impaired the hard robots. Scientist are building these soft robots out of bendable plastic and rubber parts that are inspired after boneless creature; for example octopuses, starfish, worms, and caterpillars. 

"I believe that this kind of robot is very suitable for our living environment, since the softness of the body can guarantee our safety when we are interacting with the robots," said lead study author Takuya Umedachi, now a project lecturer in the Graduate School of Information Science and Technology at the University of Tokyo.

                               

Soft Material 

The only problem with soft material is it deforms very easily thus making it difficult to control when conventional robotics techniques are used. Udemachi predicts to his colleagues that the soft a material must be monitored due to the unexpected ways in which such robots can move.
Umedachi and his colleagues need to figure out a better way to control the soft robots. They researched the caterpillars of the tobacco hornworm Manduca sexta, hoping to learn how thee animals coordinate their motions without a hard skeleton. Caterpillars are extraordinary animals that are able to move in complex ways without having complex brains.

                         

Caterpillars 

Caterpillars are the perfect animal to base this new robot of off, for the reason that caterpillars do not rely on a control center like the brain to steer their bodies. Caterpillars have a very small number of neurons, Scientists have suggested that caterpillars control their own bodies in a more decentralized manner. This new robot is model after the caterpillar because there is a theory that sensory neurons are embedded in soft tissues that relay data to groups of muscles that can then help caterpillars move in a concerted manner. The new robot was inspired off the animals body, sensors were placed on the robot's soft body that can deform as it interacts with its environment. Scientists found out that the could use this sensory data to guide the robot's inching and crawling motion with very little guidance. Thus making a caterpillar the perfect inspiration for the future robots. 

Gabriella Pedro 

Mr. Gray 

Honors Physics 

January 11, 2017 

Launching Drugs from Red Blood Cells using Light

Researchers at the University of North Carolina at Chapel Hill have made breakthrough discovery. This technique could be very rewarding in the medical field, as it allows the transport and release of drugs by red blood cells using light at precise locations throughout the body.

The research was led by Fred Eshelman Distinguished Professor David Lawrence in the Ethelan School of Pharmacy. This technique will allow physicians to administer drugs at exact locations in the body by using red blood cells. This is an amazing breakthrough, as it will allow doctors to administer a lower amount of drugs for more effcective results. Also, it will allow them to target individual parts of the body, making the drugs more effective. 

Lawrence and his team attached a drug molecule to vitamin B12 and loaded the compound into red blood cells. They were then able to use long-wavelength light to penetrate deep enough into the body to break molecular bonds; in this case, the drug linked to vitamin B12. This allowed the red blood cells to release the drug. This method is also very promising because it allows the red blood cells to circulate the drug for up to months, so treatment will not be needed as often.

Peyton Phillips

Link: https://www.sciencedaily.com/releases/2017/01/170104143603.htm

The Technology of Self-Driving Cars

The Technology of Self-Driving Cars 

How do Self-Driving Cars Work 

Tesla, Nissan, and google all claimed that within the next five years they will be able to produce a completely self-driving car. Self-driving cars require a GPS Unit, an internal navigation system and a ton of different sensors. This abundance of sensors usually include a camera sensor, radar sensor, and a later rangefinder sensor. These machines are used in unison to location the position of the car in three dimensions.

The Physics Behind the Speed

The car used all of its sensors and to plan a path two a specific destinations while following the rules of the road, and avoiding obstacles and cars. Different Cars have different sensors, and therefore gather different information, but the some basic information needs to be collected by all self-stopping cars such as speed, direction, and angular position. The car, uses physics allgorithims throughout the entire trip, has to calculate whether it is possible for a car, traveling at any certain speed, to be able to change lanes, take certain turns, and go down certain paths. A laser rangefinder scans the environment using  laser beams and calculates the distance to nearby objects by measuring the time it takes for each laser beam to travel to the object and back.  Laser rangefinders use that depth information for building a three-dimensional map. A vehicle’s internal map includes the current and predicted location of all static and moving  obstacles in its vicinity. The vehicle uses a probabilistic model to track the predicted future path of moving objects based on its shape and prior trajectory. This process allows the vehicle to make decisions. For example, a vehicle traveling at 50 mph would not be able to safely complete a right turn 5 meters ahead, therefore that path would be eliminated from the feasible set. After evaluating feasible paths, the car  can make safe decisions. Remaining paths are evaluated based on safety, speed, and any time requirements. Once the best path has been identified, a set of throttle, brake and steering commands, are passed on to the vehicle’s on-board processors and actuators. Altogether, this process takes on average 50ms, although it can be longer or shorter depending on the amount of collected data, available processing power, and complexity of the path planning algorithm.

Limitions

Car manufactures have made huge strives to create self-driving cars, but there are still large problems that stand in the way of the average American obtaining a self-driving car in the near future. Some of these issues include the unreliability of GPS maps, cars not know all of the different aspects of every road, weather condition, road detours, and other types of things that cannot yet be processed by a computer while driving. These limitations will be able to be overcome, but the self- driving will be slowly integrated into the average population. Many people will not be able to afford a self driving car for many years, and many of the self driving cars will not be completely, self-sufficent for many years to come. 

The Physics of Planes

   The Physics of Planes 

          Airplanes are constructed in a way that the airflow pattern around them generates lift, which enables them to fly. The airflow is produced by the forward motion of the plane relative to the air. This forward motion is produced by engine thrust, delivered by way of propeller engines or air-breathing engines, otherwise known as turbines. Airplane engines produce thrust by accelerating the airflow in the rearward direction. This backwards acceleration of the airflow exerts a "push" force on the airplane in the opposite direction, by Newton's third law that there is an equal and opposite reaction, causing the airplane to move forward. 

Airfoils

          In aerodynamics, airplane wings are called airfoils. They have a cambered shape which enables them to produce lift, even for angles of attack (α) equal to zero. The figure below is a cross-sectional view of an airfoil. 

           The orientation of the airfoil relative to the airplane body is shown below. The angle of incidence is defined as the angle between the chord line and the longitudinal axis of the plane. For general aviation designs, an angle of incidence commonly used is about 6 degrees. 

Forces acted on the Plane 

The figure below shows the resultant forces acting on an airplane in level flight, moving at constant velocity. 

 

Since the airplane is moving at constant velocity it is experiencing zero acceleration, and the forces must balance. This means that the lift force (L) generated by the airplane wings must equal the airplane weight (W), and the thrust force (T) generated by the airplane engines must equal the drag force (D) caused by air resistance. This balance allows the plane to stay in te sky and produce a safe flight.

Taking off and Landing 

          An airplane undergoing takeoff, or landing, experiences similar forces acting on it. The figure below shows the typical forces acting on an airplane during takeoff. Note that the lift force (L) is defined as perpendicular to the velocity (V) of the plane relative to the air. The drag force (D) is defined as parallel to the velocity (V). As one would expect, the thrust force (T) is in the same direction as (V). The weight (W) of the plane points straight down in the direction of gravity. Now, W = mg, where m is the mass of the plane and g is the acceleration due to gravity, where g = 9.8 m/s². 

 

If the plane is moving at constant velocity with respect to ground then all the forces acting on the plane must be balanced. This means that in the vertical direction the sum of the forces is equal to zero, and in the horizontal direction the sum of the forces is equal to zero. Mathematically, in the vertical direction:

Equation: Lcosθ + Tsinθ - Dsinθ - W = 0

In the horizontal direction: 

Equation: Tcosθ - Dcosθ - Lsinθ = 0. 

If the plane is experiencing acceleration one can use these force equations, by including acceleration terms in the force equations, using Newton's second law.

Maneuvering and Navigation

             Airplanes control their navigation path and attitude (orientation relative to the direction of air flow) by adjusting physical elements on the outside of the airplane, elements which modify the airflow pattern around the plane, causing the plane to adjust its attitude and flight path. These physical elements are called control surfaces and consist of ailerons, elevators, rudders, spoilers, flaps, and slats. Adjusting a plane's flight path always involves either pitching, rolling, or yawing, or a combination of these. The figure below illustrates what these are. 

 

 

We can analyze this as follows. 

By Newton's second law, the force balance for the centripetal acceleration, in the lateral direction, is given by 

 

where θ is the bank angle, m is the mass of the plane, V is the velocity of the plane (normal to the page) with respect to ground, and R is the radius of the turn. 

The force balance in the vertical direction is given by 

 

Combine the above two equations to give the radius of the turn. We have 

 

sources:

http://www.portageinc.com/community/pp/flight.aspx

http://www.lcse.umn.edu/~bruff/bernoulli.html

http://www.real-world-physics-problems.com/how-airplanes-fly.html

https://www.grc.nasa.gov/www/k-12/airplane/forces.html

Rainbows

There is a physics to rainbows. A rainbow happens When light meets an interface between air and water some of it is reflected and some of it passes through. The angle of refraction depends both on the light’s wavelength and on the angle at which it hits the surface. Wavelength corresponds to color, so the colors separate into the familiar bands, which creates the color. 

Local changes in the rain shower can affect the mirror rainbow completely differently from the direct-view rainbow. The Size of the rain drop contribute at the base, whereas near the top, light from the large. Larger raindrops are squished flatter on the underside by air resistance as they fall and usually make up a small fraction of a rain shower. Our understanding of rainbows is very robust now, but not complete. There are undoubtedly details that can still be improved.

Engineered "Sand" May Help Cool Electronic Devices

Physics Blog 4

Scientists have developed an engineered silicon dioxide nanoparticle coated with a high dielectric constant polymer used to improve cooling for increasingly power consuming electronic devices. In todays ever expanding world, technology is become more and more advanced, and looks to become more efficient. Engineer Baratunde Cola created the silicon dioxide, or sand for your computer" as a revolutionary way to cool the core of computers.

The silicon dioxide, covered with the high dielectric constant polymer, has unique surface properties that conduct heat at potentially higher efficiency than existing cooling materials. The nanoscale electromagnetic effects on the surface of the silicon dioxide act together allowing a strong heat controlling and conducting material.

Technology including electronics, LEDs, and household applications could, in time, have the silicon dioxide placed inside in order for strong heat dissipation, or becoming cooler. This would work by taking a packed nanoparticle bed (of silicon dioxide seen in there image below) that would normally act as an insulator, enacting light to couple strongly into the material bu engineering a high dielectric constant medium, and hence turning the nanoparticle bed into a conductor of heat in this case. When material are reduced to extremely small nanometers, the surface properties of the material dominate over but properties, allowing the photons of heat the flow from one particle to another in the closely packed bed.

According to Cola, the electronic device would be packed with ethylene glycol-coated nanoparticles in the air space, proving that they would be as efficient as typical heat dissipation materials, that in addition won't conduct electricity cause less heat to be emitted in the process.

Silicon dioxide is used because the crystalline lattice that it possesses generates resonant optical phonons at room temperature while providing a good compromise of general properties and cost from the others. Silicon dioxides extremely hard, having very high boiling and meting points, and does not conduct electricity. It is also insoluble in water, where these properties all result in strong covalent bonds, allowing heat to pass through and absorb well.

Baylor Wallace

January 11, 2017