Infrared light shows the deepest view of distant galaxies ever photographed. JWST Photo: NASA Public Domain
Overview
The question of extraterrestrial life on other worlds has baffled even the foremost scientists for millennia. With the Hubble telescope and now, the James Webb telescope floating in the cosmos a million miles from Earth, we are finding more and more life-sustaining planets on a frequent virtual basis.
This is different from space observatories, which can determine the existence of exoplanets by spectrum analysis, calculating their gravitational pull from their sun, or using the transit method—an observational process whereby a star changes in brightness when a planet is seen orbiting around it. The JWST’s advanced technology surpassed those methods by taking pictures of these exoplanets. This is the first time this has ever been done!
Exoplanets with Life? Maybe!
In 2013, a team of astronomers led by Dr. Duncan Wright from the University of New South Wales discovered the Wolf 1061 System using the HARPS spectrograph, part of the European Southern Observatory’s telescope in La Salla, Chile.
This solar system contains an inactive red dwarf star, orbited by possibly seven planets, including three super-Earths. These planets may be capable of supporting life as we know it, as they have a low enough mass to be potentially rocky with a solid surface.
The most interesting of the three planets is Wolf 1061c. At four times the size of the Earth, it is the closest habitable planet outside our solar system. It also sits in the Goldilocks Zone, close enough to its sun to contain liquid water and support life with its mild temperatures.
Artist’s impression of the planetary system around Wolf 1061. Photo: Wikipedia Public Domain
Based on these readings, scientists speculate that iron deposits, as well as silicates (elements that contain the minerals silicon and oxygen), may exist on the planet, which are very common.
Still, with the hope of Wolf 1061c sitting right next door, scientists are now hopeful that they can test the planet’s atmosphere in more detail once it passes across the face of its star, making the not-so-lone Wolf planet easier to study and determine if it has the potential to sustain life.
Even though rocky planets similar to our own and multi-planet systems are known to be abundant in our galaxy, most of the ones discovered are hundreds, if not thousands, of light years away. They are too far for us to reach using current technology.
Life is Out There
Photo: iStock
Here, we list a sampling of just a few exoplanets that could sustain life.
WASP-39 b
In 2022, the James Webb Telescope discovered a planet called WASP-39 b in the Virgo constellation. Known as ‘Bocaprins’, the planet orbits a star about 700 light-years from Earth. Scientists were surprised to see that this planet’s atomic structure resembles water and carbon – two of the essential ingredients of universal life.
Kepler-186f
But that’s not all. Planets such as Kepler-186fare among those astronomers say have a perfect chance of potential life relative to the hundreds of other planets discovered outside our solar system. Kepler-186f is the first exoplanet found to be in the habitable zone. Slightly larger than Earth, it is 490 light-years away, which is not too far.
Kepler-22b
Another close neighbor in the habitable zone is Kepler-22b. This body is about 150 light-years further away than Kepler-186 but has the promise of life just the same. It is about 15% closer to its sun than our Earth is to our sun, but its sun is smaller than ours, so there is a compensation effect where these two factors cancel each other out.
Subsequently, it still allows the planet to remain in the habitable zone. Kepler-22b has a surface temperature of 72℉. This sounds like a good vacation spot when we get to that point of space travel. For Star Trek fans, you can envision the beautiful planets the crew visited when on shore leave. Well, not so fast.
Kepler-22b might be more on its axis than Earth, meaning half of the planet may have all sunlight 24×7, and the other half may be in complete darkness for every (of that) planet’s six months. Further studies have revealed that the planet may be 90% ocean or more, compensating for seasonal issues.
Additionally, Kepler-22b has been calculated to have a much stronger gravitational pull than our planet, so walking on this planet may be as hard as walking briskly through the water at the same speed as walking on land.
But if there are creatures on this planet, intelligent or not, natural evolution may cause these beings to look much different from us. Due to the planet’s strong gravitational pull, the aliens may have budging feet full of muscles that would make the strongest man in the world look like a stick figure. They may have more than just two or four legs. Additionally, their internal organs would have to be naturally engineered to handle the physical stresses of the planet’s strong gravity, such as an overly large heart.
The Day the Earth May Stand Still
If Kepler-22b is life-sustaining, it would take astronauts 635 years to get there. Since that is out of the question for us, if intelligent life exists there or on other planets, their technology might provide a quicker way to visit us. But is that what we would want?
From tragedy to triumph, a tower soars 104 stories, 1,776 feet high, representing the year the Declaration of Independence was signed.
One World Trade Center (AKA The Freedom Tower) opened to businesses on November 3, 2014, and the three-story observatory, which opened on May 29, 2015, invites visitors to a spectacular view of the New York skyline.
Skidmore, Owings & Merrill, famous for designing some of the most notable modern tall buildings throughout the world, were the primary architects, under the supervision of designer David Childs. The firm, also known as SOM, was the architect of the Burj Khalifa and Chicago’s Willis Tower (formerly the Sears Tower).
The Preliminaries
Soon after the tragic destruction of the original World Trade Center (Twin Towers), the Lower Manhattan Development Corporation initiated proposals for the reconstruction of a new tower, as well as a plan to memorialize the victims of the September 11 attacks.
When the public rejected the first round of designs, a second, more open competition took place in December 2002, in which a blueprint by Daniel Libeskind was selected as the winner. This design went through many revisions, mainly because of disagreements with developer Larry Silverstein, who held the lease to the World Trade Center at that time.
Construction began on April 27, 2006, but not after continuous delays and ongoing bureaucracy, including disputes between the Port Authority of New York and New Jersey and the developer Tishman Realty & Construction. The Tishman construction firm was famous for its participation in building some of the tallest buildings in New York City, including the original World Trade Center complex and the John Hancock Center in Chicago. John Tishman died on February 6, 2016.
No doubt that security was a prominent concern in the design and construction of this tower, and terrorism was indeed a major consideration.
No one was more concerned than the NYPD, and after many debates and delays, the final proposal for the Freedom Tower 11-Year was approved and shown to the public on June 28, 2005, with a 187-foot base of concrete added.
Additionally, the building had installed stainless steel panels and blast-resistant glass. The Freedom Tower is designed to withstand earthquakes and has an elaborate security facility integrated within it.
In addition to 24×7 monitoring, there is a high-tech security system that includes video analysis in which computers would alert security personnel to abnormal situations automatically.
There are additional security apparatuses that have been installed, but their actual function has not been made public. What is known is that there are radiation detectors abound in lower Manhattan and the NYPD Hercules Team is ready at a moment’s notice.
Building the Skyscraper
On November 18, 2006, 400 cubic yards of concrete were poured onto the building’s foundation.
On December 17, 2006, a ceremony was held in Battery Park City, with the public invited to sign a 30-foot (9.1 m) steel beam. The beam was welded onto the building’s base on December 19, 2006. Construction was slow but continuous.
One World Trade Center (Freedom Tower) under construcion. (L-R) March 2010 and November 2011. Photo SMS
In 2012, workers installed the steel framework at the top of the tower to support the 408-foot spire. The spire was fabricated as 16 separate sections at a factory near Montreal, Quebec, and was transported by barge to New York City in mid-November of that year.
On May 10, 2013, the final component of the skyscraper’s spire was installed, making the building, including its spire, reach a total height of 1,776 feet, representing the date of the Declaration of Independence.
Negotiating the Wind Forces
Optimizing One World Trade Center for high winds was unique as the tower’s design included a geometrical shape that helps reduce exposure to wind loads.
Additionally, the core has reinforced concrete which provides the main support against resistance to the wind forces and other forces of nature.
The One World Trade Center observatory opened on May 29, 2015, and is currently the highest of the four observatories in the city at 1,268 feet.
There are three floors, including exhibits and a restaurant.
The most convenient way to purchase tickets would be to purchase them online.
Surrounding Area
World Trade Center North Tower Reflecting Pool. Photo: Wikimedia Public Domain
Visitors who come to the Freedom Tower should also visit the 911 Memorial, which is a tribute to the 3,000 people who were lost, including the first responders.
The memorial contains the footprints of the former Twin Towers. It has continuous running water over two one-acre pools, one for each of the towers, called “Reflecting Absence“, signifying the physical void left by those who were lost.
Skyscrapers are defined as being at least 330 feet (100 meters) high with supertalls classified as 984 feet (300 meters) and mega tall at 1,968 feet (600 meters) or higher.
From the Burj Khalifa in Dubai to the Shanghai Tower in China and the Empire State Building in New York, there is no doubt that these structures are a marvel of modern engineering and they stand as a testament to human ingenuity and perseverance. For architects and engineers, the challenge to design them is complex.
From the foundation to the roof, they are carefully planned and executed by scivi engineers, which might take years to complete before even one brick is laid down. Considerations towards building codes, structural stability, aesthetics, and of course economics are primary factors to be studied.
Exploring the making of skyscrapers is an exciting journey for anyone interested in how tall buildings are constructed. This article is a credit to the dedication to the architects and engineers who build them.
Enter the Forces of Nature
Burj Khalifa, Dubai, UAE – Tallest Building in the World. Photo by Wael Hneini on Unsplash
Wind loads (wind forces) that hit the buildings can cause them to sway. The higher the building is, the more wind it will be subject to.
Skyscrapers will sway and can easily move several feet in either direction.
To reinforce the structure to withstand these winds, there are several options that engineers will use.
Empire State Building – A Prime Example of Mitigating Wind Forces
Before we delve into the engineering specifics, let’s get familiar with the general idea of how buildings suppress wind forces and what better example to use than the famous Empire State Building?
Most tall buildings use multiple methods to mitigate strong winds, so let’s take a look at what engineers have done with this 1,472-foot-high iconic structure.
Streamlined shape: The building has a tapered shape that reduces wind resistance and helps to distribute wind forces evenly across the building. More commonly known as setbacks.
Wind bracing: The building has a series of steel braces that run diagonally between the exterior columns, which helps to provide additional support and stability against wind forces.
Corner columns: The building’s corner columns are larger and stronger than the interior columns, which helps to distribute wind forces more evenly throughout the building.
Tuned mass damper: The building has a large pendulum-like device called a tuned mass damper located on the 58th floor. The damper helps to counteract wind-induced building oscillations by moving in the opposite direction of the building’s sway, effectively damping out the oscillations.
Now let’s take a look at the process from start to finish.
Designing the Structure
3D rendering with construction specifications using CAD software. Photo: iStock
Economics always comes into play, so whatever the planned design is, it must be within the developer’s budget. Architects use computer-aided design (CAD) software to create 3D models of a building.
Usually created on networked desktop computers, CAD is used primarily for analyzing and optimizing a building’s design.
Of course with skyscrapers, there may be hundreds of CAD diagrams that would be needed. The software includes the building codes that they must follow.
It should go without saying that structural stability is of the utmost importance and the foundation is the first step in helping to buttress the building from the forces of nature to which these buildings may be subject.
Beginning with the foundation, engineers must determine if the soil below the building is strong enough to support the structure. A good example is in New York City where there is solid bedrock that makes it perfect for the construction of skyscrapers.
Steel and concrete are the most commonly used materials for foundations. Concrete is strong under compression, but not as strong under tension, and in its pure form, it is unsuitable to withstand the stresses of the wind forces and vibrations,
To compensate for this lack of tensile strength, workers pour a liquid concrete mixture into a wire mesh steel frame, called rebar or reinforcing bar, which strengthens the tension component of the concrete. Together, the product is known as reinforced concrete and forms a strong solid foundation to support any tall building.
Strong Internal Cores
One of the most popular methods for mitigating wind forces is the ability to build strong cores in the center of the building. Usually constructed around the elevators are solid steel and/or concrete trusses, braced by steel beams.
Most of the tall buildings of the 20th century use this method and it is still going strong into the 21st century, but usually, there are more obstacles to the wind added, especially if the building is of the super or mega tall variety.
Corner Softening
Taipei 101 in Taiwan China uses corner softening to dampen the winds
This is a style that softens the edges of tall buildings to reduce the vortices (strong winds) that these structures are subject to.
The 1,667-foot Taipei 101 in Taiwan uses this method which is very effective in controlling high winds.
But that’s not all Taipei 101 uses against wind vortices as we will see below.
In 1916, due to the shadow effect that tall buildings would leave on the sidewalks of New York, specifically, the 555-foot tall Equitable Building that was completed a year before, a new zoning law was enacted that would force developers to apply setbacks to all tall buildings.
New York City’s Empire State Building and Chrysler Building are excellent examples of setback design, as well as examples of the esthetic beauty of the art deco structures of that time.
Not only were setbacks desirable but, from an engineering point of view, they helped to diminish the harsh winds that tall buildings were subjected to.
Twisting
Shanghai Tower (right). Photo by qi xna on Unsplash
Spiraling skyscrapers are becoming more popular. Not just for their aesthetic appeal, but also because of their ability to reduce wind vortexes by up to 24%.
For the Shangai Tower, this resulted in a reduction of $58 million that the developers did not have to add to buttress the building.
Even more, aesthetically pleasing is the 1,417-foot tall Diamond Tower in Jeddah, Saudi Arabia. If that’s not intriguing enough, there is the 1,273-foot Dubai Tower that not only twists but also rotates 360 degrees. Built by Italian/Israeli architect David Fisher of Dynamic Architecture, the building gives spectators and residents alike an ever-changing view of the Dubai skyline.
The Willis Tower in Chicago is an excellent example of a building that employs the tubular method for addressing wind forces.
This super tall consists of a collection of nine tubes supporting each other, subsequently buttressing the building to fight off the winds more than if it was just one straight up-and-down structure.
Additionally, since they level off at different heights, the wind forces are inherently disrupted.
Cutout
A less used method but efficient nonetheless. The wind is allowed to pass through specific areas of a building. which reduces the wind loads on the building. Below is an animation demonstrating how the building negotiates the wind forces using cutouts on various floors.
When employing the cutout wind method, other methods of wind optimization are used along with it. New York’s 432 Park Ave makes use of this system. Additionally, the building uses the tuned mass damper system as described in the next section.
Tuned Mass Damper (TMD) (AKA harmonic absorber)
Tuned Mass Damper illustration for Taipei 101
Large, heavy dampers, usually near the top of the building compensate for building vibrations, such as high winds. Similar to a pendulum that sways back and forth, these dampers will move against the wind thereby stabilizing the building.
In technical terms, the mass damper is designed to work in harmony with the oscillation frequency of the building from the wind, thereby reducing the overall sway of the structure.
Combination of the Above
Many times, a multiple of these strategies are used to tackle the vortices, and in so doing, they can be very effective in taming the wind.
Constructing the Superstructure
The superstructure is the actual building, more specifically, it is the framework that connects the foundation to the roof, and this is where the CAD model is pertinent. The CAD model will help to identify the best location for the support columns, known as the centroid.
Engineers will select the most economical material and size of steel for these columns. They must also ensure that the columns are spaced far enough to resist both wind and potential seismic forces. Consideration will go into the type of concrete material and the size of the floor slabs, based on how much weight the slabs must support.
They must also consider the thickness of the slabs based on the amount of deflection allowed by the building codes, but we’ll leave the details of these considerations to another article that provides the specifics of these components.
Structural Engineering in a Nutshell
Watch this video which lays out the concepts of the engineering techniques required to build a tall building.
Summary
The engineering behind the making of skyscrapers is a complex and lengthy journey. When engineers design a supertall, they must consider many different aspects of the project. They must select materials that can withstand the forces of nature such as high winds, heavy precipitation, and even earthquakes.
They must also ensure that the building is structurally sound. In today’s skyscrapers, you can rest assured that the hard work and dedication that was put into each of these buildings by the architects, engineers, and construction workers make these buildings sound and secure.
The power of steam has had a significant impact on the history of humankind and the concept of how they work is fascinating. From the Industrial Revolution to the modern day, steam engines have been used to power the world in a variety of ways.
In this article, we’ll take an in-depth look at how steam engines work and the impact they’ve had on history. We’ll explore the science behind how steam is generated and how its energy is used to power machines.
We’ll also discuss the various applications, from powering locomotives to generating electricity. By the end of this article, you’ll have a comprehensive understanding of the science, history, and impact of steam engines.
History
SS Savannah. Half steamboat, half sailboat.
The first steam engines were used in the mid-17th century to pump water out of gold and silver mines. The first steam-powered ship, the SS Savannah was launched in 1819. However, it wasn’t until the mid-19th century that steam engines were widely used for industrial production.
While the first steam-powered locomotive was built in 1829, it wasn’t until the 1850s that railroads began to widely use them.
The Industrial Revolution was a time of incredible innovation and growth in the mid-19th century. The invention of the steam engine during this period greatly contributed to its growth.
Many of the machines and products we use every day were first developed during this period. Engines powered by steam were used to power textile mills and other industries. They drove a variety of machines, from looms to cranes. They were used to power the bellows (furnaces) for forges. Forges were used to make swords, knives, agricultural tools, and many other metal products.
How Steam is Generated
Before we can discuss how steam engines work, we first need to understand how the energy source for these engines is produced.
Boiling Point
Steam is the result of water being heated past its boiling point. When water is heated past 212° F (100°C), it turns into a gas, which is steam. The result is that the volume of steam (the amount of space that a substance or object occupies)is always greater than that of water; therefore, it will want to push its way out of the container if the container is not large enough to hold it.
This is why it is recommended not to place aerosol spray cans near heating sources. The spray is in liquid form but if it is near a heating source and the liquid starts to boil and turns into steam, there is a chance that the can will explode since the steam needs to expand.
The mechanism for Boiling the Water
Boilers are what are used to boil the water into steam. There are several types of boilers, but they all have one thing in common: they are enclosed vessels that contain water.
Steam boilers are used to power a variety of machines. The most well-known application was to power locomotives. As we mentioned above, when water is converted into steam, the steam will push its way out and if this force of pressure is harnessed in a way that it can be regulated, it becomes a source of energy that can become very useful.
In the steam engine, there are openings in the boiler to let the steam out, and when this steam comes out, it becomes a force pressure on which anything it touches will have an effect; in other words, if there is a wheel barrel next to where the steam is thrust out, it will propel the wheel barrel quite a distance.
Enter the Piston
Steam enters the cylinder (red pipe) and pushes the piston down. Steam stops and the piston moves back up. This cycle repeats itself until the process is stopped. Animation: Wikimedia Public Domain.
If the steam is connected to a piston, which is a cylindrical body inside a container (noted in green), usually metal that slides down when a force hits it (in this case steam), it will move, and if another object is connected to the piston, (where the white hole is at the bottom) such as a wheel, the piston will then move the wheel.
Now picture a row of pistons set up to move when the power of the steam hits on it, it can then move any number of wheels.
Pistons have an additional feature and that is their ability to move back up to the top of their cylinder once the force of the steam stops, and if this process is regulated so that the steam comes out at regular intervals, the wheels that the pistons are connected to will keep on rolling.
This is how steam locomotives work, not to mention steamboats and machinery in factories as you will read further on.
Steam engines are also used to generate electricity in power plants. When it is generated in a boiler and then forced through a turbine, it spins a wheel, which is connected to a generator. This generates electrical energy via electromagnetism (the creation of electric current by spinning magnets).
Locomotives were all the rage in the 19th and early 20th centuries and it was the most common application of steam engines during the Industrial Revolution.
They were used to pull freight and passenger trains and were especially useful for transporting goods over long distances since they were much more efficient than horse-drawn wagons.
Additionally, these trains were able to climb steep hills.
Ships
Many people think that steam engines came into widespread use on land, but they were also used to power ships. Ships were initially powered by wind and muscle power, but when the power of steam came along, they were used to power commercial ships in the early 1800s.
Steam engines were used in larger ships, such as steamships, which sailed between Europe and the United States. A perfect example is the Titanic. Although it came to a tragic end it was a giant and beautiful steamship that traveled across the Atlantic and powered everything from the kitchen cooking appliances to the giant pistons that moved the ship.
Automotive
Steam engines are used to power automobiles in two ways. Some steam cars use a steam engine to power the wheels. Others use steam to generate electricity that can be used to power an electric motor. Steam cars have a long history dating back to the early 1900s. They were used throughout the 20th century until they were largely replaced by internal combustion engines.
Factories
Another common use was to power factories. They were used to mass-produce goods, and the engines were used to power the machinery that was used to produce goods, such as lathes, looms, and other industrial machinery.
Modern-Day Uses of Steam Engines
As we progress into the 21st century, the employment of steam is still being used for various purposes. They are often used in remote areas, such as deserts and mountains, where electrical grids are not available. In these areas, steam engines generate electricity.
Power Generation
Electrical power plants are no exception and there are still power grids in the US and around the world that use steam to generate electricity. The steam used in a power plant is usually generated by burning coal or natural gas, which then drives the pumps that transport water uphill.
Conclusion
The impact of steam engines on history can’t be overstated. It is estimated that steam engines powered about 90% of the world’s industrial production around the start of the 20th century, which greatly contributed to the growth of many industries.
The textile industry, for instance, could not have grown to its current size without the use of steam. They were used to power the looms that were necessary for producing textiles on a large scale. Steam engines also helped transform the iron and steel industry. Before the invention of steam engines, the iron was produced in small forges. Once steam engines were used in forges, iron production could be carried out at larger scales. It also contributed to the growth of agriculture by powering irrigation systems.
Illustration of a Black Hole Photo: iStock. Elements of this image furnished by NASA.
Leave It Up to James Webb
In July 2023, astronomers discovered the most distant active supermassive black hole to date. This gravitational phenomenon is located in galaxy CEERS 1019, which is seen as it was when the universe was just 570 million years old. This is only 100 million years after the Big Bang, making it the earliest active supermassive black hole ever observed.
The Most Distant One – CEERS 1019
The black hole is also one of the least massive seen in the early universe, measuring the equivalent of about 9 million suns. This is much smaller than the supermassive black holes that are typically found in the centers of galaxies, which can weigh billions or even trillions of suns.
The discovery of this early black hole is baffling astronomers since it has been concluded that supermassive black holes form from the gravitational collapse of massive stars, but in this case, is not clear how a star could have formed so early in the universe and grown to be so massive in such a short time.
This raises questions about the evolution of galaxies. It is thought that supermassive black holes play a role in the formation and evolution of galaxies, but it is not clear how. The discovery of this black hole suggests that supermassive black holes may have been more common in the early universe than previously thought and that they may have played a more important role in the evolution of galaxies than we had realized.
Hopefully, it is a case where we have to back to the drawing board, but this black hole is definitely something where additional thought needs to be done where there may be other entities at work here that we just don’t know about – yet!
The Big One
Although the James Webb telescope is bringing never-before-seen wonders to our eyes, the famous Hubble is not without merit.
300 million light-years away at the heart of the Coma Cluster lies one of the largest black holes ever discovered. The Coma Cluster is a large collection of over 1,000 galaxies, which is quite amazing in its own right.
NGC 4889 shines as the largest and brightest galaxy and its supermassive black hole is breaking all kinds of records. In comparison, the mass of the black hole at the center of our Milky Way galaxy is about four million times that of our Sun. The mass of the black hole at the center of NGC 4889 is around twenty-one billion times the mass of our Sun.
Early in its life, astronomers would classify the black hole as a quasar. A quasar is a massive and remote celestial object, releasing large amounts of energy. It is believed that quasars themselves contain massive black holes and are just a stage in the evolution of some galaxies.
At this time as a quasar, NGC 4889’s black hole was devouring all the stars, gas, and galactic dust in its path. This massive meal only fueled the black hole into forming an accretion disc that orbits the black hole and accelerates the black hole’s gravitational pull. The galactic dinner is heated up to millions of degrees and expelled around the black hole up to a thousand times the energy output of our own Milky Way.
Once the supermassive black hole’s appetite was filled and the lavish meal finished, the black hole fell into a deep and dormant state that it is currently in. The environment of the surrounding galaxy is so peaceful that stars are forming from the remaining gas that’s calmly orbiting the black hole.
Quasars and black holes continue to remain mysterious objects to astronomers and scientists. Luckily with new images thanks to various telescopes around the world astronomers can further their knowledge of these objects. Even though it is impossible to directly see a black hole since light can’t escape its gravitational pull, the mass of a black hole can still be determined. Astronomers in Hawaii at the W. M. Observatory and the Gemini North Telescope measured the velocity of stars moving around the center of NG 4889. These instruments determined the massive supermassive black hole.
NASA was already working on a new venture for a more efficient spacecraft that they could reuse instead of relying on the disposable rockets that cost them billions of dollars to build each time.
This idea of a reusable rocket that could launch astronauts into space, but dock and land like an airplane were well-accepted for future space travel.
Enter the Space Shuttle Program
Early space shuttle concept. Photo: Wikimedia Public Domain
In 1972, President Nixon announced that NASA would develop a reusable space transportation system (STS). They decided that the shuttle would consist of an orbiter attached to solid rocket boosters and an external fuel tank. This design was considered safer and more cost-effective.
One of the first obstacles was to design a spacecraft that didn’t use ablative heat shields, which subsequently burned up each time the shuttle re-entered the Earth’s atmosphere.
For the shuttle to be reusable, a different strategy would have to be initiated. The designers came up with an idea to overlay the craft with insulating ceramic tiles that would absorb the heat of reentry, without causing any danger to the astronauts.
The First Flights
The first of four test flights began in 1981, leading to operational flights starting in 1982. They were used on a total of 135 missions from 1981 to 2011. The launchpad used was the Kennedy Space Center in Florida.
Like the previous Saturn V rocket, the Space Shuttle had different components of its own, which included the Orbiter Vehicle (OV), a pair of recoverable solid rocket boosters (SRBs), and the expendable external tank (ET), containing liquid hydrogen and liquid oxygen as fuel.
The Shuttle was launched vertically, the same as any rocket in its category would launch, using the two SRBs to jettison it. The SRBs operated in a parallel fashion by utilizing the fuel from the ET.
Once the mission had been completed, the shuttle would land similar to a jet aircraft on the runway of the Shuttle Landing Facility of KSC or Rogers Dry Lake in Edwards Air Force Base, California. After landing at the base, the orbiter was then flown back to the KSC on the Shuttle Carrier Aircraft, which was a specially modified Boeing 747.
Tragedy Hits
Although the accomplishments that the shuttle program has achieved are beyond expectations, there were two unfortunate events during its time.
Challenger January 28, 1986
Shortly after liftoff, the Space Shuttle Challenger exploded f the U.S. space shuttle orbiter Challenger, claiming the lives of seven astronauts.
Among those who were lost were teacher-in-space Christa McAuliffe, commander Francis (Dick) Scobee, pilot Michael Smith, mission specialists Ellison Onizuka, Judith Resnik, and Ronald McNair, and Hughes Aircraft engineer Gregory Jarvis.
The crew of Space Shuttle mission STS-51-L poses for their official portrait on November 15, 1985. In the back row from left to right: are Ellison S. Onizuka, Sharon Christa McAuliffe, Greg Jarvis, and Judy Resnik. In the front row from left to right: Michael J. Smith, Dick Scobee, and Ron McNair. Photo: Wikimedia Public Domain
Columbia Feb 1, 2003
It was the final mission of Columbia. Seven crew members lost their lives when the shuttle burned up over the state of Texas during its reentry on Feb 1, 2003.
The STS-107 crew included, from the left, Mission Specialist David Brown, Commander Rick Husband, Mission Specialists Laurel Clark, Kalpana Chawla, and Michael Anderson, Pilot William McCool, and Payload Specialist Ilan Ramon. (NASA photo. via Wikipedia)
No, we’re not talking about the TV show. We are talking about the real thing. A phenomenon that has baffled scientists and astronomers for millenniums.
Bang Zoom!
It’s the Big Bang that has originated as a pinpoint (yes that small!) of intensely hot, immensely dense energy that appeared out of apparently nowhere.
It’s the Little Things
If we may steal an excerpt from the bible – “In the beginning, God created the heavens and the Earth”. Now allow us to extrapolate this scientifically to mean that there existed an incomprehensively immeasurable point that at some point in time (we say time here as a reference, but it didn’t exist yet), this immensely tiny entity planted the seed of what we call the universe.
And the Single Things
The origin of the Big Bang is where this tiny region, called a singularity, is where the density of matter, or more technically described as the curvature of spacetime, becomes infinite.
Confused? You’re not alone, so let’s try defining it another way. A singularity represents the phenomenon that the pull of gravity becomes so strong that nothing, not even light, can escape it.
Still confused? How about this explanation? A singularity is where all matter and energy are concentrated into one single point thanks to the force of gravity.
We have seen this occurrence with the existence of black holes.
NASA illustration of the Big Bang Photo: NASA
Be Cool
As this hot area began to cool down, the first photons, namely, quarks and leptons condensed out of the fizzing vacuum, like a mist on a cold window to form a quark-gluon plasma sea. (For an illustration of how small these entities are, visit The Scale of the Universe and keep cruising down through the world of the micro-universe, until you reach quarks, 10-18 meters in size).
Time Has Arrived But Atom is Nowhere to Be Found
After one-millionth of a second, the quarks combined into hadrons, primarily protons, and neutrons, while vast amounts of matter and antimatter wiped each other out, leaving only a billionth of the original material, along with vast quantities of gamma rays. About a second after the birth of the universe, its temperature dropped enough to crystallize whizzing neutrinos from the photons.
Nucleosynthesis started to materialize, with protons and neutrons joining to form the nuclei of helium, deuterium, and lithium.
Minutes later, matter consisted simply of three parts hydrogen to one part helium. The universe was expanding incredibly fast, and after a few hours, there was no longer the density of neutrons to allow any heavier nuclei to form.
Fast Forward a Few Thousand Years
When the universe was an estimated 377,000 years old, it finally became cool enough for electrons to settle into orbits around atomic nuclei.
For the next 100 million years everything remained dark as the vast ionized clouds of hydrogen and helium expanded. Eventually, however, the photons were set free from the plasma, and the infant universe was unveiled in all its glory.
The first bodies to emerge from the chaos of the early universe were quasars. The most powerful and luminous objects in the universe, early active galaxies, built around young supermassive black holes, forming slight inconsistencies in the otherwise uniform expansion of the universe.
Soon after, inside and outside of these protogalaxies, Nebulas which are large clouds of the ingredients of hydrogen and helium create stars and planets that start to explode into life. After they exploded, they seeded newly minted elements into the mix.
And the Cycle of Life Begins
For the next 500,000 years, until the universe’s first billionth birthday, quasars and early stars hatched, lived, died, and were recycling earlier generations and pouring out intense radiation that re-ionized their surroundings. Ninety-nine percent of all matter in the universe remains in the form of fizzy ionized plasma from this time.
Electric generators are the opposite of electric motors, but they work on the same concept. Whereby an electric motor uses an electric current to create a magnetic field, a generator uses a magnetic field to induce an electric current. If you read our article on electric motors, then this should sound very familiar. The process is only reversed.
The current that is produced flows through a conductor which is usually a wire, but it can also be a metal plate. The output of the current is then used to power anything from a small device (e.g. a lamp or computer) to an entire town or city.
What They are Used For
Generators are used to create electricity which then powers homes and businesses. They can be powered by either an electromagnet or a permanent magnet. The type of generator you use will determine how much electricity you can generate.
They are often used to provide backup power in case of a power outage, and they are also used in many portable applications such as camping and RVing. Just about all emergency facilities have backup power, such as hospitals.
In some cases, generators can also be used to supplement the main power source, providing additional power during high-demand periods.
The most common power sources are fuels such as coal, natural gas, or oil.
How Does an Electric Generator Create Energy?
When the generator is turned on, its moving parts create a magnetic field, producing an electric current. (Remember with electric motors, an electric current is produced that provides a magnetic field. This is the opposite of what generators do.) The current flows through wires to an external circuit, where it can be used to power electric devices. In this way, an electric generator converts mechanical energy into electrical energy.
What are the different types of electric generators available on the market today?
The most common type uses a combustion engine to generate electricity. These engines can be powered by gasoline, diesel, natural gas, or propane.
Another type is the steam turbine, which uses steam to power a turbine that generates electricity. Steam turbines can be powered by coal, nuclear reactors, or solar thermal power plants.
The third type of generator is the hydroelectric generator, which uses water to power a turbine that generates electricity. Hydroelectric generators can be powered by waterfalls, dams, or river currents. The Niagara Project is a perfect example of the delivery of electricity via hydroelectric generators.
Wind turbines spin which produces a magnetic field which then produces electricity. Photo by Gonz DDL on Unsplash
The fourth type of generator is the wind turbine, which uses wind to power a turbine that generates electricity, but there must be enough wind for the proper amount of electricity to be produced.
Wind turbines can be used in both onshore and offshore locations.
How Can You Choose the Right Electric Generator for Your Needs and Budget?
With so many different brands, models, and features to choose from, it’s hard to know where to start. However, by considering a few factors, you can narrow down your options and find the perfect generator for your needs and budget.
First, decide what type of generator you need. For example, if you only need power for occasional use, such as during a power outage, a portable generator may be sufficient.
However, if you need a constant supply of electricity, such as for a construction site or an RV, a stationary generator would be a better choice.
Next, consider how much power you will need. For most applications, a small generator that produces around 2,000 watts will suffice.
However, if you need to run large appliances or multiple devices at once, you’ll need a more powerful model. Finally, compare prices to find the best value for your money. Be sure to factor in the cost of fuel and maintenance when making your decision. By considering these factors, you can find the perfect electric generator for your needs and budget.
Important Safety Tips
First, always read the manufacturer’s instructions carefully before operating the generator. This will help you to understand how the generator works and what safety measures need to be taken.
Next, make sure that the generator is properly grounded before use. This will help to prevent electrical shock. Finally, never operate the generator near flammable materials or in enclosed spaces, as this can create a fire hazard.
By following these simple safety tips, you can help to ensure that your experience with an electric generator is safe and enjoyable.
When an electric current runs through a wire, a magnetic field is produced and when there is a magnetic field, metallic elements become attracted to it. This is the concept behind the workings of an electric motor.
If we can maintain these elements to move towards the magnetic field and away from it at an ongoing, continuous rate, we can have a device that is constantly spinning.
If we attach something to the part of the device that is constantly spinning, such as a glass plate in the microwave, we have harnessed the power of converting electrical energy into mechanical energy, or more specifically, we have created an electric motor.
What Devices Use Electric Motors?
When you use an electric razor, toothbrush, fan, or vacuum cleaner, you are using an electric motor. Let’s through the inner workings of your car also. That’s probably no surprise, but how about this: washing machines, refrigerators, microwaves, your computer, and even your smartphone!
Confused? Don’t be. Something is needed to operate the refrigerator’s compressor. If there is a mechanical hard drive in your computer, then there is a small motor that turns the disk. And microwaves? Well, something must be spinning that glass plate around, right?
And your electric cars (if you have one). They have motors, which are used to spin the tires as you drive, among other things.
The bottom line is you probably go about your day using some device that uses an electric motor. So now that we know how our lifestyles are affected by these devices, let’s delve into how these motors work.
The Working of an Electric Motor
First, let us focus on the magnetic field that causes the components within the motor to constantly spin.
How is the magnetic field created? Our article on magnetic fields explains this, but in a nutshell, if we connect a wire to a battery, the electrons of each of the atoms will move toward the positive pole of the battery. If we wrap the wire around a metal rod, the magnetic field intensifies.
Inside of an electric motor. Photo: iStock
The Initial Stage
The motor is designed so that the magnetic poles of a rod, called a rotor are always facing the same polarity of a stationary magnet, called a stator, causing the rotor to spin around.
For example, when electricity is turned on, the polarity of one side of the rotor, let’s say the north side is initially facing the north side of the stator, so there will be that repelling effect, causing the rotor to spin in the other direction.
The Next Stage
Well, that initial stage works just as it should because like poles repel each other, but that’s it. Then it stops, so for the rotor to keep spinning, there has to be a mechanism that will cause the poles to reverse continuously.
That is the job of the commutator. This entity keeps reversing the path of the electrons so that the poles are always repelling one another and consequently, keeps the rotor spinning.
Key Parts of an Electric Motor
Let’s review the parts of the motor:
Stator – The stationary part of the motor that creates the magnetic field that causes the rotor to spin. The stator is found in between two pieces of copper that conduct electricity.
Rotor – The rotating part of the motor is placed within the magnetic field.
Shaft – The motor shaft connects the rotor to the stator and is used to power the equipment or machinery.
Commutator – The device that reverses the polarity of the rotor. Like reversing a battery at every spin so that the electrons change course.
Fan – The fan is used to create airflow and increase the efficiency of a motor.
Final Words
Electric motors are all around us. They are a safe, efficient, and reliable way to power machinery and equipment. They are available in a range of sizes, voltages, and designs and can be powered by a wide range of energy sources, including fossil fuels and renewable energy sources like solar or wind.
Depiction of a wire wrapped around a nail and connected to a battery, creating a complete circuit, resulting in the creation of an electromagnetic. When electrons start to run through the wire (from one end of the battery to the other), a magnetic field is produced and the nail is magnetized, consequently, the paper clips are attracted to the nail. If the power shuts off, the paper clips will no longer have that attraction. Photo: iStock.
Let’s Start with a Piece of Metal
Let’s use iron for example. Touch it with another piece of iron and what happens? Nothing! Now take a bare wire, copper preferred. Wrap the copper wire around one of the pieces of iron and what happens? Still nothing!
Now grab both ends of the copper wire and connect it to a battery. What happens? Still nothing – at least nothing noticeable that the naked eye can see!
What is happening when the wires connect to the battery (called a circuit) is that the electrons were random before the circuit was completed and they straightened out, like a row of marching soldiers after the circuit is complete.
These marching electrons will point and move towards the pole ( polarity) of the battery it is connected to. Now let’s get a little more technically correct and call these marching electrons an electric current, and as these electrons (current) are moving through the wire, a magnetic field is produced.
When There is Electric Current, There is a Magnetic Field
Left: Iron bar with wire wrapped around it (coil) and iron filings nearby laying stationary because the wires are not a complete circuit (connected to the battery). Right: Same configuration but with the circuit complete and iron fillings are then attracted to it. Photo: iStock
But Just What is This Magnetic Field?
If we pick up the other piece of iron (which does not have the copper wire around it) and place it near the iron piece that has the wire wrapped (and thus the electric current), that isolated piece of iron suddenly moves toward the electrified one.
The reason why the iron pieces attract each other is that the iron piece with the copper wire wrapped around it (called a coil) becomes magnetic. And so, we have just created an electromagnet!
For the video below, you might want to put your thinking caps on as it explains pretty well how electromagnetic forces are derived (hint: when electrons move through a wire). We suggest those that who are in school and/or have an absorption for learning continue to this video.
For those that would like to bypass such items as Maxwell’s equations and just want a cheat sheet of what is the criteria for an electromagnetic field, see our summary below.
How Electromagnets are Made
An electromagnet can be made out of any type of metal, but iron and nickel are the ones most often used. Nickel magnets are stronger than iron magnets, but iron is cheaper.
Iron is found in most scrap yards, or you can buy it from a hardware store. The first step in making an electromagnet is to create a wire that is wrapped with a coil of metal several times. This is known as an electromagnet coil. The coil has to be wrapped around a core, which is made out of a non-magnetic material.
The Magnetic Field
A permanent magnet has the same properties as an electromagnet but without the current. Image by Francesco Bovolin from Pixabay
The electromagnetic field is the region of energy surrounding a magnet. The magnetic field is perpendicular to the path where the electrons flow.
Why are Electromagnets Important?
Electromagnets are important because they can be used to power items and devices that are used by us every day. Motors and generators are just two examples. They are also used in toys, as a way of moving things around in a car or even to move things in a factory.
They are also useful because they’re easily controllable. If you want to turn the electromagnet off, you simply turn off the electric current running through it. If you want to turn it back on, you can simply turn it back on again.
Types of Magnets
There are two types: temporary and permanent. Temporary magnets are only magnetic while electricity is running through them. Permanent magnets remain magnetic no matter what happens. This is because these magnets are not electrified. An example is the ones stuck to your fridge or another metal surface.
Conclusion
Magnetism is created when electrons are in movement. In a practical sense, this means that if you connect a wire to a battery (power source), electrons will move from the negative pole to the positive pole of the battery.
When this happens, a force is created in addition to the electrical force, which is the magnetic force. This magnetic force ‘pushes’ perpendicular to electrical force (current), so any metal that has magnetic properties will be attracted to this force and move towards it accordingly.
The magnetic force can be strengthened by any of the following criteria.
Take the straight wire and curl it around the medium, usually an iron bar. The result is called a coil.
Wiring the coil more will cause the magnetic field to strengthen.
Increasing the current; that is, increasing the speed at which the electrons travel through the coiled wire will also strengthen the magnetic field.
The practical applications of electromagnets are the ability to cause an entity to move because of this force, such as what happens inside a motor.
