unit (solar system)

8/14/2019 Unit (Solar System)

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Solar System

The Solar System consists of the Sun and its planetary system of eight planets, their moons, and other

non-stellar objects. It formed 4.6 billion years ago from the gravitational collapse of a giant molecular

cloud. The vast majority of the system's mass is in the Sun, with most of the remaining mass contained

in Jupiter. The four smaller inner planets, Mercury, Venus, Earth and Mars, also called the terrestrial

planets, are primarily composed of rock and metal. The four outer planets, called the gas giants, are

substantially more massive than the terrestrials. The two largest, Jupiter and Saturn, are composed

mainly of hydrogen and helium; the two outermost planets, Uranus and Neptune, are composed largely

of substances with relatively high melting points (compared with hydrogen and helium), called ices, such

as water, ammonia and methane, and are often referred to separately as "ice giants". All planets have

almost circular orbits that lie within a nearly flat disc called the ecliptic plane.

From the perspective we get on Earth, our planet appears to be big and sturdy with an endless ocean of

air. From space, astronauts often get the impression that the Earth is small with a thin, fragile layer of

atmosphere. For a space traveler, the distinguishing Earth features are the blue waters, brown andgreen land masses and white clouds set against a black background. Many dream of traveling in space

and viewing the wonders of the universe. In reality all of us are space travelers. Our spaceship is the

planet Earth, traveling at the speed of 108,000 kilometers (67,000 miles) an hour.

Earth is the 3rd planet from the Sun at a distance of about 150 million kilometers (93.2 million miles). It

takes 365.256 days for the Earth to travel around the Sun and 23.9345 hours for the Earth rotate a

complete revolution. It has a diameter of 12,756 kilometers (7,973 miles), only a few hundred

kilometers larger than that of Venus. Our atmosphere is composed of 78 percent nitrogen, 21 percent

oxygen and 1 percent other constituents. Earth is the only planet in the solar system known to harbor

life. Our planet's rapid spin and molten nickel-iron core give rise to an extensive magnetic field, which,

along with the atmosphere, shields us from nearly all of the harmful radiation coming from the Sun and

other stars. Earth's atmosphere protects us from meteors, most of which burn up before they can strike

the surface. rom our journeys into space, we have learned much about our home planet. The first

American satellite, Explorer 1, discovered an intense radiation zone, now called the Van Allen radiation

belts. This layer is formed from rapidly moving charged particles that are trapped by the Earth's

magnetic field in a doughnut-shaped region surrounding the equator. Other findings from satellites

show that our planet's magnetic field is distorted into a tear-drop shape by the solar wind. We also now

know that our wispy upper atmosphere, once believed calm and uneventful, seethes with activity --

swelling by day and contracting by night. Affected by changes in solar activity, the upper atmosphere

contributes to weather and climate on Earth.

Besides affecting Earth's weather, solar activity gives rise to a dramatic visual phenomenon in our

atmosphere. When charged particles from the solar wind become trapped in Earth's magnetic field, they

collide with air molecules above our planet's magnetic poles. These air molecules then begin to glow

and are known as the auroras or the northern and southern lights.


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Earth Statistics

Mass (kg) 5.976e+24

Mass (Earth = 1) 1.0000e+00

Equatorial radius (km) 6,378.14

Equatorial radius (Earth = 1) 1.0000e+00

Mean density (gm/cm^3) 5.515

Mean distance from the Sun (km) 149,600,000

Mean distance from the Sun (Earth = 1) 1.0000

Rotational period (days) 0.99727

Rotational period (hours) 23.9345

Orbital period (days) 365.256

Mean orbital velocity (km/sec) 29.79

Orbital eccentricity 0.0167

Tilt of axis (degrees) 23.45

Orbital inclination (degrees) 0.000

Equatorial escape velocity (km/sec) 11.18

Equatorial surface gravity (m/sec^2) 9.78

Visual geometric albedo 0.37

Mean surface temperature 15C

Atmospheric pressure (bars) 1.013

Atmospheric composition

Nitrogen

Oxygen

Other

77%

21%

2%


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Renewable source of energy

In the past century, it has been seen that the consumption of non-renewable sources of energy has

caused more environmental damage than any other human activity. Electricity generated from fossil

fuels such as coal and crude oil has led to high concentrations of harmful gases in the atmosphere. This

has in turn led to many problems being faced today such as ozone depletion and global warming.

Vehicular pollution has also been a major problem. Therefore, alternative sources of energy have

become very important and relevant to todays world. These sources, such as the sun and wind, can

never be exhausted and therefore are called renewable. They cause less emissions and are available

locally. Their use can, to a large extent, reduce chemical, radioactive, and thermal pollution. They stand

out as a viable source of clean and limitless energy. These are also known as non-conventional sources

of energy. Most of the renewable sources of energy are fairly non-polluting and considered clean

though biomass, a renewable source, is a major polluter indoors.

What are these alternative sources of energy

Under the category of renewable energy or non-conventional energy are such sources as the sun, wind,

water, agricultural residue, firewood, and animal dung. The non-renewable sources are the fossil fuels

such as coal, crude oil, and natural gas. Energy generated from the sun is known as solar energy. Hydel is

the energy derived from water. Biomassfirewood, animal dung, biodegradable waste from cities and

crop residues- is a source of energy when it is burnt. Geothermal energy is derived from hot dry rocks,

magma, hot water springs, natural geysers, etc. Ocean thermal is energy derived from waves and also

from tidal waves. Through the method of co-generation a cleaner and less polluting form of energy is

being generated. Fuel cells are also being used as cleaner energy source. In India a number of initiatives

have been taken. A good example is the model village of Ralegaon Siddhi. When you burn a piece of

wood it turns into ash. Can you use this ash to again light a fire? No, You cannot do this. This is exactly

what happens to the non renewable sources of energy such as coal, natural gas and oil. Once you burn

them they cannot be reused. Other than this it also causes extensive damage to the environment.

Renewable energy resources, such as wind, solar and hydropower, offer clean alternatives to fossil fuels.

They produce little or no pollution or greenhouse gases, and they will never run out.

1. Solar Energy

The sun is our most powerful source of energy. Sunlight, or solar energy, can be used for heating,

lighting and cooling homes and other buildings, generating electricity, water heating, and a variety of

industrial processes. Most forms of renewable energy come either directly or indirectly from the sun.

For example, heat from the sun causes the wind to blow, contributes to the growth of trees and other

plants that are used for biomass energy, and plays an essential role in the cycle of evaporation and

precipitation that makes hydropower possible.


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2. Wind Energy

Wind is the movement of air that occurs when warm air rises and cooler air rushes in to replace it. The

energy of the wind has been used for centuries to sail ships and drive windmills that grind grain. Today,

wind energy is captured by wind turbines and used to generate electricity.


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3. Hydropower

Water flowing downstream is a powerful force. Water is a renewable resource, constantly recharged by

the global cycle of evaporation and precipitation. The heat of the sun causes water in lakes and oceans

to evaporate and form clouds. The water then falls back to Earth as rain or snow, and drains into rivers

and streams that flow back to the ocean. Flowing water can be used to power water wheels that drive

mechanical processes. And captured by turbines and generators, like those housed at many dams

around the world, the energy of flowing water can be used to generate electricity.

4. Biomass Energy

Biomass has been an important source of energy ever since people first began burning wood to cook

food and warm themselves against the winter chill. Wood is still the most common source of biomass

energy, but other sources of biomass energy include food crops, grasses and other plants, agricultural

and forestry waste and residue, organic components from municipal and industrial wastes, even

methane gas harvested from community landfills. Biomass can be used to produce electricity and as fuel

for transportation, or to manufacture products that would otherwise require the use of non-renewable

fossil fuels.

5. Hydrogen

Hydrogen has tremendous potential as a fuel and energy source, but the technology needed to realize

that potential is still in the early stages. Hydrogen is the most common element on Earthfor example,

water is two-thirds hydrogenbut in nature it is always found in combination with other elements.

Once separated from other elements, hydrogen can be used to power vehicles, replace natural gas for

heating and cooking, and to generate electricity.


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6. Geothermal Energy

The heat inside the Earth produces steam and hot water that can be used to power generators and

produce electricity, or for other applications such as home heating and power generation for industry.

Geothermal energy can be drawn from deep underground reservoirs by drilling, or from other

geothermal reservoirs closer to the surface.

7. Ocean Energy

The ocean provides several forms of renewable energy, and each one is driven by different forces.

Energy from ocean waves and tides can be harnessed to generate electricity, and ocean thermal

energyfrom the heat stored in sea watercan also be converted to electricity. Using current

technologies, most ocean energy is not cost-effective compared to other renewable energy sources, but

the ocean remains and important potential energy source for the future.

Sustainable Architecture (http://www.eslarp.uiuc.edu/arch/ARCH371-

F99/groups/k/hannover.html)

On Earth Day, April 22, 1970, the world voiced their concern about the population growth and the

exponential increase in industrial activity. Concern was heightened even more when supplies of fossil

fuels from the Middle East were cut back and energy prices increased during the 70's. People began to

search for ways of protecting the environment and using less energy in their buildings. The country

became tired of the long lines at gas station pumps, uncontrolled pollution, and environmentally

damaging materials. A whole new emphasis was placed on using the free natural resources of the earth,

as well as recycling the resources already exploited. New studies began to show the taxing effects of

pollution, and more importantly, that there was still time to do something about it. Lobbyists began

instituting laws limiting pollution output and even banning some chemicals and industrial products. The

world quickly learned that "an ounce of prevention is worth a pound of cure." While properly disposing

of hazardous materials and filtering smoke from power plants and factories was a costly effort, it was

undoubtedly cheaper than cleaning up the environment later.

While the clean-burning fuels and electric cars were (and are) yet to become economically sound, one of

the easiest places to experiment with sustainability was within the living space. Using natural building

materials such as wood and stone is much more environmentally sound than steel and concrete.Building with recycled elements saves landfills from untold tons of garbage every year. Solar heating

and passive cooling cuts energy bills down to pennies on the dollar. Indeed, sustainability was not only

cost efficient, but allowed buildings to become part of the environment, rather than stick out from it.

Sustainability also became known as "green" architecture.

What is "Sustainable Architecture?"


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Eco-housing, green development, sustainable design -- environmentally sound housing has as many

names as it has definitions, but the Rocky Mountain Institute, in its "Primer on Sustainable Building",

flexibly describes this new kind of architecture as "taking less from the Earth and giving more to people."

In practice, "green" housing varies widely. It can range from being energy efficient and using nontoxic

interior finishes to being constructed of recycled materials and completely powered by the sun. Green

building practices offer an opportunity to create environmentally sound and resource-efficient buildings

by using an integrated approach to design. Green buildings promote resource conservation, including

energy efficiency, renewable energy, and water conservation features; consider environmental impacts

and waste minimization; create a healthy and comfortable environment; reduce operation and

maintenance costs; and address issues such as historical preservation, access to public transportation

and other community infrastructure systems. The entire life cycle of the building and its components is

considered, as well as the economic and environmental impact and performance.

Architectural Response to Sustainability

Since the Oil Embargo in the 1970s, there has been an increased awareness in environmental issues.

Some people may look at the loss of non-renewable resources and think automobiles are the main

cause. However, that is not so. It may be suprising to many that the majority of energy depletion

comes from buildings. Half of the non-renewable resources that are used are wasted by buildings and

homes, where as only 25% is used by automobiles . In addition, the United States citizen uses 20 times

more raw materials than the average world citizen. This shock has hit the architectural field hard but

there has been little done to remedy the situation. The idea of sustainable architecture is not new. As

defined by Robert Berkebile, AIA, It is design that improves the quality of life today without diminishing

it for the next generation. However, sustainable architecture is hardly ever used. The lack of green

architecture is a fault of both the client and the architect. It is the architect's responsibility to converse

to the client about sustainability, but most firms do not have the resources in their files to producebeneficial or new ideas about designing sustainable buildings. Also, if an architect does wish to produce

a sustainable building, the client may not want to pay the additional costs it may take to construct, and

is most the time unaware of the benefits. he time has come to educate the clients about design issues

such as sleek does not mean better and a glass wall is not better than a concrete wall. There comes

a time when people have to stop worrying only about the exterior details and start worrying about the

internal ones, "It is time to stop putting the fins on the Cadillac." We as architects have valuable

resources at our disposal that are more than often over looked. In addition, as designers we must

change the standards of construction. We have to stop pulling details and other pre-fabricated building

systems out of catalogues and use our design ability to change the way architecture runs. Architects

must challenge the preconceptions behind building forms. In fact, there is still much to learn fromtraditional vernacular forms.

Principles of Sustainable Architecture

These points are constantly changing, so that they may adapt as our knowledge of the world evolves.


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1. Insist on rights of humanity and nature to co-exist in a healthy, supportive, diverse and sustainable

condition.

2. Recognize interdependence. The elements of human design interact with and depend upon the

natural world, with broad and diverse implications at every scale. Expand design considerations to

recognizing even distant effects.

3. Respect relationships between spirit and matter. Consider all aspects of human settlement including

community, dwelling, industry and trade in terms of existing and evolving connections between spiritual

and material consciousness.

4. Accept responsibility for the consequences of design decisions upon human well-being, the viability of

natural systems and their right to co-exist.

5. Create safe objects of long-term value. Do not burden future generations with requirements for

maintenance or vigilant administration of potential danger due to the careless creation of products,

processes or standards.

6. Eliminate the concept of waste. Evaluate and optimize the full life-cycle of products and processes, to

approach the state of natural systems, in which there is no waste.

7. Rely on natural energy flows. Human designs should, like the living world, derive their creative forces

from perpetual solar income. Incorporate this energy

efficiently and safely for responsible use.

8. Understand the limitations of design. No human creation lasts forever and design does not solve all

problems. Those who create and plan should practice humility in the face of nature. Treat nature as a

model and mentor, not as an inconvenience to be evaded or controlled.

9. Seek constant improvement by the sharing of knowledge. Encourage direct and open communication

between colleagues, patrons, manufacturers and users to link long term sustainable considerations with

ethical responsibility, and re-establish the integral relationship between natural processes and human

activity.

Sustainable Designs

- A compact envelope allows for very little surface area to be exposed to the external environment.

Thus, providing the structure more economical when it comes to heating and cooling.

- The use of a buffer zone between the core (living space) of a building and its exterior walls, such as the

design of a hallway or a laundry room, helps maintain comfortable conditions internally and saves

energy.


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- Wall types are also important. When wind hits a wall it produces a back flow at the base, which if not

sealed properly or if there was a designed opening, filtration into the building will occur. This will cause

much energy loss and a draft inside.

- Using trees in the landscape is a great way to buffer the strong north winds in the winter. Also, a tree

placed on the southern corner of a house allows for cooling in the summer and heating in the winter.

- Numerous wall types are designed to be energy efficient throughout the year. Some examples of walls

are the Trombe wall and water wall, which absorb heat in the winter.

- Passive solar heating is the use of glazed walls in proper locations to allow sunlight to penetrate in the

winter and to be blocked in the summer. This process, if done properly, will allow heating and cooling to

occur during the relative seasons.

- Solar panels, another use of solar energy, is an enhanced product that exploits sunlight to heat and

produce clean energy. Once a mainstream product in the 1970s, solar panel use is minimal because of

their high cost compared to the price of fossil fuel. However, in the long run, solar panels more thanpay for themselves.

- Earth rammed homes (a house whose walls are backfilled with earth) are of great benefit for the

serious economically aware owner. These types of homes use the natural heating and cooling of the

earth to maintain the internal temperature of the house. Though it may be more costly to dig out and

back fill, the electric and heating bill will be very minute compared to the cost to heat and cool an

average home.

Water Collection

Flood water collection, and the pooling of greywater (from sink and bath) would supply a sufficient

amount of water for irrigation purposes. Connecting residential greywater and storm water run-off to a

centralized underground storage basin would reduce the need for clean city water. Collected water

would help to irrigate residential gardens and green spaces. Gardens and green spaces cut down on

neighborhood pollution and save residents money on certain products such as vegetables. This system

however would be a costly one to install, just as the light rail station was, but like the rail station I feel in

the next ten to fifteen years the city will relize its benefits. For this pooling of water to be beneficial

residents would need to develop green spaces which would require greywater only. Areas such as

flower gardens, vegetable gardens, and mini parks are some examples of things which could usegreywater. Also by creating these attractive landscapes residents could save money on products they

would normally buy at the store by growing vegetables such as tomatos, apples, and watermellon.


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Movement of the Sun

Passive solar design is based on utilizing the suns heat energy and its predictable movements through

the seasons.

As the Earth rotates around the sun on its annual cycle, it is tilted at an angle on its vertical axis. Thisimpacts how the suns rays strike various locations on Earth. The Earth is its most extreme tilt at the

winter and summer solstices.

The sun appears to rise in the east and it sets in the west. In actuality, the Earth is rotating on its axis

and around the sun.

Here are pictures thatcompare the suns path on the winter and summer solstices.

A diagram of the suns path on the winterand summer solstices, Courtesy of DOEThis affects how low or high the sun appears in relation to the horizon.In the winter, the sun is relatively

low in the sky with its lowest arc through the sky on the winter solstice, on December 21st

.In the

summer, the sun travels a high path through the sky and is at its highest angle on the summer solstice,

on June 21st

. The sun travels its shortest and lowest arc through the sky on the winter solstice. The low

winter arc allows the suns rays to reach deep into astructure to warm it on a cold winter day. On the

summer solstice, the sun travels its highest and widest arc through the sky. If the building is designed

with anoverhang or some type of blocking mechanism,the sun heat energy will be blocked and thebuilding will stay cool.

The equinox falls on the point between the solstices and indicates the arrival of spring or fall. This

picture shows the suns path throughout the year. The highest arc represents the suns path on

the summer solstice, while the shortest, lowest arc is the suns path on the winter solstice.
http://greenpassivesolar.com/2010/06/winter-summer-sun-solstice-pictures/http://greenpassivesolar.com/2010/06/winter-summer-sun-solstice-pictures/http://greenpassivesolar.com/2010/06/winter-summer-sun-solstice-pictures/http://greenpassivesolar.com/passive-solar/building-characteristics/overhang-solar-control/http://greenpassivesolar.com/passive-solar/building-characteristics/overhang-solar-control/http://greenpassivesolar.com/2010/06/winter-summer-sun-solstice-pictures/


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On each equinox, the sun travels a path that is right in the middleof the path that it travels on

the solstices.

March 21stVernal Equinox

June 21

st

Summer Solstice (highest path)

Sept 21stAutumnal Equinox

Dec 21st

Winter Solstice (lowest path)

Passive solar design uses the predictable movements of the sun to best utilize its energy within the

buildings overall design both for heating and cooling purposes. Many passive solar buildings also

include active solar aspects, such as photovoltaic panels, as shown on the roof in the first diagram

located at the top of this post
http://greenpassivesolar.com/2010/05/movement-of-sun/http://greenpassivesolar.com/2010/05/movement-of-sun/http://greenpassivesolar.com/2010/05/movement-of-sun/http://greenpassivesolar.com/2010/05/movement-of-sun/


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Position of the Sun

The position of theSun on thecelestial sphere has many applications, includingastronomy,navigation,

surveying,meteorology,climatology,solar energy,andsundials among others. A calculation of a

complete position for any place onEarth,at any time, consists of threealgorithms:[1]

Calculate thecoordinates of theSun in theecliptic coordinate system. Convert to theequatorial coordinate system. Convert to thehorizontal coordinate system for the observer's local circumstances.

The term sun path has been assigned to notify the path of the sun which changes based on seasonal-

and-hourly alteration as the earth rotates, as well as orbits the sun. The position of the sun is one of the

main factors determining the amount of heat that can be derived from the sun. So precise information

need to be known concerning the sun path, in order to take economic decisions concerning solar energy

projects. The sun path will determine the type of materials, solar trackers and prime orientation of the

solar landscape.

Capturing Solar Energy

The most effective way to harness solar energy through solar panels, solar collectors or glass is to

installed collectors being 20 degrees perpendicular to the sun on either side. On the other hand, for

cooling system shade is important. The lowest heat is gained, the less perpendicular the sunlight is to

the building. For instance, only 35 degrees away from a perpendicular angle to the sun does significantly

reduce the amount of heat harnessed. At an elevated acute angle, the sunlight is rather reflected.

The best solar energy systems do consider the 47-degree change in the solar elevation angle that

prevails in the horizon during summer and winter. It makes a great difference in the volume of heat that

can be collected.

Earths Movements

The rotation of our planet produces approximately 23.5 degrees differences across the north and south

pool. However, the sun does equally orbit the sun in our immense solar system. The 47 degree peak of

the sunrays is caused as the earth orbits the sun. This is represented with seasonal changes that occur

from winter to summer.

Harnessing Energy in the Northern Hemisphere during the winter

In the northern hemisphere, in the winter period the sun rises in the far southeast and comes up at a

low angle just above the southern horizon. The sun does thereafter set in the southwest. In other words,the sun remains on the south part of your house (equator) throughout the day. In such conditions, a

vertical south-facing panel would be convenient to harness a maximum of thermal energy.

However, in the southern hemisphere during the winter months (June, July and August) the sun will rise

in the northeast, and will practically be perpendicular depending on the latitude of your position.
http://en.wikipedia.org/wiki/Sunhttp://en.wikipedia.org/wiki/Celestial_spherehttp://en.wikipedia.org/wiki/Astronomyhttp://en.wikipedia.org/wiki/Navigationhttp://en.wikipedia.org/wiki/Surveyinghttp://en.wikipedia.org/wiki/Meteorologyhttp://en.wikipedia.org/wiki/Climatologyhttp://en.wikipedia.org/wiki/Solar_energyhttp://en.wikipedia.org/wiki/Sundialhttp://en.wikipedia.org/wiki/Earthhttp://en.wikipedia.org/wiki/Algorithmhttp://en.wikipedia.org/wiki/Position_of_the_Sun#cite_note-0http://en.wikipedia.org/wiki/Position_of_the_Sun#cite_note-0http://en.wikipedia.org/wiki/Position_of_the_Sun#cite_note-0http://en.wikipedia.org/wiki/Coordinate_systemhttp://en.wikipedia.org/wiki/Sunhttp://en.wikipedia.org/wiki/Ecliptic_coordinate_systemhttp://en.wikipedia.org/wiki/Equatorial_coordinate_systemhttp://en.wikipedia.org/wiki/Horizontal_coordinate_systemhttp://en.wikipedia.org/wiki/Horizontal_coordinate_systemhttp://en.wikipedia.org/wiki/Equatorial_coordinate_systemhttp://en.wikipedia.org/wiki/Ecliptic_coordinate_systemhttp://en.wikipedia.org/wiki/Sunhttp://en.wikipedia.org/wiki/Coordinate_systemhttp://en.wikipedia.org/wiki/Position_of_the_Sun#cite_note-0http://en.wikipedia.org/wiki/Algorithmhttp://en.wikipedia.org/wiki/Earthhttp://en.wikipedia.org/wiki/Sundialhttp://en.wikipedia.org/wiki/Solar_energyhttp://en.wikipedia.org/wiki/Climatologyhttp://en.wikipedia.org/wiki/Meteorologyhttp://en.wikipedia.org/wiki/Surveyinghttp://en.wikipedia.org/wiki/Navigationhttp://en.wikipedia.org/wiki/Astronomyhttp://en.wikipedia.org/wiki/Celestial_spherehttp://en.wikipedia.org/wiki/Sun


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Moreover, there are some months where the sun provides more intense heat based on its position. So

solar designers have to understand the necessary solar path angles at the location where the solar

collectors are to be installed. The same applies for smart buildings, which have integrated cooling

systems.

Americas solar path analysis during different seasons of the year is available at the NOAA. However,

one thing that is general for the whole world is that the sun rises in the east and does always set in the

west.

Facts about Sunshine

The sun will be perpendicular, a straight line with no shadows, above the equator at noon (solar time)

during the 21st of March as well as the 23rd of September. Now proceeding to 23.5 degrees north of the

equator we have the Tropic of Cancer, and equally a straight line can be drawn at noon during the 21st

of June where no shadows will be seen. Now going to 23.5 degrees south of the equator we have the

Tropic of Capricorn, which on the 21st of December show no shadows, if a stick is raised straight to the

sky at noon (solar time).

unit (solar system)

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