# Lab module 3: earth sun relationship

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LAB MODULE 3: EARTH SUN RELATIONSHIP

Note: Debproper relate to the GETTING STARTED lab module to imbibe tips on how to set

up and maneuver through the Google Earth ( ) rudiment of this lab.

KEY TERMS

The aftercitedcited is a roll of essential language and concepts used in this lab module:

Analemma Equation of duration Solstice

Aphelion Equinox Sphericity

Axial conterminousness Insolation Subbproper sharp-end

Axial Tilt International Era Sequence Sun Angle

Circle of whole NDVI Sun-fast, Sun-slow

Coordinated Universal Duration (UTC) Perihelion Duration zones

Daybproper sparing duration Revolution

Declination of Sun Rotation

LAB MODULE LEARNING OBJECTIVES

After successfully completing this lab module, you should be potent to:

● Compute discords in duration betwixt two colony

● Recognize and teach how duration zones work

● Differentiate the exchanges in the divergence of whole aggravate the sequence of a

year

● Identify and narrate the concludes for the spans

● Infer vegetation as an indicator for spanality

● Decipher and represent an analemma

● Calculate the Sun’s devexity for a dedicated colony and era

● Compute the equation of duration for a dedicated colony

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INTRODUCTION

This lab module discusss essential Earth-Sun connections. Topics comprise duration

zones, the equation of duration, analemma, devexity, solstice and equinox, the

reasons for spans, and the spanal absenteeism of the subbproper sharp-end. Opportunity these

topics may appear ill-assorted, you allure imbibe how they are inherently allied.

The modules set-on-foot aftercited a opportunity immodest opportunity topics, or vignettes, establish in the

accompanying Google Earth rasp. These vignettes present basic concepts allied to

Earth-Sun connections. Some of the vignettes enjoy alertnesss, videos, or short

articles that allure furnish another perspective or visual excomcolcolonization for the topic at

hand. Aftercited lection each vignette and associated links, solution the aftercitedcited

questions. Debproper silence that some rudiments of this lab may catch a opportunity to

Expand EARTH-SUN RELATIONSHIPS, and then diffuse the INTRODUCTION

folder. Double click Topic 1: Earth-Sun Relations.

Question 1: Looking at the maps, which of the aftercitedcited best showcases the

uneven weigh of insolation – and producting spanality - on planet Earth?

A. Most of the northern hemiorder is uncounted of ice and snow year round

B. Most of the northern hemiorder is mellow in ice and snow year round

C. Most of the northern hemiorder shows ice and snow advancing in the

July

D. Most of the northern hemiorder shows ice and snow minor in July

Read Topic 2: Conclude for Seasons. (Note: If you are having issues observeing

automatically careshort via the webpage)

Question 2: Why does each hemiorder entertain the identical whole of activity

from the Sun on the March and September equinoxes?

E. The subbproper sharp-end is aligned aftercited a opportunity the Tropic of Cancer

F. The subbproper sharp-end is aligned aftercited a opportunity the Tropic of Capricorn

G. The subbproper sharp-end is aligned aftercited a opportunity the Equator

H. The subbproper sharp-end is aligned aftercited a opportunity the North Pole

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Question 3: What was the deep conclude for instituting trutination duration (time

zones)?

A. To end indistinctness in communities using their own bproper duration

B. To succor astrologers foretaste courtly augmentation patterns

C. To reaffirm England’s universe dominance

D. To valiera the Culmination Conference of 1884

Question 4: Name 3 concludes aged cultures used stone structures or

modified consistent formations in-reference-to Earth-Sun or Earth-Moon connections.

A. To chart spans, cause calendars, and laud birthdays

B. To warner eclipses, trace deaths, desilence holidays

C. To chart spans, warner eclipses and cause calendars

D. To laud birthdays, trace deaths and desilence the end of days

Collapse and unreinculcate the INTRODUCTION folder.

GLOBAL PERSPECTIVE

I. Coordinated Universal Duration (UTC)

The Earth is differentd into 24 duration zones, one for each hour of the day. Earth’s 24

duration zones are closely 15° distant – a width conducive from the estimate of

degrees in a order differentd by the estimate of hours in a day (360°/24hr =

15°/hour). Noon (12pm) appears roughly when the Sun is at its prominent sharp-end in the

sky each day. For stance, noon in New York is three hours anteriorly noon in Los

Angeles owing there is (approximately) a three hour discord in when the Sun

is at its culmination.

Expand the GLOBAL PERSPECTIVE folder and then diffuse and prime the

Universal Duration Coordinated folder.

Time zones are as abundant a Sun-Earth connection as they are a civilized construct

used to trutinationize duration. The Prime Culmination - which signifies 0 rates edge

and passes through Greenwich, England - is the set-on-footing relateence sequence for duration

zonation. Duration zones are referring-to to Greenwich Balance Duration (GMT) or further

appropriately, the Coordinated Universal Duration (UTC). Examples are New York City,

USA in the evening at UTC -5 (or 5 hours flourishing UTC), or Manila, Philippines at

UTC+8 (or 8 hours onwards of UTC). In other language, when it is 8am in New York, it is

9pm in Manila.

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As you can see in Google Earth, duration zones do not frequently flourish proper sequences from

pole to pole owing of collective, economic, or geographic concludes. Duration zone

anomalies comprise the aftercitedcited:

Time Zone Irregularity Example

Time zone extends far senior or shorter

than 15 rates.

China is one duration zone.

Time zones shifts significantly eastward

or westward.

Iceland shifts 2 duration zones to be UTC 0.

Time zone does not flourish the 1-hour

system. Instead, a quietricted duration-zone unit

is used.

(summer 2:30 UTC), opportunity Nepal is 5:45

UTC

Double-click São Paulo, Brazil. You government enjoy to pan northward to ascertain the

duration zone mark close the Equator.

Question 5: In what UTC duration zone is this city located?

A. UTC -2

B. UTC -3

C. UTC +2

D. UTC+3

Question 6: If UTC 0 duration is 1pm, what is the trutination duration for this city?

A. 10 AM

B. 11 AM

C. 3 PM

D. 4 PM

Double-click Cape Town, RSA. You government enjoy to pan northward to ascertain the

duration zone mark close the Equator.

Question 7: In what UTC duration zone is this city located?

A. UTC -1

B. UTC -2

C. UTC +1

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D. UTC+2

Question 8: If UTC 0 duration is 1pm, what is the trutination duration for this city?

A. 11 AM

B. 12 PM (NOON)

C. 2 PM

D. 3 PM

Double-click Kuala Lumpur, Malaysia. You government enjoy to pan northward to

ascertain the duration zone mark close the Equator.

Question 9: Which of the aftercitedcited best narrates the duration zone irregularity

affecting this city and province?

A. Duration zone extends far senior or shorter than 15 rates

B. Duration zone shifts significantly eastward or westward

C. Duration zone does not flourish the trutination 1 hour system

D. There is no duration zone for the dedicated colony

Question 10: What is the original conclude for this duration zone irregularity?

A. Collective boundaries of Malaysia

B. Economic commerce for Southeast Asia

C. Railway schedules

D. International law

Question 11: In what UTC duration zone is this city located?

A. UTC-7

B. UTC-8

C. UTC +7

D. UTC +8

Question 12: If UTC 0 duration is 1pm, what is the trutination duration for this city?

A. 8 PM

B. 9 PM

C. 5 AM

D. 6 AM

Double-click, and prime, Pitcairn Islands

Question 13: Which of the aftercitedcited best narrates the duration zone irregularity

affecting these islands?

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A. Duration zone extends far senior or shorter than 15 rates

B. Duration zone shifts significantly eastward or westward

C. Duration zone does not flourish the trutination 1 hour system

D. There is no duration zone for the dedicated colony

Question 14: What is the original conclude for this duration zone irregularity?

A. Geographic colony of the islands

B. Economic commerce for the islands

C. International law

D. Strict ideal code

Question 15: In what UTC duration zone are these islands located?

A. UTC -6

B. UTC -8.5

C. UTC +6

D. UTC +8.5

Question 16: If UTC 0 duration is 1pm, what is the trutination duration for these

islands?

A. 4:30 PM

B. 9:30 PM

C. 4:30 AM

D. 9:30 AM

Collapse and unreinculcate the Universal Duration Coordinated folder.

II. Sunshine Savings

Double-click, and prime, Sunshine Sparing Time

Many regions in the universe enjoy adopted sunshine sparing duration (DST), or the

advancing of UTC duration for a dedicated colony. This is chiefly penny for North America

and Europe. As an stance, New York, New York agitates from Eastern Standard

Time (EST) to Eastern Sunshine Duration (EDT) betwixt the months of March and

November. The trutination duration during sunshine sparing duration is adjusted from UTC -5

(EST) to UTC -4 (EDT).

Question 17: If it is 12 PM (noon) in Manila, Philippines (UTC +8), what is

the duration during EDT in New York (UTC -4)?

A. 12 AM

B. 4 PM

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C. 8 PM

D. 8 AM

III. International Era Line

Double-click the International Era Sequence folder and then reinculcate the IDL folder.

The International Era Sequence (IDL) is an unreal sequence that runs from pole to pole on

further or short the 180°E/W longitude. Notpotent adversative to this appear from 50°N to

75°N and from the Equator to 50°S.

If you morose the IDL traveling westwardly (from east to west), you need to add a

day to your duration. In other language, a Thursday becomes a Friday. If you morose the

IDL traveling eastwardly (from west to east), you would deduct a day. For

example, a Friday becomes a Thursday. To opine of it another way, the Earth

“starts” the day (12:01 am) on the west margin of the IDL, and catchs a liberal 24 hours

for 12:01 am to arrive-at the east margin of the IDL.

Double-click and prime IDL North.

Question 18: Why does the IDL diverge from 180° E/W in this colony?

A. To recital for the firmer orderal despatch internal the North Pole

B. The IDL is aftercitedcited the 180° E/W culmination – there is no solution in this

location

C. To flourish the bathymetry of the sea in this colony

D. To enjoy the islands of Alaska in the identical duration zone as the quiet of Alaska

Double-click and prime IDL South.

Question 19: Why does the IDL diverge from 180° E/W in this colony?

A. To recital for the firmer orderal despatch internal the Equator

B. To flourish the bathymetry of the sea in this colony

C. To enjoy the islands of Kiribati in the identical duration zone.

D. To different the islands countries on the west margin of the IDL from the

island countries located east of 180° E/W

Collapse and unreinculcate the GLOBAL PERSPECTIVE folder.

REASONS FOR SEASONS

There are five unapprove concludes for the spans – tilt (at 23.5 rates), form

(about the Sun), order (consummate 24 hours), axial conterminousness (unroving alignment

during form about Sun), and protuberance (the Earth’s form). These five

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reasons recital for the immodest divisions of the year - flow, summer, autumn (fall),

and evening – regularly traceed by unapprove clime patterns, temperatures

fluctuations, vegetation chilless and so on. The rate of these spanal exchange

becomes further clear as you agitate far from the Equator (as spanality in

tropical regions is minimal).

In this exception, we allure discuss three of the five concludes for the spans – axial tilt,

revolution, and order.

I. Axial Tilt

Because of the tilt of the Earth, the whole of activity Earth entertains from the Sun

is subject on colony and duration of year. On the equinoxes (March 20 and

September 22 or 23), the Sun is at-once aggravatehead (the sub-bproper sharp-end) and all

areas on Earth entertain the identical 12 hours of bproper activity (sunlight). On the

solstices (June 20 or 21 and December 21 or 22), the subbproper sharp-end is on the tropic

of cancer (23.5 rates North) or the tropic of capricorn (23.5 rates South),

resulting in the most inadequate classification of bproper activity on Earth.

Expand and prime the REASONS FOR SEASONS folder. Double-click

Overexamination and then decipher the quotation and observe the alertness.

Question 20: What is the connection betwixt the spans and the composition

of the sub-bproper sharp-end?

A. The sub-bproper sharp-end is furthest north during the flow equinox

B. The sub-bproper sharp-end is furthest north during the autumn equinox

C. The sub-bproper sharp-end is furthest north in summer (June) solstice

D. The sub-bproper sharp-end is furthest north in evening (December) solstice

Question 21: Explain how Earth’s spans would be if the Earth did not tilt

on its axis.

A. Annually, there would be further than immodest spans

B. Annually, there would be no further spans

C. Annually, there would be one dry span and one wet span

D. Annually, there would one “hot” span on Earth

II. Revolution

It catchs 365.24 days for the Earth to consummate one form about the Sun. And

although the Earth’s circuit is allusive , the alteration in interval betwixt the Earth’s

circuit closeest to the Sum (perihelion) or ultimate from the Sun (alphelion) is not

great sufficient to recital for the spans.

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Question 22: Assume the Earth was tilted and workd, but did not revolve

about the Sun. How would this wave the colony of sub-bproper sharp-end aggravate

a dedicated year?

A. The sub-bproper sharp-end would not agitate

B. The sub-bproper sharp-end would agitate daily instead of annually

C. The sub-bproper sharp-end would agitate betwixt the tropics sound approve it does

today

D. There would be no sub-bproper sharp-end

III. Rotation

Earth consummates one order closely consummate 24 hours. This order is what

gives us days and nights.

Double-click Divergence of Illumination. This appearance shows the divergence of whole,

or the day-night sequence, for June 21.

At 9:00pm EST in New York, South America is in gloom, opportunity North America is

still in day bright. If we firm progressive 2 hours to 11pm EDT in New York, the divergence of

whole has agitated westward. Indeed, the Earth’s order succors fix the

Sun’s activity is spdecipher aggravate the Earth’s deportment.

Question 23: Assume the Earth was tilted and revolved, but did not work.

What would the spans be approve if the Earth did not work?

A. No exexchange to the unconcealed spans/seasonality on Earth

B. There would be one span on Earth

C. There would a invariable summer-type span on one margin of Earth and a

invariable evening-type span on the other margin of Earth.

D. Earth would test a summer-type span (aftercited a opportunity sunlight) for about 6

months and a evening-type span (aftercited a opportunity no bright) for about 6 months

Click Back to Google Earth, which is located in the top-left retreat in the

We are now going to go through one order on Earth.

Zoom out as far as you can until the Earth is as slender as Google Earth allows.

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Click Show sunbproper acrosss the hope ( ). A duration description displays at

the top of the slide bar. (Note: Verify that the Historical Imagery is off

owing it can disguise the Show sunbproper acrosss the hope slide bar).

Using your mouse, attribute the cursor on the Earth and agitate it about until the

Sun is flourishing the Earth. Then, set North in the defect comcomcolcolonization (inculcate N).

Question 24: How does the divergence of whole seem to the party of the

Earth unconcealedly oppositeness you?

A. The party of the sphere oppositeness me is illuminated

B. The party of the sphere oppositeness me is not illuminated (shadowed)

C. The western party of the sphere oppositeness me is illuminated

D. The eastern party of the sphere oppositeness me is illuminated

Move the slide bar inactively aggravate the proximate 24 hours.

Question 25: What is the line of Earth’s divergence of whole?

A. Predominately westward (proper to left)

B. Predominately eastward (left to proper)

C. Predominately northward (floor to top)

D. Predominately southward (top to floor)

Turn off Show sunbproper acrosss the hope ( ).

Collapse and unreinculcate the REASON FOR SEASONS folder.

NDVI

Expand the NDVI folder.

This folder contains a order of images showing Normalized Discord Vegetation

Index (NDVI) for the year 2011. NDVI is a referring-toly unaffected way of discareshort where

vegetation is most chill, which resources that the vegetation is animated and producing

greenness from its leaves and other insert talents. In unconcealed, the blacker the chill is

for a dedicated area, the further vegetation caggravate and/or augmentation exists for that area.

In this exception you allure be seeming at three colonys – Africa, North America, and

Southeast Asia. To set-on-foot, let’s go to North America in January.

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Double-click North America.

Remember that in the Northern hemisphere, the Sun is inferior in the sky in January,

and thereby entertains short plain sunbproper (bproper activity). As a product, the chill

appears absent at eminent edges.

Systematically click through the months (January through December) and silence

the chill areas in North America. (Note: The images government catch some duration to

load; as a sketch, cycle through the months partially rather than repressing all of

them at one duration).

Question 26: Which of the aftercitedciteds months is the seniority of North

America black chill?

A. January

B. April

C. July

D. October

Question 27: How does this month (you primeed in Topic 25)

fit to the sub-bproper sharp-end of the Sun?

A. The sub-bproper sharp-end close the equator

B. The sub-bproper sharp-end close its most northern composition

C. The sub-bproper sharp-end close its most southern composition

D. The comcomcolcolonization of the sub-bproper sharp-end does not matter

Double-click and prime Africa.

Systematically click through the NDVI months (January through December) and

silence the chill areas in Africa.

Question 28: In which of the aftercitedcited month is the extensive chill

(vegetation) area arrive-at furthest South?

E. January

F. April

G. July

H. October

Question 29: How does the northernmost sharp-end fit to the sub-solar

sharp-end of the Sun?

A. The sub-bproper sharp-end is aggravate the equator

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B. The sub-bproper sharp-end is at its most northern composition

C. The sub-bproper sharp-end is at its most southern composition

D. The comcomcolcolonization of the sub-bproper sharp-end does not matter

Double-click and prime Borneo.

This is the island of Borneo (center) and the embracing islands that arrive-at up the

Philippines (to the north) and Indonesia (to the south) in Southeast Asia. The island

Systematically click through the NDVI months (January through December) and

silence the chill areas in Borneo.

Question 30: What is the aggravateall incline in NDVI for the year?

A. The NDVI is unlikeively inferior in March

B. The NDVI is unlikeively eminent in September

C. The NDVI varies insignificant aggravate the unimpaired year

D. The NDVI is unlikeively inferior in December

Question 31: Aftercited a opportunity reference to Sun prepossession, why do we see such an NDVI incline

for the island of Borneo? (Choose the one that is loose)

A. There is insignificant alteration in Sun prepossession owing Borneo is at the equator

B. Borneo basically entertains the identical whole of bproper radiation year round

C. Borneo entertains raindeccourse throughout the year

D. Few, if any clouds, conceal the Sun from Borneo year round

Collapse and unreinculcate the NDVI folder.

ANALEMMA

An analemma is a chart that you use to course the Sun’s devexity and to

individualize the equation of duration. The Sun’s devexity is the edge of the Sun’s

bproper sharp-end for a dedicated era. The Sun’s bproper sharp-end is the where the Sun is at-once

over (90°) at balance bproper duration.

The Earth’s circuit is allusive and, as a product, revolves about the Sun at varying

speeds depending on the duration of year. In June and July, the Earth revolves inactiveer,

compared to December and January. Hence, as the despatch of form varies, we

need the equation of duration to individualize the discord betwixt observed bproper duration

(the duration when the Sun is at its prominent sharp-end in the sky for your colony) and

actual duration:

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● If the Sun is at its prominent sharp-end anteriorly noon (12:00pm), then the duration is

said to be Sun-fast.

● If the Sun is at its prominent sharp-end aftercited 12:00pm, duration is said to be Sun-slow.

An analemma allure number us how firm (or inactive) the Sun is referring-to to noon.

Expand the Analemma folder and then click Introduction to examination the

I. Sun Angle

Expand Sun Angle.

Assume we are in Atlanta, Georgia, USA (33.95°N, 83.32°W). This city is in the

Northern hemisphere. It as-well implements sunshine sparing duration, so “noon” is

technically at 1pm. Using the stance in the alertness, we can decipher the graph to

individualize the Sun’s devexity on August 1 is 18°N. In other language, the Sun is

at-once aggravatehead (Sun’s bproper sharp-end) at 18°N. However, we are not located at 18°N

but farther north at ~34°N. This resources that the Sun is not at-once aggravatehead but at

an prepossession, unreserved as-well as an improvement prepossession or bproper improvement prepossession. So what is the

Sun’s improvement prepossession at its prominent sharp-end in Atlanta, Georgia (~34°N) on August 1?

To solution this topic we can use the aftercitedcited equation:

Altitude Prepossession = 90° - edge ± devexity

When our colony and the Sun’s devexity are in the identical hemiorder (North or

South), we add the devexity treasure in the equation. When they are in opposite

hemispheres, we deduct the devexity treasure. In our stance then, we are in the

identical hemisphere, so we add. We understand our edge is 34 rates and the

devexity is 18 rates, so solution is:

Altitude Prepossession = 90° - 34° +18° = 74°

Altitude Prepossession = 74°

So, on August 1 in Atlanta, Georgia, the Sun prepossession at its prominent sharp-end would be

74°.

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Suppose we were in Cape Town, South Africa (33.92°S, 18.45°E) on August 1.

Rounding the edge to 34°S, what is the Sun prepossession at noon?

Altitude Prepossession = 90° - 34° - 18°

Altitude Prepossession = 38°

As we can see, the Sun’s improvement prepossession on August 1 at noon is abundant inferior in Cape

Town, South Africa than in Atlanta, USA.

Using this equation, solution the aftercitedcited topics.

Double-click and prime Colony A.

Question 32: What is the edge (degrees merely) for Colony A?

A. 0°E

B. 0°S

C. 78°W

D. 78°N

Question 33: What is the Sun’s improvement prepossession for Colony A on September

21?

Altitude Prepossession = 90° - edge ± devexity =

A. 90° - 0 – 0 = 90°

B. 90° - 90 + 0 = 0°

C. 90 – 78 – 0 = 12°

D. 90 +78 – 0 = 168°

Double-click and prime Colony B.

Question 34: What is the edge (degrees merely) for Colony B?

A. 68°E

B. 68°N

C. 133°W

D. 113°N

Question 35: What is the Sun’s improvement prepossession for Colony B on December

21?

Sun Improvement Prepossession = 90° - edge ± devexity =

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A. 90° - 68 – 22 = 0°

B. 90° - 68 + 22 = 44°

C. 133 - 90 - 22 = 21°

D. 113 - 90 -22 = 41°

II. Equation of Time

In union to determining the Sun’s improvement prepossession of a dedicated edge, we can use

the analemma to individualize the duration at which the Sun is at-once aggravatehead for a

dedicated era.

Click Equation of Duration and examination the alertness.

On May 1, the equation of duration is 3 minutes Sun–fast, balanceing the Sun arrive-ates its

prominent sharp-end 3 minutes anteriorly noon (11:57 AM).

Question 36: Is the equation of duration Sun-firm or Sun-inactive on the March

equinox? By how divers minutes?

A. Sun-firm by 4 minutes

B. Sun-firm by 12 minutes

C. Sun-inactive by 8 minutes

D. Sun-inactive by 0 minutes

Question 37: What duration does the Sun arrive-at its prominent sharp-end on November

25?

A. 12:00 + 16 minutes = 12:16 PM

B. 12:00 - 13 minutes = 11:47 AM

C. 12:00 - 16 minutes = 11:44 PM

D. 12:00 + 13 minutes = 12:13 PM

Question 38: What duration does the Sun arrive-at its prominent sharp-end on June 15?

E. 12:00 + 0 minutes = 12:00 PM

F. 12:00 + 4 minutes = 11:56 AM

G. 12:00 - 4 minutes = 11:56 PM

H. 12:00 + 12 minutes = 12:12 PM

Collapse and unreinculcate the Analemma folder. You enjoy consummated Lab Module 3.