1.4 Earth Sun Moon Intetactions

Question 1

How long is a lunar month?

Answer 1

29.5 days

Question 2

Why is the moon visible

Answer 2

Because it reflect sunlight

Question 3

Why is a lunar moth 2.2 days longer that the moons orbital period

Answer 3

The extra time is needed to bring the moon sun and earth in alignment so the phases can start again

Question 4

What is the correlation between the moon and sun that we have eclipsed

Answer 4

The sun is about 400 times fute her distant than the Moore and the sun is about 400 times larger in diameter so the angular size of the sun and moon are almost exactly the same

Question 5

What’s a total solar eclipse?

Answer 5

The moon must be new and its when the moon directly passes in front of the sun, it can obscure light from the photosphere and produce a dark shadow in the umbra. Solar prominences are also visibly, temperature drops, we can see Corona

Question 6

What are Baileys Beads

Answer 6

Small bright spots of sunlight caused by the Suns Ray’s shining through valleys on the moon - only visible at the end or beginning of a total solar eclipse - when just one bead is visible it’s know as the diamond ring effect

Question 7

Why don’t solar eclipses occur every month?

Answer 7

Becuase the plane of the moons orbit is tilted by 5 degrees to the plane of the earths orbit around the sun, this means at most new moons the moon is either above or below the sun in the sky

Question 8

What is the umbra in a total solar eclipse

Answer 8

The total shadow, if this observer was in a place of umbra he would be looking at a total solar eclipse

Question 9

What’s the penumbra of a solar eclipse?

Answer 9

A partial shadow, the observer may not be in line with sun and moon so only sees a partial solar eclipse

Question 10

What’s a lunar eclipse?

Answer 10

Shen the earth casts a shadow on the full moon and prevents sunlight from reaching it, they don’t occur every month due to moons plane but occur more often sure to earths shadow being larger and the moon falling into this area is more possible

Question 11

How long can a total lunar eclipse last for?

Answer 11

30mins to an hour

Question 12

What happens to the moon in a total lunar eclipse

Answer 12

The moon appears red/copper as light from the sun passes through the atmosphere and around the waste of the earth and since most blue light I scatters the red light is left behind and refracted by the earths atmosphere and illuminates the moon

Question 13

What other shadow can be seen in a partial lunar eclipse

Answer 13

The curves shade of the earth

Question 14

What are the 3 types of eclipse

Answer 14

Total - when it’s completely covered/ shadowed depending on which type of eclipse

Partial- when is partially covered or shadowed

Annular - when there’s a ring left around the luminous object being covered

Question 15

Which way does the earth spin?

Answer 15

West to east

Question 16

Which direction does the sun rise and set

Answer 16

Rises in east sets in west

Question 17

What’s a sidereal day?

Answer 17

23hr 56min and is the time taken for a star to cross over the observers meridian and reach the same point the following day - 360 degree spin

Question 18

What’s a solar day?

Answer 18

24h And its how long it takes for the SUN to go through the observers meridian and be there next day

its 4 mins longer due to the earth orbiting the sun at 1 degree every four minutes meaning we need an extra 4mins to allow the sun to return to the same position in the sky

Question 19

According to a shadow stick when would solar noon be

Answer 19

When there is the smallest shadow as this is when the sun is highest in the sky

Question 20

What’s apparent solar time?

Answer 20

It’s the physical sun - but it doesn’t move across the sun in a uniform manner due to our elliptical orbit and our polar axis being tilted - making time incorrect

Question 21

What’s the mean solar time?

Answer 21

The time we set our clocks by, it’s imaginary and it’s done so we can pretend the sun is moving uniformly across the sky

Question 22

What’s the equation of time? (Equation to fix apparent solar time)

Answer 22

EOT = apparent solar time - mean solar time (GMT)

Mean solar time = apparent solar time - EOT value

Apparent solar time =mean solar time + EOT value

Question 23

How can you calculate longitude?

Answer 23

At apparent solar time on the Greenwich meridian, for every 4 minutes you are LATER of this time you are 1 degree west of Greenwich and for every 4 minutes EARLIER of that time you are 1 degree east

Question 24

Why does the sun rise and set at different times during the year?

Answer 24

Earth’s tilt on its axis, the path of the Sun across the sky varies, and therefore, the rising and setting time changesThe reason for this is that the Earth’s axis is not perpendicular to its orbit: depending on the time of the year, either the northern or the southern hemisphere is tilted towards the Sun making the rising and setting times change

Question 25

How is aurorae caused

Answer 25

By electrons from solar wind that have accelerated to high speeds in earth magnetic field, exciting atoms and molecules of oxygen and nitrogen in the upper atmosphere, as they de-excite or decelerate they emit light at certain wavelengths

Question 26

What are the northern lights other know as

Answer 26

Aurora Borealis

Question 27

What are the southern lights other known as

Answer 27

Aurora Australis

Question 28

How long is a solar eclipse

Answer 28

7mins or less