Space physics Flashcards
Order of solar system
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
How does the earth rotate around the sun?
The Earth is a planet that rotates from west to east on its axis, which is tilted, once in approximately 24 hours at an angle of approximately 23.5°
How does the way the earth rotates around the sun affect daily apparent motion of the sun?
Because of this rotation (counterclockwise from west to east), an observer on Earth sees the Sun appear to rise in the east, move across the sky, and set in the west. This is known as the apparent daily motion of the Sun
What happens during equinoxes?
- day and night are approximately equal in length
- the Sun appears to rise exactly in the east and set exactly in the west
What is the cycle of day and night caused by?
- Day and night are caused by the Earth’s rotation on its axis
- One full rotation takes approximately 24 hours, which means the half of the Earth’s surface facing the Sun experiences day and the other half of the Earth’s surface, facing away from the Sun, experiences night
How long does it take the Earth to orbit the Sun?
the Earth orbits the Sun once in approximately 365 days
What does the earth axis of rotation mean for hemispheres?
one hemisphere tilts towards the Sun and receives more solar radiation while the other hemisphere tilts away from the Sun and receives less solar radiation (six months later, the hemispheres tilt in the opposite direction)
What happens when it’s summer in the northern hemisphere?
When it is summer in the northern hemisphere the northern hemisphere is tilted towards the Sun meaning it receives a greater proportion of solar radiation
the southern hemisphere experiences winter because it is tilted away from the sun receiving a smaller proportion of solar radiation
It is opposite for winter in northern hemisphere/summer in southern hemisphere
What happens during spring and autumn in terms of solar radiation?
When it is spring or autumn, both hemispheres receive about the same amount of solar radiation
What happens during 20th March?
Spring equinox in NH
Autumn equinox in SH
means equal hours of day and night
What happens during March, April, May?
NH: spring (days are longer than nights hours of daylight increase)
SH: autumn (days are shorter than nights hours of daylight decrease)
What is on 21st June?
NH: summer solstice (longest hours of daylight)
SH: winter solstice (shortest hours of daylight)
What happens during June, July, August?
NH: summer (days are longer than nights, hours of daylight decrease)
SH: winter (days are shorter than nights, hours of daylight increase)
What is on 23rd September?
NH: autumn equinox (equal hours of day and night)
SH: spring equinox (equal hours of day and night)
What happens during September, October, November?
NH: autumn (days are shorter than nights, hours of daylight decrease)
SH: spring (days are longer than nights, hours of daylight increase)
What happens on 21st December?
NH: winter solstice (shortest hours of daylight)
SH: summer solstice (longest hours of daylight)
What happens during December, January, February?
NH: winter (days are shorter than nights, hours of daylight increase)
SH: summer (days are longer than nights, hours of daylight decrease)
Properties of the moon
The Moon is a natural satellite that orbits around the Earth in a roughly circular orbit
- takes about one month (28 days) to complete one orbit
- rotates on its axis once every 28 days so the same side always faces the Earth
- It is visible in the night sky because it reflects the light from the Sun
- orbits counterclockwise
What happens on day 0 moon cycle?
On day 0, a new moon is observed, where: the Moon is positioned between the Earth and the Sun
- the side of the Moon facing away from Earth is fully illuminated
- none of the Moon’s surface is visible from Earth
days 1-6 of the moon cycle
Waxing crescent moon
(when shape is thickening, illuminated on left side)
day 7 of moon cycle
On day 7, the first quarter phase is observed
days 8-13 of moon cycle
Waxing gibbous (like 3/4 of moon is illuminated from left side)