Earth-Moon-Sun Earth and Space Science

Northern Hemisphere

The half of the earth north of the equator

Waxing Gibbous

the phase during which the illuminated side of the moon is increasing, and more than half the face of the moon is illuminated as seen from Earth

Meteorological Seasons

groupings of three months based on common climate conditions; meteorological seasons start at the beginning of the months that contain solstices or equinoxes

First Quarter

the phase during which the moon has traveled one-quarter of the way around the Earth. To observers on the Earth, it appears to be half-illuminated.

Autumnal Equinox

a day all latitudes have equal day and night, marking the beginning of fall; occurs around September 23 in the Northern Hemisphere and around March 21 in the Southern Hemisphere

Spring Equinox

a day all latitudes have equal day and night, marking the beginning of the transition from winter to summer; occurs around March 21 in the Northern Hemisphere and around September 23 in the Southern Hemisphere

Spring Tide

greater tidal effects due to the sun, moon, and Earth being aligned

Lunar Eclipse

an event in which the moon's surface is obscured or darkened by Earth's shadow

Waning Gibbous

the phase during which the illuminated side of the moon is decreasing, but more than half the face of the moon is illuminated as seen from Earth

June Solstice

the day of longest daylight in the Northern Hemisphere (summer solstice) and shortest daylight of the year in the Southern Hemisphere (winter solstice); occurs around June 21

Fall (Autumn)

transition season between summer and winter that begins with equal daytime and nighttime hours (fall equinox) and ends with the shortest daylight hours (winter solstice)

Third Quarter

the phase during which the moon has traveled three-quarters of the way around the Earth. To observers on the Earth, it appears to be half-illuminated.

Lunar Cycle / Phase of the Moon

the appearance of the surface of the moon as seen on earth

Example.

Full Moon

Earth's Tilt

Earth is tilted 23.5^o, which causes Earth's seasons

Low Tide

lower water levels due to being out of line with the gravity of the moon and sun

Fall Equinox

a day all latitudes have equal day and night, marking the beginning of the transition from summer to winter; occurs around September 23 in the Northern Hemisphere and around March 21 in the Southern Hemisphere

September Equinox

a day all latitudes have equal day and night, occurring around September 23; also known as the fall or autumnal equinox in the Northern Hemisphere

Full Moon

the phase during which the moon has traveled halfway around the Earth. To observers on the Earth, it appears to be fully illuminated.

Waning Crescent

the phase during which the illuminated portion of the moon is decreasing, and less than half the moon's face is illuminated as seen from Earth

Summer Solstice

the day of longest daylight; occurs around June 21 in the Northern Hemisphere and December 22 in the Southern Hemisphere

Spring

transition season between winter and summer that begins with equal daytime and nighttime hours (spring equinox) and ends with the longest daylight hours (summer solstice)

Bulges

areas on the earth in line with the moon's gravity which have a larger amount of water

Rotate

when a planet spins about its axis

Neap Tide

lesser tidal effects due to the sun and moon pulling on the earth from different directions

New Moon

the phase during which the moon starts the cycle around the Earth. The moon is between the Sun and the Earth. To observers on the Earth, it appears to be unlit.

Astronomical Seasons

seasons beginning on the date of each solstice or equinox; astronomical summer starts on the summer solstice around June 21

Winter Solstice

the day of the shortest daylight; occurs around December 22 in the Northern Hemisphere and June 21 in the Southern Hemisphere

Daylight Saving Time

the practice of setting clocks forward one hour during the summer months

Revolve

when a planet moves about another object; Earth revolves around the Sun, and the moon revolves around Earth

Tides

rising and falling sea levels due to the sun's and moon's gravity and the rotation of the earth

Time Zones

a region of the earth which observes a uniform standard time; there are around 37 time zones, depending on daylight saving time

Example.

Nepal Standard Time

Winter

coldest season; begins with the shortest daylight hours (winter solstice) and ends with equal daytime and nighttime hours (spring equinox)

Summer

warmest season; begins with the longest daylight hours (summer solstice) and ends with equal daytime and nighttime hours (fall equinox)

Waxing Crescent

the phase during which the illuminated side of the moon is increasing, but less than half the face of the moon is illuminated as seen from Earth

High Tide

higher water levels due to the gravity of the moon and sun

Vernal Equinox

a day all latitudes have equal day and night, marking the beginning of spring; occurs around March 21 in the Northern Hemisphere and around September 23 in the Southern Hemisphere

Solar Eclipse

Term definition.

an event in which the sun's surface is obscured or darkened by the moon

December Solstice

the day of the shortest daylight of the year in the Northern Hemisphere (winter solstice) and the longest daylight of the year in the Southern Hemisphere (summer solstice); occurs around December 22

March Equinox

a day all latitudes have equal day and night occurring around March 21; known as the spring or vernal equinox in the Northern Hemisphere