SCIENCE

Question 1

Nebula

Answer 1

a cloud of gas and dust in outer space, visible in the night sky either as an indistinct bright patch or as a dark silhouette against other luminous matter.

Question 2

Solar Nebula

Answer 2

Solar Nebula. Our solar system began forming within a concentration of interstellar dust and hydrogen gas called a molecular cloud. The cloud contracted under its own gravity and our proto-Sun formed in the hot dense center. The remainder of the cloud formed a swirling disk called of the solar nebula.

Question 3

Nuclear Fusion

Answer 3

a nuclear reaction in which atomic nuclei of low atomic number fuse to form a heavier nucleus with the release of energy.

Question 4

Sunspot

Answer 4

Sunspots are temporary phenomena on the Sun’s photosphere that appear as spots darker than the surrounding areas. They are regions of reduced surface temperature caused by concentrations of magnetic field flux that inhibit convection. Sunspots usually appear in pairs of opposite magnetic polarity.

Question 5

Terrestrial Planets

Answer 5

A terrestrial planet, telluric planet, or rocky planet is a planet that is composed primarily of silicate rocks or metals. Within the Solar System, the terrestrial planets are the inner planets closest to the Sun, i.e. Mercury, Venus, Earth, and Mars.

Question 6

Prograde Rotation

Answer 6

prograde. [prō′grād′] Having a rotational or orbital movement that is the same as most bodies within a celestial system. In our solar system, prograde movement for both rotating and orbiting bodies is in a counterclockwise direction when viewed from a vantage point above the Earth’s north pole. Compare retrograde.

Question 7

Retrograde Rotation

Answer 7

All eight planets in the Solar System orbit the Sun in the direction of the Sun’s rotation, which is counterclockwise when viewed from above the Sun’s north pole. Six of the planets also rotate about their axis in this same direction. The exceptions – the planets with retrograde rotation – are Venus and Uranus.

Question 8

Gas Giant

Answer 8

a large planet of relatively low density consisting predominantly of hydrogen and helium, such as Jupiter, Saturn, Uranus, or Neptune.

Question 9

Satellite

Answer 9

In the context of spaceflight, a satellite is an artificial object which has been intentionally placed into orbit. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as Earth’s Moon.

Question 10

New Moon

Answer 10

In astronomy, the new moon is the first lunar phase, when the Moon and Sun have the same ecliptic longitude. At this phase, the lunar disk is not visible to the unaided eye, except when silhouetted during a solar eclipse. Daylight outshines the earthlight that dimly illuminates the dark side of the new Moon.

Question 11

Waxing Crescent

Answer 11

The moon is less than one-half illuminated by the sun but less than one quarter illuminated. Occurs when the moon’s illumination is increasing, First Quarter. The moon is one-half illuminated by the sun.

Question 12

1st Quarter Moon

Answer 12

The First Quarter Moon / Half Moon. The First Quarter Moon is a primary Moon phase when we can see exactly half of the Moon’s surface illuminated. If it is the left or right half, depends on where you are on Earth. This First Quarter Moon is in the Northern Hemisphere and mirrors approximately the calendar symbol.

Question 13

Waxing Gibbous

Answer 13

Waxing means that it is getting bigger. Gibbous refers to the shape, which is less than the full circle of a Full Moon, but larger than the semicircle shape of the Moon at Third Quarter. With some exceptions, the Waxing Gibbous Moon rises during the day, after noon.

Question 14

Full Moon

Answer 14

the phase of the moon in which its whole disk is illuminated.

Question 15

Waning Gibbous

Answer 15

The waning (shrinking) gibbous Moon rises after sunset, transits the meridian after midnight and sets after sunrise. The waning gibbous phase repeats every 29.531 days – one synodic month. The Moon’s motion around the Earth, with the Sun illuminating only one side of the Earth and Moon.

Question 16

Last Quarter Moon

Answer 16

Last quarter: The moon has moved another quarter of the way around Earth, to the third quarter position. The sun’s light is now shining on the other half of the visible face of the moon. Waning crescent: Less than half of the moon’s face appears to be getting sunlight, and the amount is decreasing.

Question 17

Waning Crescent

Answer 17

Third Quarter. The moon is one-half illuminated by the sun. Occurs when the moon’s illumination is decreasing, Waning Crescent. The moon is less than one-half illuminated by the sun but less than one quarter illuminated.

Question 18

Solar Eclipse

Answer 18

A solar eclipse occurs when an observer passes through the shadow cast by the Moon which fully or partially blocks the Sun. This can only happen when the Sun, Moon and Earth are nearly aligned on a straight line in three dimensions during a new moon when the Moon is close to the ecliptic plane.

Question 19

Lunar Eclipse

Answer 19

A lunar eclipse occurs when the Moon passes directly behind Earth and into its shadow. This can occur only when the Sun, Earth, and Moon are exactly or very closely aligned, with Earth between the other two. A lunar eclipse can occur only on the night of a full moon.

Question 20

Comet

Answer 20

a celestial object consisting of a nucleus of ice and dust and, when near the sun, a “tail” of gas and dust particles pointing away from the sun.

Question 21

Asteroid

Answer 21

Asteroids are minor planets, especially of the inner Solar System. Larger asteroids have also been called planetoids.

Question 22

Asteroid Belt

Answer 22

The asteroid belt is the circumstellar disc in the Solar System located roughly between the orbits of the planets Mars and Jupiter. It is occupied by numerous irregularly shaped bodies called asteroids or minor planets.

Question 23

Meteoroid

Answer 23

a small body moving in the solar system that would become a meteor if it entered the earth’s atmosphere.

Question 24

Meteorite

Answer 24

a meteor that survives its passage through the earth’s atmosphere such that part of it strikes the ground. More than 90 percent of meteorites are of rock, while the remainder consist wholly or partly of iron and nickel.

Question 25

Meteor

Answer 25

a small body of matter from outer space that enters the earth’s atmosphere, becoming incandescent as a result of friction and appearing as a streak of light.