Chapter-1 The Earth in the Solar System

Explanation:

The distinction between a planet and a star is that the former is illuminated by the light of other stars while the latter is composed of gas and has its own heat and light.

1. Some heavenly planets lack heat and light on their own. The heat and light of the stars illuminate them. Planets are the name for these objects.

2. Some asteroids are enormous and extremely hot. They have their own heat and light since they are formed of gases. Stars are the name given to these asteroids.

3. Earth, Mercury, and other planets are examples.

4. The Sun is one of the stars.

Explanation:

An area of space is our solar system. There is no vibe here. However, it has a wide variety of atmospheres on numerous worlds, including Earth. More than 150 moons are orbited by the planets in our solar system plus a few asteroids. The four massive planets all have rings, as does at least one asteroid. The solar system is composed of the Sun, the eight planets, and their satellites, as well as several asteroids and meteoroids. For instance, we may visualize the Sun as the head of the solar system's family.

Explanation:

The planets are organised according to how far they are from the Sun.there are 8 planets revolves around the sun.

These are the planets:

1. Mercury

2. Venus

3. Earth

4. Mars

5. Jupiter

6. Saturn

7. Uranus

8. Neptun

Explanation:

The three layers that make up the interior of the Earth are the crust, mantle, and core, making it distinct from other planets in the solar system. The earth's crust is its outermost layer, while its core, which lies 2900 kilometers below the surface, is its innermost layer. 

• The only planet in the solar system where conditions are suitable for sustaining life may be found in Earth.

• The temperature of the planet is just right.

• It contains air and water, both of which are crucial for human life.

As a result, the Earth is referred to be a special planet. There are elements that are favorable for maintaining life, such as air, water, and life-giving gases. Neither hot nor cold describe it.

Explanation:

We can only ever see one side of the moon at a time because of the moon's roughly 27-day orbital cycle and the identical length of time needed to complete one rotation. Whatever the reason, it only took a thousand years for the moon's spin to be altered by the gravitational pull of the Earth to the point that one rotation of the moon matched one orbit of the planet, locking one side of the moon away from the Earth forever. Tidal locking in the Earth-Moon system. Because of this, we can only see one side of the Moon.

Explanation:

The entirety of time, space, and all of their objects, such as galaxies, planets, stars, and other types of matter and energy, make up the universe. A galaxy is a vast collection of stars, gas and dust clouds, and billions of them. The accepted cosmological explanation for the universe's formation is the Big Bang theory. The universe has been expanding ever since the Big Bang, which occurred 13.787 0.020 billion years ago, according to this hypothesis. While it is uncertain how big the entire universe is in terms of space, it is feasible to calculate the size of the observable universe, which has a current diameter of around 93 billion light-years.

Explanation:

(iii) Venus

Because of how much Venus resembles Earth in terms of both size and shape, the term "Earth's Twin" has been coined. Venus is thought to be Earth's sister. The second planet from the Sun and the one nearest to Earth is Venus. Due to similarities in size and density, it is commonly referred to as Earth's twin and is one of the four inner, rocky terrestrial planets.. There are significant contrasts between these two universes; they are not mirror images of one another.

Explanation:

(ii) Earth 

The third planet from the Sun, Earth is also the fifth-largest planet in the solar system. The four seasons are brought on by the Earth's 365.25-day orbit around the Sun, which rotates on a tilted axis. The Moon is the sole natural satellite of the Earth, and the interaction between the gravity of the two results in tides by slowing the rotation of the Earth.

Explanation:

(iii) Elongated path

According to Kepler's First Law, every planet's orbit around the Sun is an ellipse.

1. One of the orbital ellipses' foci is always near the center of the Sun's orbit.

2. The planet's orbit is elongated, which means that as it revolves around its axis, its distance from the Sun fluctuates.

3. When a satellite is near perigee, it is closest to the Earth in its orbit.

4. The time during which the satellite is the furthest distance from the Earth is known as apogee.

5. Apart from Pluto and Mercury, which have more extended paths that look more eccentric, all of the planets have elongated orbits, but the eccentricities are so small that they appear round.

6. Thus, this choice is the right one.

Explanation:

Answer:

(ii) North 

The (Northern Hemisphere) North Star or Polaris are other names for the Pole Star. Since they remain fixed, pole stars are used to determine direction. This is due to the fact that it is not far from the celestial north pole, the centre around which the northern sky revolves.

Explanation:

(a) A group of stars forming various patterns is called a constellation.

EXPLANATION: Constellations are the names given to the star patterns in the sky, however, to be more precise, an asterism is a collection of stars that together make a pattern in the sky. A constellation is a collection of several stars that together make a pattern or apparent shape that, in certain mythology, represents different things, such as an animal, person, or item.

(b) A huge system of stars is called a galaxy.

EXPLAINATION: A galaxy is a collection of many stars, as well as gas, dust, and dark matter. The word "galaxy," which refers to our own galaxy, the Milky Way, is derived from the Greek word galaxia, which means milky. Galaxies are kept together by gravity in the face of the universe's overall expansion.

(c) Moon is the closest celestial body to Earth.

EXPLAINATION: The celestial body closest to our planet is the moon. Venus and Mars are the planets closest to Earth, along with the Moon. All of these heavenly entities are perpetually tethered to the solar by the force of gravity; they are perpetually compelled to revolve in elliptical orbits around the sun.

(d) Earth is the third nearest planet to the Sun.

EXPLAINATION: Earth is the third planet from the Sun, located around 93 million miles away (150 million km). 3 In When the World Spins, a day has 24 hours. Earth completes one orbit of the sun in around 365 days (one year in Earth time).

(e) Planets do not have their own heat and light.

EXPLAINATION: Planets do not undergo nuclear fusion, which is the fusing of atom-sized particles to produce energy, as stars do. Stars shine because of nuclear fusion, which produces radiation (heat and light). Planets cannot generate their own light because they lack nuclear fusion. Instead, they emit light that is a star's reflection.