Grade 3 Objective Testing - Outer Space

The main color of Earth is blue because 3/4 of the Earth is covered by water.

When visiting the moon, people need to wear special suits to protect themselves from the harsh environment, including extreme temperatures, lack of atmosphere, and radiation. These suits provide them with oxygen, regulate temperature, and protect them from the vacuum of space. Extra money, shoes, umbrellas, plants, and animals are not necessary for visiting the moon.

The moon has NO air and water.

The Earth rotates on its axis every 24 hours, causing different parts of the Earth to face towards or away from the Sun at different times. During the day, the part of the Earth facing the Sun receives sunlight, making it bright. However, during the night, that part of the Earth is facing away from the Sun, resulting in darkness. Therefore, even though the Sun is always glowing, the night here on Earth is dark due to the rotation of the Earth.

The correct answer explains that the Earth remains warm because the Sun is close to it and the burning gases from the Sun are extremely hot. This suggests that the Sun's proximity to the Earth allows it to emit heat and radiation, which in turn warms the Earth's surface and atmosphere.

From the given passage, it is mentioned that Earth looks like a "blue ball" from outer space.

The correct answer is that there are holes all over the moon's surface and they are called craters. Craters are formed when meteoroids or asteroids collide with the moon's surface, causing an impact that creates a depression or hole. These craters can range in size from small to large and can be found all over the moon's surface.

The correct answer is that scientists believe meteorites smashed into the Moon millions of years ago and formed the craters. This explanation is based on scientific evidence and research. Meteorite impacts are known to have occurred on the Moon's surface, and the craters are a result of these impacts. The presence of craters on the Moon's surface is widely accepted in the scientific community and is supported by various studies and observations.

Scientists are still studying moon rocks that were brought back from the original first visit to the moon. This suggests that the statement is true. The fact that scientists are still studying these rocks indicates that there is ongoing research and analysis being conducted on the samples collected during the first moon landing. This research could provide valuable insights into the moon's composition, geological history, and potentially even the origins of the solar system.

Continents are massive land masses that are surrounded by water, giving them the appearance of small islands when viewed from space or a distance. They are much larger than islands and are home to a variety of ecosystems, diverse cultures, and numerous countries.

The Sun is the closest star to Earth. This is because the Sun is located at the center of our solar system and all the planets, including Earth, orbit around it. While there are billions of stars in the universe, the Sun is the closest one to us, providing us with heat, light, and energy.

The correct answer is a sphere. This is because Earth is not perfectly round, but it is an oblate spheroid, meaning it is slightly flattened at the poles and bulging at the equator. This shape is a result of Earth's rotation, which causes the equator to experience centrifugal force, pushing material away from the center and causing the bulge. Overall, Earth's shape is closest to that of a sphere.

The statement is true because the Sun's burning gases emit a tremendous amount of heat and energy. Despite being 93 million miles away from the Earth, the heat from the Sun reaches our planet and warms it. This is due to the process of radiation, where the Sun's energy is transmitted through space in the form of electromagnetic waves. These waves include heat and light, which are absorbed by the Earth's atmosphere and surface, causing the planet to warm up.

It is false because the "Sun" is the closest star to Earth.

The Sun appears very big because of its proximity to Earth and its status as the closest star. Being relatively close to our planet makes it appear larger in our perspective compared to other stars. Additionally, the Sun's size itself contributes to its apparent largeness, as it is bigger than any other star.

Walking around the entire Earth would take more than a year. The Earth's circumference is about 24,901 miles (40,075 kilometers). Assuming someone walks 20 miles per day without breaks, it would still take over 1,245 days—well over three years. Factoring in terrain, rest, and real-life challenges, it would definitely take more than a year to walk around the whole planet.

Astronauts first landed on the moon in 1969. This was a significant milestone in human history and was achieved during the Apollo 11 mission. The landing was a culmination of years of research, development, and testing by NASA. The mission was led by astronauts Neil Armstrong, Buzz Aldrin, and Michael Collins. Armstrong famously took the first step onto the lunar surface and proclaimed, "That's one small step for man, one giant leap for mankind." The moon landing marked a major achievement in space exploration and opened up new possibilities for future missions.

The correct answer is 25,000 miles because this is the approximate circumference of the Earth. The Earth is a sphere, and the distance around a sphere is calculated using the formula 2πr, where r is the radius of the sphere. The radius of the Earth is approximately 3,963 miles, so the circumference is approximately 2π(3,963) = 24,901 miles. Rounded to the nearest thousand, this is 25,000 miles.

Astronauts traveled another 6 more years to the moon after the initial visit in 1969.

The correct answer is 3/4, three-fourths, most of the earth's surface, more than half. This is because approximately 71% of the earth's surface is covered by water, which is equivalent to three-fourths or more than half of the total surface area. This large amount of water gives the earth's surface a predominantly blue appearance.

Astronauts in outer space see white clouds wrap around the Earth like a light blanket because clouds appear white from space due to the reflection of sunlight off their water droplets or ice crystals. This phenomenon creates a beautiful and serene view of the Earth's atmosphere from above.

The moon has no air or water. This means that there is no atmosphere or liquid water on the moon's surface. The lack of air means that there is no oxygen for living organisms to breathe, and the lack of water means that there is no liquid for life to exist or for weather patterns to occur. The moon's surface is dry and airless, making it inhospitable for life as we know it.

Scientists believe that meteorites, which are small celestial objects that enter the Earth's atmosphere, smashed into the Moon millions of years ago. These impacts created craters on the Moon's surface.

The correct answer is "plants, animals". This means that humans without suits cannot live on the moon without the presence of plants and animals. The presence of plants is essential for providing oxygen through photosynthesis, while animals play a crucial role in maintaining the ecosystem and food chain. Therefore, without these two components, sustaining human life on the moon would be impossible.