Explanation

Helium is the rarest, as it's present in much smaller trace amounts (around 5.2 ppm)

Oxygen: ~209,000 ppm (20.9%)

Carbon Dioxide: ~420 ppm (0.04%)

Neon: ~18 ppm (0.0018%)

Helium: ~5.2 ppm (0.00052%) 

Xenon is generally considered the rarest of the common noble gases,

Explanation

This minimum required speed is called escape velocity.

Escape velocity of Earth is about 7 miles per second (≈ 11.2 km/s).

At this speed, an object can overcome Earth’s gravitational pull.

It does not depend on the mass of the rocket.

Escape velocity is crucial for space missions and satellites.

Explanation

Acceleration due to gravity on Earth is denoted by g.

Its standard value is 32 ft/s² (or 9.8 m/s²).

It acts downward toward the center of the Earth.

Gravity affects the motion of falling objects.

The value of g slightly varies with altitude and location.

Explanation

Days and nights are always of nearly equal length at the Equator,

The imaginary line circling the Earth at 0° latitude

This event is known as the equinox.

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Explanation

Our solar system takes approximately 225 to 230 million Earth years to complete one full orbit around the center of the Milky Way galaxy,

A period known as a galactic year or cosmic year. 

Traveling at about 514,000 mph (828,000 km/h)

Given the Sun's age, it has circled the galactic center about 20 times. 

Explanation

A constellation is traditionally defined as a group of stars that appear to form a recognizable pattern or picture in the night sky when viewed from Earth.

These patterns were named by ancient cultures after mythological figures, animals, or everyday objects and used for navigation and storytelling.

Explanation

The lowest layer of Earth's atmosphere is called the troposphere.

This layer contains about 75-80% of the atmosphere's total mass and up to 99% of its water vapor. 

Explanation

Sunlight is composed of a spectrum of light 

A spectrum revealed by Isaac Newton using a prism

That includes seven colors, which are (ROYGBIV)

1. Red
2. Orange
3. Yellow
4. Green
5. Blue
6. Indigo
7. Violet

Explanation

• Minor objects with irregular shapes orbiting the Sun are called asteroids,
• It is also known as a minor planet
• They are found mainly in the asteroid belt between Mars and Jupiter.

Explanation