Which of the following describes the effect of launching a rocket from the equator?

Launching a rocket from the equator allows for an additional speed from Earth's rotation, which is a significant advantage for space missions. The Earth rotates on its axis, and at the equator, this rotational speed is about 1,670 kilometers per hour (approximately 1,040 miles per hour). When a rocket is launched from this location, it benefits from this rotational velocity, effectively providing an initial boost in speed. This added speed can help the rocket reach the required velocity to break free from Earth’s gravitational pull more efficiently, reducing the amount of fuel needed for the launch.

This advantage makes equatorial launches particularly favorable for certain types of missions, including those involving satellites that need to achieve geostationary orbits. The efficiency gained through this method can lead to lower costs and potentially more successful launches.

In contrast, launching from locations further away from the equator does not provide this same benefit, as those locations experience a lower rotational velocity of the Earth. Hence, the option highlighting the additional speed from Earth's rotation correctly identifies the key effect of launching a rocket from the equator.